Circular 23Z8

TDI / AEM-C Emissions Service Action
Code: 23Z8
Subject
Release Date
Affected Vehicles
3.0L TDI Engine Gen 2 PC – Emissions System Modification Correction (AEM-C)
August 14, 2019
U.S.A.: 2014-2016 MY Audi Q5, A6, A7 A8/A8L 3.0L TDI Generation 2 PC
Check Campaigns/Actions screen in Elsa on the day of repair to verify that a VIN qualifies for repair under this
action. Elsa is the only valid campaign inquiry & verification source.
AEM-C Description
IMPORTANT!
This Emissions
Service Action
(AEM-C) ONLY
applies to vehicles
that have already
received the AEM
(23V4 campaign)
Parts Information

Campaign status must show “open.”

If Elsa shows other open action(s), inform your customer so that the work can also be completed at
the same time the vehicle is in the workshop for this campaign.
Audi is releasing a software calibration update to the Approved Emissions Modification (AEM)
to improve on-board diagnostics (OBD) monitoring of vehicle emissions systems and provide
other improvements to the software used by the vehicle. Additionally, to reduce soot
accumulation affecting the oxygen sensor, it is necessary to replace and relocate the sensor,
which requires replacement of the diesel oxidation catalyst (DOC) and diesel particulate filter
(DPF).

This Emissions Service Action (AEM-C) MUST explicitly be elected by the customer
and be clearly marked on the repair order PRIOR to commencing the update.

This Emissions Service Action (AEM-C) only applies to vehicles that have received
the Approved Emissions Modification (AEM – 23V4 campaign).

Dealers MUST provide a copy of the attached customer letter to each customer who
presents their vehicle for repair under this Emissions Service Action (AEM-C).

If a vehicle has not received the AEM (23V4 campaign), this Emissions Service
Action (AEM-C) does not apply.
Parts Control Type: Allocation
Parts allocation will occur once a week for the part numbers below with planned delivery on
Wednesdays. Allocation requests for additional parts will not be accepted. If there is an issue
with the allocation quantity, please contact your Field Representative.
Initial Allocation: Yes
Dealers will be sent an initial allocation prior to customer notification. If no initial allocation was
received, please reference the Repair Projection Tool (below) to view your potential VIN
population.
Criteria
Part Number
01,02,03
01,02,03
01,02,03
4H0-254-750-HX
4H0-298-099
04L-906-262-B
Description
(per POC)
PARTICULAT
FIT. SET
OXYGEN SEN
Qty. per
Vehicle
1
1
1
Ordering
Method
Allocation
Allocation
Allocation
Repair Projection Tool (right click to open):
Code Visibility
On or about August 14, 2019, affected vehicles will be listed on the Inventory Vehicle Open
Campaign Action report under My Dealership Reports (found on www.accessaudi.com & OMD
Web). A list will not be posted for dealers who do not have any affected vehicles.
On or about August 14, 2019, this campaign code will show open on affected vehicles in Elsa.
On or about August 14, 2019, affected vehicles will be identified with this campaign code in the
VIN Lookup tool at www.audiusa.com.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 1 of 77
Owner Notification
Loaner/Rental Vehicle –
REQUIRED!
Owner notification will take place on July 30, 2019. Owner letter examples are included in this
bulletin for your reference.
Customers are eligible to receive a loaner vehicle. Please refer to Warranty Bulletin
AWA 19-05 for claiming instructions.
To remain compliant with the Settlement Agreement, Service Consultants must complete a
Loaner/Rental label and it must be signed by the customer. This documents each customer’s
decision to accept or decline the offer for a loaner or rental vehicle while the Approved
Emissions Modification - Correction was being performed on their vehicle.
Affix the completed label to the Repair Order.
Additional Information
Please alert everyone in your dealership about this action, including Sales, Service, Parts
and Accounting personnel. Contact Warranty if you have any questions.
Dealers must ensure that every affected inventory vehicle has this campaign completed before
delivery to consumers.
The information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These procedures
are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To determine whether
this information applies, contact an authorized Audi dealer. 2019 Audi Group of America, Inc. and Audi Canada. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 2 of 77
Claim Entry Instructions
After campaign has been completed, enter claim as soon as possible to help prevent work from being duplicated
elsewhere. Attach the Elsa screen print showing action open on the day of repair to the repair order.
If customer refused campaign work:
 U.S. dealers: Submit the request through Audi Warranty Online under the Campaigns/Update option.
Service Number
23Z8
Damage Code
0099
Parts Vendor Code
Claim Type
002
Sold vehicle: 7 10
Unsold vehicle: 7 90
Causal Indicator
Vehicle Wash/Loaner
Mark Exhaust Pipe w/ Oxidation Catalyst and Diesel Particulate Filter* as causal part
Do not claim wash/loaner under this action. Please refer to Warranty Bulletin
AWA 19-05 for loaner vehicle claiming instructions.
Criteria I.D.
01, or 02, or 03
A6, A7, and Q5 Models: Install updated Exhaust Pipe w/ Oxidation Catalyst and
Diesel Particulate Filter and Oxygen Sensor.
Labor operation:
Quantity
2674 55 99
Part Number
1.00
4H0254750HX
1.00
4H0298099
1.00
04L906262B
260 T.U.
Description
Exhaust Pipe w/ Oxidation Catalyst and Diesel
Particulate Filter*
Installation Kit for Exhaust Pipe w/ Oxidation
Catalyst and Diesel Particulate Filter
Oxygen Sensor
--OR-A8 Models: Install updated Exhaust Pipe w/ Oxidation Catalyst and Diesel Particulate
Filter and Oxygen Sensor.
Labor operation:
Quantity
2674 56 99
Part Number
1.00
4H0254750HX
1.00
4H0298099
1.00
04L906262B
320 T.U.
Description
Exhaust Pipe w/ Oxidation Catalyst and Diesel
Particulate Filter*
Installation Kit for Exhaust Pipe w/ Oxidation
Catalyst and Diesel Particulate Filter
Oxygen Sensor
--AND ALL MODELS-Connect battery charger.
Labor operation:
2706 89 50
10 T.U.
--AND ALL MODELS-Connect vehicle diagnostic tester, perform software update for engine control unit.
Labor operation:
2360 25 99
Time stated on diagnostic protocol
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 3 of 77
Customer Letter Example (USA)
This notice applies to your vehicle: 
Subject:
Emissions Service Action 23Z8
3.0L TDI Engine – Emissions System Modification Correction (AEM-C)
2014-2016 Model Year Audi Q5, A6, A7 and A8/A8L with 3.0L TDI Engine (Generation 2 Passenger
Cars)
Dear Audi Owner,
As part of Audi’s ongoing commitment to customer satisfaction, we are informing you of our decision to conduct a service action on
certain 2014-2016 model year Audi 3.0L TDI (Gen 2 PC) vehicles that received an Approved Emissions Modification, or that will
eventually receive the Approved Emissions Modification, pursuant to the terms of Audi's Second Partial Consent Decree with the
Environmental Protection Agency, Department of Justice, California Air Resources Board, and California Attorney General. Our
records show that you are the owner of a vehicle affected by this action.
Information about this
Approved Emissions
Modification –
Correction (AEM-C)
What should you do?

To reduce soot accumulation related to the oxygen sensor, it is necessary to perform an AEM
Correction and replace and relocate the oxygen sensor to a different location in the exhaust
pipe. This soot accumulation may cause the sensor not to work effectively and could illuminate
your “check engine” light. Fixing this issue will require installation of a new diesel particulate
filter (DPF) with an improved oxygen sensor position. The DPF is in a part that also includes a
diesel oxidation catalyst (DOC) that will also be replaced as a result. In addition, as part of the
same service action, Audi is releasing a software update to the Approved Emissions Modification
(AEM) in order to improve on-board diagnostics (OBD) monitoring of vehicle emissions systems
and also improve the software used by your vehicle.

Updates in this service action will not adversely impact your vehicle’s drivability, features, fuel
economy, or warranty coverage.

Updates will take up to four (4) hours to complete, and will be performed for you free of charge.

Audi will provide you a loaner vehicle. You may also request alternate transportation during this
update.
If you elect to receive these updates, please contact your authorized Audi dealer as soon as possible to
schedule this service. Please keep in mind that your dealer may need additional time for the preparation
of the repair, as well as to accommodate their daily workshop schedule. For your convenience, you can
also visit www.audiusa.com and click on the “Find a Dealer” link to locate a dealer near you and schedule
this service. Before you receive these updates, you will be required to provide written authorization to
the Audi dealer.
This service action is voluntary. However, if you previously received an Approved Emissions
Modification and elect not to receive these updates to your vehicle, it may cause issues with your OBD
system and require a trip to an authorized Audi dealer to address.
If you already received an AEM and elect to receive these updates, you have two options:

Option 1: At your convenience, you may contact your nearest authorized Audi dealer and arrange
for an appointment to receive this service action update at no cost to you with your written
authorization.

Option 2: When you visit your Audi service department for any reason, including the “check engine”
light being illuminated due to this issue, the dealer can update your vehicle with your written
authorization.
Additionally, if you chose to receive an AEM, but have not yet received it, please contact your nearest
authorized Audi dealer for an appointment. The dealer will provide both the AEM and this AEM- C
during the same appointment with your written authorization.
Lease vehicles and
address changes
If you are the lessor and registered owner of the vehicle identified in this action, please forward this letter
immediately via first-class mail to the lessee within ten (10) days of receipt. If you have changed your
address or sold the vehicle, please fill out the enclosed prepaid Owner Reply card and mail it to us so
we can update our records.
Can we assist you
further?
If your authorized Audi dealer fails or is unable to complete this work free of charge within a reasonable
time, please contact Audi Customer Experience at 1-800-253-2834 or via our “Contact Us” page at
www.audiusa.com.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 4 of 77
Checking your vehicle
for open Recalls and
Service Campaigns
To check your vehicle’s eligibility for repair under this or any other recall/service campaign, please visit
the Recall/Service Campaign Lookup tool at www.audiusa.com and enter your Vehicle Identification
Number (VIN).
We apologize for any inconvenience this matter may cause; however we are taking this action to help ensure your vehicle continues
to meet your expectations and the requirements of Audi's Consent Decree with the United States and California.
Sincerely,
Audi Customer Protection
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 5 of 77
Campaign Work Procedure
23Z8 Emissions Service Action
NOTE

These repair instructions may differ from the labor operations and labor times listed in ELSA.

Damages resulting from improper repair or failure to follow these work instructions are the dealer’s
responsibility and are not eligible for reimbursement under this action.

This procedure must be read in its entirety prior to performing the repair.

Due to variations in vehicle equipment and options, the steps/illustrations in this work procedure may not
identically match all affected vehicles.

Diagnosis and repair of pre-existing conditions in the vehicle are not covered under this action.

When working during extreme temperatures, it is recommended that the vehicle be allowed to acclimate
inside the shop to avoid temperature-related component damage/breakage.
Repair Overview

Replace Exhaust Pipe w/ Oxidation Catalyst
and Diesel Particulate Filter with updated
version.

Replace Oxygen Sensor.

Update ECM software.
Required Parts
Criteria
Quantity
Part Number
01 or 02 or 03
1
4H0.254.750.HX
01 or 02 or 03
1
4H0.298.099
01 or 02 or 03
1
04L.906.262.B
Part Description
Exhaust Pipe w/ Oxidation Catalyst and
Diesel Particulate Filter
Installation Kit for Exhaust Pipe w/ Oxidation
Catalyst and Diesel Particulate Filter
(See Appendix A for kit contents)
Oxygen Sensor
NOTE
The specified part numbers reflect the status at the start of this recall. Interim updates made in ETKA can cause a
listed part number to become unavailable. In this case, the new part number specified in ETKA should be used.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 6 of 77
Required Tools
VAS6150D - Diagnostic
Tester
(or equivalent)
VAS6154 - Vehicle
Communication
Interface
GRX3000VAS – Battery
Tester/Charger
(or equivalent)
(or equivalent)
Diesel Engine Tool Set
- 17mm -T10395A-
Ring Wrench 7-Piece Set
-3337-
(or equivalent)
(or equivalent)
Torque Wrench 1332
40-200Nm -VAG 1332
Torque Wrench 1331
5-50Nm -VAG 1331
(or equivalent)
(or equivalent)
Wiper Arm Kit - Puller 1
-T10369/1
(or equivalent)
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 7 of 77
Repair Instruction
Section A - Check for Previous Repair

Enter the VIN in Elsa and proceed to the
“Campaign/Action” screen.
TIP
On the date of repair, print this screen and keep a copy
with the repair order.

Confirm the Campaign/Action is open .
If the status is closed, no further work is required.

Note the Applicable Criteria ID  for use
in determining the correct work to be done and
corresponding parts associated.

All safety recalls must be completed prior to
completing this Service Action.
Proceed to Section B
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 8 of 77
Section B – For All Criteria (01, 02, 03): A6 and A7 Vehicles, Replace Exhaust Pipe w/
Oxidation Catalyst and Diesel Particulate Filter
A6 and A7, Replace Exhaust Pipe w/ Oxidation
Catalyst and Diesel Particulate Filter
Remove rear noise insulation:

Secure and raise vehicle on hoist.

Remove the bolts <1>.

Loosen the quick-release fasteners <2 and 4>.

Remove the rear noise insulation <3>.
Remove lower exhaust nut:

Remove the nut <1>.
NOTE
The nuts <2> will be removed later from above.
Ignore item <3>.

Lower the vehicle on the hoist.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 9 of 77
Battery Disconnect:

Turn off the ignition.

Lift the luggage compartment floor covering by
the handle and fold it forward.

If equipped remove the vehicle tool kit.

Open the cover <3> over the battery negative
pole.

Loosen the nut <1> several turns and remove
the battery ground cable terminal <2> from the
battery terminal.
Remove engine cover:

Carefully pull the engine cover off the retaining
pins one after the other in direction of
. Do not pull sharply on the engine
cover or pull it to one side.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 10 of 77
Remove Plenum Chamber Cover:

Remove the seal <7>.

Lift the plenum chamber cover <3> far enough
so that the frame <4> is above the air intake
shroud <5> for the fresh air blower.

Remove the plenum chamber cover from the
cowl panel <6>.
NOTE
The tab <2> over the cover <1> will be damaged if
the seal is not removed first. Consequential damage
to the cowl cover or seal will not be covered under
this action.
Remove Tower Brace:

Remove the left and right expanding rivets
 and the nuts <2> and unclip the trim
cover <1>.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 11 of 77

Remove the five bolts <1, 2, and 3> and
remove the two screws .

Remove the tower brace from the vehicle.
Remove Plenum Chamber Bulkhead:

Release the retainer  and open the
cover  for the Terminal 30 Wire
Junction 2 -TV22-.

Remove the nut <3> and free up the wire.

Remove the connector  from the
bracket.

Remove the nuts  and then remove
Terminal 30 Wire Junction 2 -TV22- from the
plenum chamber bulkhead.

Free up the vacuum line and any remaining
wiring harness connections under the
Terminal 30 Wire Junction 2 -TV22-, and
secure them out of the way.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 12 of 77

Remove the heat shield <1> upward ,
if equipped.

Lift the seal in direction of 
enough to clear the wiring bushing.

Release the retaining clips  on
both sides of the wiring harness bushing and
remove it by lifting upward from the wiring
harness channel.

Free up the wiring harness from the plenum
chamber bulkhead enough to allow removal of
the bulkhead.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 13 of 77

Remove all of the bolts, nuts, or screws
 securing the plenum chamber
bulkhead to the chassis.
NOTE

Different numbers and types of fasteners
may be installed. There may be different
styles of cable brackets, clips, nuts, screws,
or bolts used to secure the plenum chamber
bulkhead to the chassis.

There also may be additional fasteners
hidden behind the aluminum heat shield on
some vehicles .

Once all securing fasteners are removed,
the plenum chamber bulkhead will freely
and easily separate from the chassis.

If the plenum chamber bulkhead does not
freely and easily separate from the chassis,
search for additional fasteners behind the
heat shielding.

Step on the brake pedal four or five times to
relieve the vacuum from the brake booster
system.

Remove the brake booster vacuum line <3>.

Remove the grommet <1> from the vacuum
connection.

Remove the plenum chamber bulkhead <4>
upwards from the chassis.
NOTE
Removing the brake booster vacuum line while
vacuum is still present in the booster system may
result in damage to the vacuum line or grommet.
Consequential damage to the vacuum line or
grommet will not be covered under this action.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 14 of 77
Exhaust Pipe w/ Oxidation Catalyst and Diesel
Particulate Filter sensor removal:
NOTE
The exhaust temperature sensors and NOx 1
sensor probes are very fragile. Use extreme care
when removing and handling the exhaust
temperature sensors and NOx 1 sensor to avoid
damage to the sensor probes.

Unscrew the exhaust temperature sensors <3
and 4>, Oxygen Sensor <2>, and NOx 1
sensor <1> and remove them from the exhaust
pipe with oxidation catalyst and diesel
particulate filter.

Disconnect the connector for the oxygen
sensor <2> and remove it from the bracket.
Discard the oxygen sensor <2>.

Set the exhaust temperature sensors <3 and
4> and NOx 1 sensor <1> aside in a safe place
to avoid damage to the sensor probes.
Remove Exhaust Pipe w/ Oxidation Catalyst and
Diesel Particulate Filter:

Remove the three nuts  securing the
exhaust pipe with oxidation catalyst and diesel
particulate filter to the turbocharger.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 15 of 77
Remove Differential Pressure Sensor Hose:

Using pliers, loosen the clamp  and
remove the differential pressure sensor hose
from the steel differential pressure tube.

Remove exhaust gas temperature sensor #4
 and set it aside in a safe
place to avoid damage to the sensor probe.
NOTE
The exhaust temperature sensor probe is very
fragile. Use extreme care when removing and
handling the exhaust temperature sensor to avoid
damage to the sensor probe.

Remove the two nuts  securing
the exhaust pipe with oxidation catalyst and
diesel particulate filter to the exhaust
downpipe.

Remove the exhaust pipe with oxidation
catalyst and diesel particulate filter from the
vehicle and discard the old gaskets.
Transfer Differential Pressure Pipe:

Loosen the nut on the differential pressure
pipe <1> and remove the pipe. Remove the
clip <2> from the old exhaust pipe. Disengage
the clip from the bottom using a small
screwdriver.

Install the differential pressure pipe <1> onto
the new exhaust pipe. Transfer the clip from
old exhaust pipe onto the new exhaust pipe,
and secure the pipe in the clip. Tighten the
differential pressure pipe nut to 45 Nm.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 16 of 77
Install new Exhaust Pipe w/ Oxidation Catalyst and
Diesel Particulate Filter:

Install the exhaust pipe gasket onto the lower
exhaust suds.

Install the turbocharger gasket onto the
turbocharger studs.

Install the new Exhaust Pipe w/ Oxidation
Catalyst and Diesel Particulate Filter into
vehicle with new gaskets and nuts.

Align the Exhaust Pipe w/ Oxidation Catalyst
and Diesel Particulate Filter onto the lower
exhaust studs first, then work the flange onto
the turbocharger studs.

Install two “Silver” colored shouldered hex nuts
 onto the lower studs securing the
exhaust downpipe to the exhaust pipe with
oxidation catalyst with diesel particulate filter.
Tighten the two “Silver” colored exhaust nuts
 to 23 Nm.

Install and tighten exhaust temperature sensor
#4  to 45 Nm.

Install the three “Copper” colored shouldered
hex nuts onto studs  at the flange
of the turbocharger. Tighten the “Copper”
colored exhaust nuts to 23 Nm.
Part Number
Part Description
4H0.254.750.HX
Exhaust Pipe w/ Oxidation
Catalyst and Diesel Particulate
Filter
Included in installation kit 4H0298099:
Part Number
Part Description
8K0.253.115.J
Gasket, Exhaust Pipe
4G0.253.115.A
Gasket, Turbocharger
N 911.308.02
Shouldered Hex Nut, selflocking – Exhaust Pipe (Silver,
exhaust downpipe flange)
N 911.308.01
Shouldered Hex Nut, selflocking – Turbocharger
(Copper, turbocharger flange)
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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Exhaust Pipe w/ Oxidation Catalyst and Diesel Particulate Filter Sensor installation:
CRITICAL REPAIR STEP
STOP!
Installing the four sensors listed below into their correct assigned locations is CRITICAL. Follow the numbered
and color coded sequence below to correctly install the sensors into their required assigned locations.

Install and tighten the four exhaust pipe sensors in the locations shown, in the following order:
1. The new Oxygen Sensor -G39-  is installed in the bung closest to the turbocharger, as
shown . Tighten the Oxygen Sensor -G39- to 52 Nm.

NOTE: The Oxygen Sensor -G39- will now be located BEFORE the NOx #1 Sensor in
the exhaust stream. Do not plug in the Oxygen Sensor wiring harness at this time.
Part Number
Part Description
04L.906.262.B
Oxygen Sensor -G39-
2. NOx #1 Sensor -G295-  is installed in the next downstream bung, as shown .
Tighten the NOx #1 Sensor to 52 Nm.

NOTE: NOx #1 Sensor will now be located AFTER the Oxygen Sensor -G39- in the
exhaust stream.
3. Exhaust Gas Temperature Sensor #2  is installed in the next downstream bung before
the oxidation catalyst, as shown .

NOTE: Exhaust Gas Temperature Sensor #2 has a “Curved” sensor probe. Tighten
the sensor to 45 Nm.
4. Exhaust Gas Temperature Sensor #3  is installed in the next downstream bung between
the oxidation catalyst and the diesel particulate filter, as shown .

NOTE: Exhaust Gas Temperature Sensor #3 has a “Straight” sensor probe. Tighten
the sensor to 45 Nm.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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Routing and Securing the New Oxygen Sensor
-G39- Wiring Harness:
CRITICAL REPAIR STEP
STOP!
Correctly routing and securing the new Oxygen
Sensor -G39- wiring harness is CRITICAL.
Failure to correctly route and secure the new
Oxygen Sensor -G39- wiring harness as described
in the steps below may result in chaffing of the
wiring harness, or inadvertently securing the wiring
harness to engine components that require isolation
for proper operation, such as high-pressure fuel
lines.

O2 sensor wiring harness routing procedure and tie
strap installation
Click on the following link or scan the QR
Code to view a short video detailing the O2
sensor wiring harness routing procedure
and tie strap installation.
https://audiexternal.kzoplatform.com:443/player/medium/147043
6762785421044?autoplay=on

Start by routing the new Oxygen Sensor -G39wiring harness under the main engine wiring
harness, as shown.
o
Make sure the new Oxygen Sensor
-G39- wiring harness is NOT routed
underneath any high-pressure fuel
injector lines during this procedure.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 19 of 77

Feed the new Oxygen Sensor -G39- wiring
harness  underneath the engine
wiring harness, Exhaust Gas Temperature
Sensor #2 wiring harness, and low-pressure
fuel return line  as shown.

Loosely route the new Oxygen Sensor -G39harness into the Zig-Zag position, as shown.

Balance the harness lengths on each loop as
necessary to achieve a uniform routing.
o

The harness should be routed loosely
with no kinks in the loop ends.
Place a small upward bend  on the end
of the grey high-temperature tie-strap included
in the 4H0.298.099 installation kit.
Included in installation kit 4H0298099:
Part Number
Part Description
N 909.377.02
Tie Strap
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
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
Insert the grey high-temperature tie-strap
under the furthest left guide pin on the engine
wiring harness bracket .

Visually inspect to make sure the tie-strap is
installed over the high-pressure fuel line
.

DO NOT insert the tie-strap into its retaining
clasp until proper alignment and routing has
been verified.
CRITICAL REPAIR STEP
STOP!
Do NOT route the tie-strap under the high-pressure
fuel line. Damage to the fuel line may occur.
Do NOT route the tie-strap under the furthest right
guide pin on the engine wiring harness bracket .

Before inserting the tie-strap into its retaining
clasp, verify that the tie-strap has been
properly routed around the upper two loops of
the harness, as shown. The lower loop should
NOT be captured by the tie-strap.

Adjust and balance the wiring harness loops
until a uniform sweeping Zig-Zag is created.

Slide the tie strap so that it is near the furthest
left guide pin , and lightly secure
the tie strap so that the harness can still be
adjusted if needed.

Once the wiring harness has been balanced
and the tie-strap has been properly positioned
against the furthest left guide pin , completely tighten the tie-strap.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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
Using a ruler or caliper, measure the length of
tie-strap that has passed through the securing
loop.
o
If the distance measured is greater
than 32mm , then the
tie-strap has likely been installed
correctly. The tie-strap should be
located near the furthest left locating
pin on the engine wiring harness
bracket.

o
Proceed to the next step for
final visual validation.
If the distance measured is less than
32mm, then the tie-strap has likely
been installed incorrectly.

Visually validate for correct
installation of the tie strap
before continuing with the
work procedure. If improperly
installed, remove the tie-strap
and repeat this procedure.
CRITICAL REPAIR STEP
STOP!
Final visual validation of proper tie-strap installation
is REQUIRED. Visually inspect the tie-strap routing
to verify there is no contact with engine components
that require isolation for proper operation, such as
high-pressure fuel lines, coolant lines, etc.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 22 of 77

Once proper routing and positioning has been
verified, cut off the remaining portion of the
tie-strap with cutters.
Install Differential Pressure Sensor hose:

Reattach the differential pressure sensor hose
to the steel differential pressure tube and
secure the clamp .
Install Plenum Chamber Bulkhead:

Reinstall the plenum chamber bulkhead <4>
ensuring the seal is correctly in place.

Install the nut <2> and tighten to 4 Nm.

Reinstall the vacuum hose and grommet <1>
from the brake booster system onto the
bulkhead.
NOTE
Different types of fasteners <2> may be installed.
There can be a cable bracket, clip or bolt. There
also may be additional fasteners behind the
aluminum heat shield on some vehicles. Reinstall
the fasteners into the positions they were removed
from.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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
Reinstall all removed fasteners securing the
plenum chamber bulkhead  and
tighten to 2 Nm.
NOTE
Different types of fasteners may be installed. There
can be a cable bracket, clip, nut, or bolt. There also
may be additional fasteners behind the aluminum
heat shield on some vehicles.
Reinstall all fasteners into the locations they were
removed from.

Insert the wiring harness into the slot on the
plenum chamber bulkhead.

Install the wiring bushing downward in the
direction of  and secure the tabs
.

Install the seal onto the wiring bushing in the
direction of .
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 24 of 77

Install the heat shield <1> downward in
opposite direction of , if equipped.
Install Terminal 30 Wire Junction 2 -TV22-:

Secure the vacuum line and any wiring
harness connections that are located under
the Terminal 30 Wire Junction 2 -TV22- and
fasten the clips .

Install the Terminal 30 Wire Junction Box.
Install the nuts  and tighten to 3 Nm.

Install the wire onto the stud. Install the nut
<3> and tighten to 3 Nm.

Close the cover on the Terminal 30 Wire
Junction 2 -TV22- and secure the tab
.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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Install Tower Brace:

Install the tower brace.

Install the five bolts <1, 2, and 3> and tighten
to 20 Nm.

Install the screws  and tighten to
2 Nm.

Install the left and right trim covers <1>.

Install the left and right expanding rivets
 and the nuts <2> and tighten to 2.5
Nm.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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Install Plenum Chamber Cover:

Install the plenum chamber cover <3> onto the
cowl panel <6>.

Install the seal <7> and ensure it is firmly in
place.
NOTE
Ensure the tabs <2> are seated correctly on the
cowl panel before installing the seal <7>.
Consequential damage to the cowl cover or seal will
not be covered under this action.
Install Engine Cover:

Install the engine cover and carefully press
down in the opposite direction of  one
corner at a time to secure the engine cover into
the retaining pins.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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Connect Battery:

Lift the luggage compartment floor covering by
the handle and fold it forward.

If equipped remove the vehicle tool kit.

Open the cover <3> over the battery negative
pole and install the battery ground terminal
onto the negative battery post.

Tighten the nut <1> to 5 Nm.

Reinstall the vehicle tool kit, and fold the floor
covering back into place.
Install Lower Exhaust Nut:

Raise the vehicle on the hoist.

Install the remaining “Silver” colored
shouldered hex nut (N 911.308.02) <1> and
tighten to 23 Nm.
Included in installation kit 4H0298099:
Part Number
Part Description
N 911.308.02
Shouldered Hex Nut, selflocking – Silver, exhaust
downpipe flange
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 28 of 77
Install Rear Noise Insulation:

Install the rear noise insulation <3>.

Install the bolts <1> and tighten to 3.5 Nm.

Install the quick-release fasteners <2 and 4>.

Lower vehicle on hoist.
Parts Return / Disposal:
Exhaust Pipe w/ Oxidation Catalyst and Diesel
Particulate Filter:

The Exhaust Pipe w/ Oxidation Catalyst and
Diesel Particulate Filter must be tagged with a
blue zip tie  and returned in order
to be considered for core charge
reimbursement.
All other parts:

Properly store (retain), destroy or dispose of
removed parts in accordance with all state and
local requirements, unless otherwise indicated
and/or requested through the Warranty Parts
Portal (WPP).
Proceed to Section E (Software Update).
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 29 of 77
Section C – For All Criteria (01, 02, 03): A8 Vehicles, Replace Exhaust Pipe w/ Oxidation
Catalyst and Diesel Particulate Filter
A8, Replace Exhaust Pipe w/ Oxidation Catalyst
and Diesel Particulate Filter
Remove Rear Noise Insulation:

Secure and raise vehicle on hoist.

Remove the quick releases <5 and 6> that
connect the rear section of the front wheel
housing and the rear noise insulation.

Remove the quick releases <4> from the front
noise insulation <3>.

Remove the quick release bolts <2, 7 and 8>.
Remove Lower Exhaust Nut:

Remove the nut <1>.
NOTE
The nuts <2> will be removed later from above.
Ignore item <3>.

Lower the vehicle on the hoist.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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Battery Disconnect:

Turn off the ignition.

Lift the luggage compartment floor covering by
the handle and fold it forward.

If equipped remove the vehicle tool kit.

Open the cover <3> over the battery negative
pole.

Loosen the nut <1> several turns and remove
the battery ground cable terminal <2> from the
battery terminal.
Remove Engine Cover:

Carefully pull the engine cover off the retaining
pins one after the other in direction of
. Do not pull sharply on the engine
cover or pull it to one side.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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Remove Plenum Chamber Cover:

Mark the resting position of the windshield
wiper arms with masking tape (or equivalent).

Remove windshield wiper arms using Wiper
Arm Kit - Puller 1 - T10369/1.

Remove hood seal in area around the plenum
chamber cover.

Remove bolts <3 and 5> and release the
corner covers <4 and 8>.
NOTE
For easier removal/installation, spray the windshield
edge strip <7> with soapy solution.

Remove plenum chamber cover panel <1>
upward diagonally from edge frame beginning
at window edge.
CAUTION
Risk of windshield glass breaking during
removal/installation:


Do not hit or use excessive force on the trim
when removing or installing.

Carefully remove or install the trim
sideways, beginning in the edge frame.

Damage to the windshield glass or plenum
chamber cover will not be covered under
this action.
Unclip the plenum chamber cover <1> from
the side covers starting on the left and right
sides and then remove it.
Remove Tower Brace:

Free up the left and right wiring harnesses
from the plenum chamber bulkhead by
releasing the retainers  and
removing the harnesses from the plenum
chamber bulkhead.

Remove the connectors <1> from the bracket
and disconnect them.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 32 of 77

If installed, remove the nuts  and
move the E-box <1> to the side.

Free up the coolant hose <2> at the tower
brace.

Free up the wiring harness connections on the
tower brace.

Remove the bolts <1, 2, 3, and arrows> and
remove the tower brace.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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Remove Plenum Chamber Bulkhead:

Free up any remaining wiring harness
connections, vacuum lines, or other items
secured to the top of the plenum chamber
bulkhead.

Step on the brake pedal four or five times to
release the vacuum in the brake booster
system to ease vacuum line removal.

Remove the vacuum line from the grommet in
the bulkhead.

Remove the expanding clips <1> and bolts
<4>.
NOTE
Removing the brake booster vacuum line while
vacuum is still present in the booster system may
result in damage to the vacuum line or grommet.
Consequential damage to the vacuum line or
grommet will not be covered under this action.
Exhaust Pipe w/ Oxidation Catalyst and Diesel
Particulate Filter sensor removal:
NOTE
The exhaust temperature sensors and NOx 1
sensor probes are very fragile. Use extreme care
when removing and handling the exhaust
temperature sensors and NOx 1 sensor to avoid
damage to the sensor probes.

Unscrew the exhaust temperature sensors <3
and 4>, Oxygen Sensor <2>, and NOx 1
sensor <1> and remove them from the exhaust
pipe with oxidation catalyst and diesel
particulate filter.

Disconnect the connector for the oxygen
sensor <2> and remove it from the bracket.
Discard the oxygen sensor <2>.

Set the exhaust temperature sensors <3 and
4> and NOx 1 sensor <1> aside in a safe place
to avoid damage to the sensor probes.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 34 of 77
Remove Exhaust Pipe w/ Oxidation Catalyst and
Diesel Particulate Filter:

Remove the three nuts  securing the
exhaust pipe with oxidation catalyst and diesel
particulate filter to the turbocharger.
Remove Differential Pressure Sensor Hose:

Using pliers, loosen the clamp  and
remove the differential pressure sensor hose
from the steel differential pressure tube.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 35 of 77

Remove exhaust gas temperature sensor #4
 and set it aside in a safe
place to avoid damage to the sensor probe.
NOTE
The exhaust temperature sensor probe is very
fragile. Use extreme care when removing and
handling the exhaust temperature sensor to avoid
damage to the sensor probe.

Remove the two nuts  securing
the exhaust pipe with oxidation catalyst and
diesel particulate filter to the exhaust
downpipe.

Remove the exhaust pipe with oxidation
catalyst and diesel particulate filter from the
vehicle and discard the old gaskets.
Transfer Differential Pressure Pipe:

Loosen the nut on the differential pressure
pipe <1> and remove the pipe. Remove the
clip <2> from the old exhaust pipe. Disengage
the clip from the bottom using a small
screwdriver.

Install the differential pressure pipe <1> onto
the new exhaust pipe. Transfer the clip from
old exhaust pipe onto the new exhaust pipe,
and secure the pipe in the clip. Tighten the
differential pressure pipe nut to 45 Nm.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 36 of 77
Install new Exhaust Pipe w/ Oxidation Catalyst and
Diesel Particulate Filter:

Install the exhaust pipe gasket onto the lower
exhaust suds.

Install the turbocharger gasket onto the
turbocharger studs.

Install the new Exhaust Pipe w/ Oxidation
Catalyst and Diesel Particulate Filter into
vehicle with new gaskets and nuts.

Align the Exhaust Pipe w/ Oxidation Catalyst
and Diesel Particulate Filter onto the lower
exhaust studs first, then work the flange onto
the turbocharger studs.

Install two “Silver” colored shouldered hex nuts
(N 911.308.02)  onto the lower
studs securing the exhaust downpipe to the
exhaust pipe with oxidation catalyst with diesel
particulate filter. Tighten the two “Silver”
colored exhaust nuts  to 23 Nm.

Install and tighten exhaust temperature sensor
#4  to 45 Nm.

Install the three “Copper” colored shouldered
hex nuts (N
911.308.01) onto studs
 at the flange of the turbocharger.
Tighten the “Copper” colored exhaust nuts to
23 Nm.
Part Number
Part Description
4H0.254.750.HX
Exhaust Pipe w/ Oxidation
Catalyst and Diesel Particulate
Filter
Included in installation kit 4H0298099:
Part Number
Part Description
8K0.253.115.J
Gasket, Exhaust Pipe
4G0.253.115.A
Gasket, Turbocharger
N 911.308.02
Shouldered Hex Nut, selflocking – Exhaust Pipe (Silver,
exhaust downpipe flange)
N 911.308.01
Shouldered Hex Nut, selflocking – Turbocharger
(Copper, turbocharger flange)
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 37 of 77
Exhaust Pipe w/ Oxidation Catalyst and Diesel Particulate Filter Sensor installation:
CRITICAL REPAIR STEP
STOP!
Installing the four sensors listed below into their correct assigned locations is CRITICAL. Follow the numbered
and color coded sequence below to correctly install the sensors into their required assigned locations.

Install and tighten the four exhaust pipe sensors in the locations shown, in the following order:
1. The new Oxygen Sensor -G39-  is installed in the bung closest to the turbocharger, as
shown . Tighten the Oxygen Sensor -G39- to 52 Nm.

NOTE: The Oxygen Sensor -G39- will now be located BEFORE the NOx #1 Sensor in
the exhaust stream. Do not plug in the Oxygen Sensor wiring harness at this time.
Part Number
Part Description
04L.906.262.B
Oxygen Sensor -G39-
2. NOx #1 Sensor -G295-  is installed in the next downstream bung, as shown .
Tighten the NOx #1 Sensor to 52 Nm.

NOTE: NOx #1 Sensor will now be located AFTER the Oxygen Sensor -G39- in the
exhaust stream.
3. Exhaust Gas Temperature Sensor #2  is installed in the next downstream bung before
the oxidation catalyst, as shown .

NOTE: Exhaust Gas Temperature Sensor #2 has a “Curved” sensor probe. Tighten
the sensor to 45 Nm.
4. Exhaust Gas Temperature Sensor #3  is installed in the next downstream bung between
the oxidation catalyst and the diesel particulate filter, as shown .

NOTE: Exhaust Gas Temperature Sensor #3 has a “Straight” sensor probe. Tighten
the sensor to 45 Nm.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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Routing and Securing the New Oxygen Sensor
-G39- Wiring Harness:
CRITICAL REPAIR STEP
STOP!
Correctly routing and securing the new Oxygen
Sensor -G39- wiring harness is CRITICAL.
Failure to correctly route and secure the new
Oxygen Sensor -G39- wiring harness as described
in the steps below may result in chaffing of the
wiring harness, or inadvertently securing the wiring
harness to engine components that require isolation
for proper operation, such as high-pressure fuel
lines.

O2 sensor wiring harness routing procedure and tie
strap installation
Click on the following link or scan the QR
Code to view a short video detailing the O2
sensor wiring harness routing procedure
and tie strap installation.
https://audiexternal.kzoplatform.com:443/player/medium/147043
6762785421044?autoplay=on

Start by routing the new Oxygen Sensor -G39wiring harness under the main engine wiring
harness, as shown.
o
Make sure the new Oxygen Sensor
-G39- wiring harness is NOT routed
underneath any high-pressure fuel
injector lines during this procedure.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 39 of 77

Feed the new Oxygen Sensor -G39- wiring
harness  underneath the engine
wiring harness, Exhaust Gas Temperature
Sensor #2 wiring harness, and low-pressure
fuel return line  as shown.

Loosely route the new Oxygen Sensor -G39harness into the Zig-Zag position, as shown.

Balance the harness lengths on each loop as
necessary to achieve a uniform routing.
o

The harness should be routed loosely
with no kinks in the loop ends.
Place a small upward bend  on the end
of the grey high-temperature tie-strap included
in the 4H0.298.099 installation kit.
Included in installation kit 4H0298099:
Part Number
Part Description
N 909.377.02
Tie Strap
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 40 of 77

Insert the grey high-temperature tie-strap
under the furthest left guide pin on the engine
wiring harness bracket .

Visually inspect to make sure the tie-strap is
installed over the high-pressure fuel line
.

DO NOT insert the tie-strap into its retaining
clasp until proper alignment and routing has
been verified.
CRITICAL REPAIR STEP
STOP!
Do NOT route the tie-strap under the high-pressure
fuel line. Damage to the fuel line may occur.
Do NOT route the tie-strap under the furthest right
guide pin on the engine wiring harness bracket .

Before inserting the tie-strap into its retaining
clasp, verify that the tie-strap has been
properly routed around the upper two loops of
the harness, as shown. The lower loop should
NOT be captured by the tie-strap.

Adjust and balance the wiring harness loops
until a uniform sweeping Zig-Zag is created.

Slide the tie strap so that it is near the furthest
left guide pin , and lightly secure
the tie strap so that the harness can still be
adjusted if needed.

Once the wiring harness has been balanced
and the tie-strap has been properly positioned
against the furthest left guide pin , completely tighten the tie-strap.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 41 of 77

Using a ruler or caliper, measure the length of
tie-strap that has passed through the securing
loop.
o
If the distance measured is greater
than 32mm , then the
tie-strap has likely been installed
correctly. The tie-strap should be
located near the furthest left locating
pin on the engine wiring harness
bracket.

o
Proceed to the next step for
final visual validation.
If the distance measured is less than
32mm, then the tie-strap has likely
been installed incorrectly.

Visually validate for correct
installation of the tie strap
before continuing with the
work procedure. If improperly
installed, remove the tie-strap
and repeat this procedure.
CRITICAL REPAIR STEP
STOP!
Final visual validation of proper tie-strap installation
is REQUIRED. Visually inspect the tie-strap routing
to verify there is no contact with engine components
that require isolation for proper operation, such as
high-pressure fuel lines, coolant lines, etc.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 42 of 77

Once proper routing and positioning has been
verified, cut off the remaining portion of the
tie-strap with cutters.
Install Differential Pressure Sensor hose:

Reattach the differential pressure sensor hose
to the steel differential pressure tube and
secure the clamp .
Install Plenum Chamber Bulkhead:

Install Plenum Chamber Bulkhead <3> making
sure the seal contacts the firewall correctly
.

Install the expanding clips <1> and bolts <4>
and torque to 10 Nm.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 43 of 77
Install Tower Brace:

Install Tower Brace and the bolts <1, 2, 3, and
arrows>.

Tighten the bolts as follows:
o
<1 and 3> = 50 Nm
o
<2> = 25 Nm
o
 = 10 Nm

Install the coolant hose <2> into securing tab
at the tower brace.

Connect and secure all remaining wiring
harness and vacuum line connections. Secure
all retaining tabs onto the tower brace and
bulkhead.

Install the E-box <1>. Install and tighten the
nuts  to 3 Nm.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 44 of 77

Install the left and right wiring harnesses into
the openings in the plenum chamber bulkhead
and secure the retainers .

Connect the connectors <1> and secure them
onto the brackets.
Install Plenum Chamber Cover:

Install plenum chamber cover panel <1>
inward diagonally from edge frame beginning
at window edge.

Install corner trim pieces <4 and 8> and install
the bolts. Tighten the bolts <3> to 3 Nm.
Tighten the bolts <5> to 6 Nm.
NOTE
For easier removal/installation, spray windshield
edge strip  with soapy solution.
CAUTION
Risk of windshield glass breaking during
removal/installation:

Do not hit or use excessive force on the trim
when removing or installing.

Carefully remove or install the trim
sideways, beginning in the edge frame.

Damage to the windshield glass or plenum
chamber cover will not be covered under
this action.

Seat the plenum chamber cover <1> into the
lip edge on the bottom of the windshield 

Install hood seal in area around the plenum
chamber cover.

Install windshield wiper arms using previous
markings to align them. Torque the nuts to 21
Nm.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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Install Engine Cover:

Install the engine cover and carefully press
down in the opposite direction of  one
corner at a time to secure the engine cover into
the retaining pins.
Connect Battery:

Lift the luggage compartment floor covering by
the handle and fold it forward.

If equipped remove the vehicle tool kit.

Open the cover <3> over the battery negative
pole and install the battery ground terminal
onto the negative battery post.

Tighten the nut <1> to 5 Nm.

Reinstall the vehicle tool kit, and fold the floor
covering back into place.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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Install Lower Exhaust Nut:

Raise the vehicle on the hoist.

Install the remaining “Silver” colored
shouldered hex nut (N 911.308.02) <1> and
tighten to 23 Nm.
Included in installation kit 4H0298099:
Part Number
Part Description
N 911.308.02
Shouldered Hex Nut, selflocking – Silver, exhaust
downpipe flange
Install Rear Noise Insulation:

Install the rear noise insulation <1>.

Install the bolts <4> and tighten to 3.5 Nm.

Install
the
<2, 7, and 8>.

Lower vehicle on hoist.
quick-release
fasteners
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 47 of 77
Parts Return / Disposal:
Exhaust Pipe w/ Oxidation Catalyst and Diesel
Particulate Filter:

The Exhaust Pipe w/ Oxidation Catalyst and
Diesel Particulate Filter must be tagged with a
blue zip tie  and returned in order
to be considered for core charge
reimbursement.
All other parts:

Properly store (retain), destroy or dispose of
removed parts in accordance with all state and
local requirements, unless otherwise indicated
and/or requested through the Warranty Parts
Portal (WPP).
Proceed to Section E (Software Update).
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 48 of 77
Section D – For All Criteria (01, 02, 03): Q5 vehicles, Exhaust Pipe w/ Oxidation Catalyst
and Diesel Particulate Filter
Q5, Replace Exhaust Pipe w/ Oxidation Catalyst
and Diesel Particulate Filter
Remove Rear Noise Insulation:

Secure and raise vehicle on hoist.

Remove the bolts <7 and 8>.

Remove the rivets <6>.

Remove the rear noise insulation <1>.
Remove Lower Exhaust Nut:

Remove the nut <1>.
NOTE
The nuts <2> will be removed later from above.
Ignore item <3>.

Lower the vehicle on the hoist.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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Battery Disconnect:

Turn off the ignition and remove the key.

Remove the luggage compartment floor
covering <3>.

Remove the dirt tray, if applicable.

If equipped, remove the subwoofer <2>.

Fold back the carpet <1> over the cover.

Unlock the retaining tabs  and open
the cover <1>.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 50 of 77

Open the cover <1> over the battery negative
terminal.

Loosen the nut several turns and remove the
battery ground cable terminal  from
the battery pole.
Remove Engine Cover:

Carefully pull the engine cover off the retaining
pins one after the other in direction of
. Do not pull sharply on the engine
cover or pull it to one side.
Remove NOx Sensor Module and/or Bracket:

On the driver side strut tower, disconnect the
connector for the NOx Sensor 1 Module
.
NOTE
Some bracket variation exists between vehicle
models. Photo shown may not match all vehicle
configurations.

Unscrew either the two nuts securing the NOx
Module to the bracket, or the two nuts securing
the mounting bracket to chassis  and
remove the module and/or bracket and set it
aside. Remove component/s as needed to
provide clearance for cowl panel removal.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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Remove Tower Brace:

Remove the four nuts <2>, two bolts <3>, and
the two speed-nuts <5>. Remove the tower
brace <1>.
NOTE
The bolts <6> do not require removal.
Remove Plenum Chamber Bulkhead:

Remove the upper cowl seal .

Open the battery jump post access cover.

Using a screwdriver or hook tool, carefully
release the tabs  on the
cowl cover .

Remove the cowl cover panel from the cowl.
NOTE
The tabs  on the cowl cover will
be damaged if not carefully and completely
disconnected before removal of the panel.
Consequential damage to the cowl cover will not be
covered under this action.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 52 of 77

Depress the vehicle brake pedal four or five
times to relieve vacuum from the brake
booster system.

Remove the brake booster vacuum line
 and remove the grommet from the
vacuum connection.
NOTE
Removing the brake booster vacuum line while
vacuum is still present in the booster system may
result in damage to the vacuum line or grommet.
Consequential damage to the vacuum line or
grommet will not be covered under this action.

Using a small screwdriver, disconnect all of the
cable tie connectors  from the battery
cables and wiring harness on the back side of
the plenum chamber.
NOTE
Different types and configurations of cable fasteners
may be installed. There are multiple fasteners on
the driver and passenger side of the bulkhead.
Verify that all fasteners have been removed before
removing the plenum chamber bulkhead.

Using a small screwdriver, remove the cap
 from the bolt on the battery positive
terminal 30 carrier.

Remove the bolt.

Lift the right side of the terminal block, and
slide to the right to disconnect the tabs from
the support bracket.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 53 of 77

Using pliers, squeeze the tabs on the wiring
harness securing tab , and remove the
tab from the support bracket.

Release the retainers  from the
securing tabs  and remove the wiring
bushing upward out of the plenum chamber
bulkhead.

Remove all fasteners securing the plenum
chamber bulkhead cover to the firewall.
NOTE

Different types of fasteners may be installed
in different locations. There may be cable
brackets, clips, nuts, or bolts. This fastener
configuration may vary based on vehicle
model.

Some
push-type
fasteners
require
squeezing the tabs from the back side of the
bulkhead with pliers  to remove.

Use care when working so you do not
damage the fasteners during removal.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 54 of 77

Remove the plenum chamber bulkhead
upward (bulkhead shown removed).

Secure all disconnected wiring harness
connections, hoses, and cables out of the way
with a tie strap (or equivalent).
Exhaust Pipe w/ Oxidation Catalyst and Diesel
Particulate Filter sensor removal:
NOTE
The exhaust temperature sensors and NOx 1
sensor probes are very fragile. Use extreme care
when removing and handling the exhaust
temperature sensors and NOx 1 sensor to avoid
damage to the sensor probes.

Unscrew the exhaust temperature sensors <3
and 4>, Oxygen Sensor <2>, and NOx 1
sensor <1> and remove them from the exhaust
pipe with oxidation catalyst and diesel
particulate filter.

Disconnect the connector for the oxygen
sensor <2> and remove it from the bracket.
Discard the oxygen sensor <2>.

Set the exhaust temperature sensors <3 and
4> and NOx 1 sensor <1> aside in a safe place
to avoid damage to the sensor probes.
Remove Exhaust Pipe w/ Oxidation Catalyst and
Diesel Particulate Filter:

Remove the three nuts  securing the
exhaust pipe with oxidation catalyst and diesel
particulate filter to the turbocharger.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 55 of 77
Remove Differential Pressure Sensor Hose:

Using pliers, loosen the clamp  and
remove the differential pressure sensor hose
from the steel differential pressure tube.

Remove exhaust gas temperature sensor #4
 and set it aside in a safe
place to avoid damage to the sensor probe.
NOTE
The exhaust temperature sensor probe is very
fragile. Use extreme care when removing and
handling the exhaust temperature sensor to avoid
damage to the sensor probe.

Remove the two nuts  securing
the exhaust pipe with oxidation catalyst and
diesel particulate filter to the exhaust
downpipe.

Remove the exhaust pipe with oxidation
catalyst and diesel particulate filter from the
vehicle and discard the old gaskets.
Transfer Differential Pressure Pipe:

Loosen the nut on the differential pressure
pipe <1> and remove the pipe. Remove the
clip <2> from the old exhaust pipe. Disengage
the clip from the bottom using a small
screwdriver.

Install the differential pressure pipe <1> onto
the new exhaust pipe. Transfer the clip from
old exhaust pipe onto the new exhaust pipe,
and secure the pipe in the clip. Tighten the
differential pressure pipe nut to 45 Nm.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 56 of 77
Install new Exhaust Pipe w/ Oxidation Catalyst and
Diesel Particulate Filter:

Install the exhaust pipe gasket onto the lower
exhaust suds.

Install the turbocharger gasket onto the
turbocharger studs.

Install the new Exhaust Pipe w/ Oxidation
Catalyst and Diesel Particulate Filter into
vehicle with new gaskets and nuts.

Align the Exhaust Pipe w/ Oxidation Catalyst
and Diesel Particulate Filter onto the lower
exhaust studs first, then work the flange onto
the turbocharger studs.

Install two “Silver” colored shouldered hex nuts
(N 911.308.02)  onto the lower
studs securing the exhaust downpipe to the
exhaust pipe with oxidation catalyst with diesel
particulate filter. Tighten the two “Silver”
colored exhaust nuts  to 23 Nm.

Install and tighten exhaust temperature sensor
#4  to 45 Nm.

Install the three “Copper” colored shouldered
hex nuts (N
911.308.01) onto studs
 at the flange of the turbocharger.
Tighten the “Copper” colored exhaust nuts to
23 Nm.
Part Number
Part Description
4H0.254.750.HX
Exhaust Pipe w/ Oxidation
Catalyst and Diesel
Particulate Filter
Included in installation kit 4H0298099:
Part Number
Part Description
8K0.253.115.J
Gasket, Exhaust Pipe
4G0.253.115.A
Gasket, Turbocharger
N 911.308.02
Shouldered Hex Nut, selflocking – Exhaust Pipe
(Silver, exhaust downpipe
flange)
N 911.308.01
Shouldered Hex Nut, selflocking – Turbocharger
(Copper, turbocharger
flange)
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 57 of 77
Exhaust Pipe w/ Oxidation Catalyst and Diesel Particulate Filter Sensor installation:
CRITICAL REPAIR STEP
STOP!
Installing the four sensors listed below into their correct assigned locations is CRITICAL. Follow the numbered
and color coded sequence below to correctly install the sensors into their required assigned locations.

Install and tighten the four exhaust pipe sensors in the locations shown, in the following order:
1. The new Oxygen Sensor -G39-  is installed in the bung closest to the turbocharger, as
shown . Tighten the Oxygen Sensor -G39- to 52 Nm.

NOTE: The Oxygen Sensor -G39- will now be located BEFORE the NOx #1 Sensor in
the exhaust stream. Do not plug in the Oxygen Sensor wiring harness at this time.
Part Number
Part Description
04L.906.262.B
Oxygen Sensor -G39-
2. NOx #1 Sensor -G295-  is installed in the next downstream bung, as shown .
Tighten the NOx #1 Sensor to 52 Nm.

NOTE: NOx #1 Sensor will now be located AFTER the Oxygen Sensor -G39- in the
exhaust stream.
3. Exhaust Gas Temperature Sensor #2  is installed in the next downstream bung before
the oxidation catalyst, as shown .

NOTE: Exhaust Gas Temperature Sensor #2 has a “Curved” sensor probe. Tighten
the sensor to 45 Nm.
4. Exhaust Gas Temperature Sensor #3  is installed in the next downstream bung between
the oxidation catalyst and the diesel particulate filter, as shown .

NOTE: Exhaust Gas Temperature Sensor #3 has a “Straight” sensor probe. Tighten
the sensor to 45 Nm.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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Routing and Securing the New Oxygen Sensor
-G39- Wiring Harness:
CRITICAL REPAIR STEP
STOP!
Correctly routing and securing the new Oxygen
Sensor -G39- wiring harness is CRITICAL.
Failure to correctly route and secure the new
Oxygen Sensor -G39- wiring harness as described
in the steps below may result in chaffing of the
wiring harness, or inadvertently securing the wiring
harness to engine components that require isolation
for proper operation, such as high-pressure fuel
lines.

O2 sensor wiring harness routing procedure and tie
strap installation
Click on the following link or scan the QR
Code to view a short video detailing the O2
sensor wiring harness routing procedure
and tie strap installation.
https://audiexternal.kzoplatform.com:443/player/medium/147043
6762785421044?autoplay=on

Start by routing the new Oxygen Sensor -G39wiring harness under the main engine wiring
harness, as shown.
o
Make sure the new Oxygen Sensor
-G39- wiring harness is NOT routed
underneath any high-pressure fuel
injector lines during this procedure.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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
Feed the new Oxygen Sensor -G39- wiring
harness  underneath the engine
wiring harness, Exhaust Gas Temperature
Sensor #2 wiring harness, and low-pressure
fuel return line  as shown.

Loosely route the new Oxygen Sensor -G39harness into the Zig-Zag position, as shown.

Balance the harness lengths on each loop as
necessary to achieve a uniform routing.
o

The harness should be routed loosely
with no kinks in the loop ends.
Place a small upward bend  on the end
of the grey high-temperature tie-strap included
in the 4H0.298.099 installation kit.
Included in installation kit 4H0298099:
Part Number
Part Description
N 909.377.02
Tie Strap
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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
Insert the grey high-temperature tie-strap
under the furthest left guide pin on the engine
wiring harness bracket .

Visually inspect to make sure the tie-strap is
installed over the high-pressure fuel line
.

DO NOT insert the tie-strap into its retaining
clasp until proper alignment and routing has
been verified.
CRITICAL REPAIR STEP
STOP!
Do NOT route the tie-strap under the high-pressure
fuel line. Damage to the fuel line may occur.
Do NOT route the tie-strap under the furthest right
guide pin on the engine wiring harness bracket .

Before inserting the tie-strap into its retaining
clasp, verify that the tie-strap has been
properly routed around the upper two loops of
the harness, as shown. The lower loop should
NOT be captured by the tie-strap.

Adjust and balance the wiring harness loops
until a uniform sweeping Zig-Zag is created.

Slide the tie strap so that it is near the furthest
left guide pin , and lightly secure
the tie strap so that the harness can still be
adjusted if needed.

Once the wiring harness has been balanced
and the tie-strap has been properly positioned
against the furthest left guide pin , completely tighten the tie-strap.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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
Using a ruler or caliper, measure the length of
tie-strap that has passed through the securing
loop.
o
If the distance measured is greater
than 32mm , then the
tie-strap has likely been installed
correctly. The tie-strap should be
located near the furthest left locating
pin on the engine wiring harness
bracket.

o
Proceed to the next step for
final visual validation.
If the distance measured is less than
32mm, then the tie-strap has likely
been installed incorrectly.

Visually validate for correct
installation of the tie strap
before continuing with the
work procedure. If improperly
installed, remove the tie-strap
and repeat this procedure.
CRITICAL REPAIR STEP
STOP!
Final visual validation of proper tie-strap installation
is REQUIRED. Visually inspect the tie-strap routing
to verify there is no contact with engine components
that require isolation for proper operation, such as
high-pressure fuel lines, coolant lines, etc.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 62 of 77

Once proper routing and positioning has been
verified, cut off the remaining portion of the
tie-strap with cutters.
Install Differential Pressure Sensor hose:

Reattach the differential pressure sensor hose
to the steel differential pressure tube and
secure the clamp .
Install Plenum Chamber Bulkhead:

Work the plenum chamber bulkhead into
position between the firewall and the exhaust
pipe.

Insert the plenum chamber bulkhead into the
clip on the firewall, and verify that the heat
shield has not been deformed during removal
or reinstallation.

If the heat shield has been deformed,
reposition it before securing the bulkhead to
the clip.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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
Install all fasteners securing the plenum
chamber bulkhead cover to the firewall.
Torque fasteners to 2 Nm.
NOTE

Different types of fasteners may be installed
in different locations. There may be cable
brackets, clips, nuts, or bolts. This fastener
configuration may vary based on vehicle
model.

Use care when working so you do not
damage the fasteners during installation.

Install the wiring harness grommet into the
plenum chamber bulkhead.

Insert the wiring harness bulkhead cover
between the bulkhead and firewall and secure
the tabs  into the retainers .

Insert the wiring harness securing tab ,
into the support bracket beneath the battery
positive terminal 30 carrier -TV22-.
TIP
Use pliers to guide the securing tab up through the
bracket, as there is limited clearance under the
bracket to push from below.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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
Install the battery positive terminal 30 carrier
-TV22- by inserting the terminal block into the
bracket tabs, and slide to the left to secure the
tabs into the support bracket.

Install the bolt and tighten to 7.5 Nm.

Install the cap  onto the bolt on the
battery positive terminal 30 carrier -TV22-.

Install the brake booster vacuum line 
into the grommet for the vacuum connection.

Reconnect all of the cable tie connectors
 from the battery cables and wiring
harness onto the back side of the plenum
chamber bulkhead.
NOTE
Different types and configurations of cable fasteners
may be installed. There are multiple fasteners on
the driver and passenger side of the bulkhead.
Verify that all fasteners have been reinstalled and
all harnesses and cables are secure.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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Install Cowl Cover Panel:

Insert the lip on the cowl cover panel <2> into
the channel on the wiper cowl cover panel
<1>. Work the panel back and forth until the
lip is fully seated into the channel.

Carefully insert the tabs on the cowl cover
 into the slots on the
bulkhead .

Use a screwdriver to push down carefully on
the tab until it locks into the slots on the
bulkhead.
NOTE
The tabs  on the cowl cover will
be damaged if not carefully and completely inserted
into the slots. Consequential damage to the cowl
cover will not be covered under this action.

Install the battery jump post access cover.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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
Install the upper cowl seal .
Install the Tower Brace:

Install the tower brace. Tighten the fasters as
follows:
o
Four nuts <2>, tighten to 30 Nm.
o
Two bolts <3>, tighten to 30 Nm.
o
Two speed-nuts <5>, tighten to 2.5
Nm.
NOTE
The bolts <6> did not require removal. If these
fasteners were removed or loosened during this
operation, secure all other fasteners first, then
tighten the bolts <6> to 30 Nm after all other
fasteners have been torqued to specification.
Install NOx Sensor Module and/or Bracket:

On the driver side strut tower, install the NOx
Sensor 1 Module and/or bracket.
NOTE
Some bracket variation exists between vehicle
models. Photo shown may not match all vehicle
configurations.


Install either the two nuts securing the NOx
Module to the bracket, and/or the two nuts
securing the mounting bracket to chassis
.
o
Tighten the plastic nuts to 2 Nm.
o
Tighten the steel nuts to 7.5 Nm
Connect the electrical connector for the NOx
Sensor 1 Module .
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 67 of 77
Install Engine Cover:

Install the engine cover and carefully press
down in the opposite direction of  one
corner at a time to secure the engine cover into
the retaining pins.
Battery Reconnection:

Open the cover <1> over the battery negative
terminal.

Disconnect the connector <2> from the Battery
Monitoring Control Module -J367- <3>.

Install the battery negative terminal onto the
battery negative post. Tighten the nut <1> to
5 Nm.

Close the battery cover and secure the tabs in
the opposite direction of .
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 68 of 77

If equipped, install and reconnect the electrical
connector for the subwoofer <2>.

Install the dirt tray, if applicable.

Fold back the carpet <1> over the cover.

Install the luggage compartment floor covering
<3>.
Install Lower Exhaust Nut:

Raise the vehicle on the hoist.

Install the remaining “Silver” colored
shouldered hex nut (N 911.308.02) <1> and
tighten to 23 Nm.
Included in installation kit 4H0298099:
Part Number
Part Description
N 911.308.02
Shouldered Hex Nut, selflocking – Silver, exhaust
downpipe flange
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 69 of 77
Install Rear Noise Insulation:

Install the rear noise insulation.

Install the quick release fasteners <4> into the
front noise insulation <3>.

Install the quick release fasteners <2, 7, and
8>.

Install the quick release fasteners <5 and 6>.

Lower vehicle on hoist.
Parts Return / Disposal:
Exhaust Pipe w/ Oxidation Catalyst and Diesel
Particulate Filter:

The Exhaust Pipe w/ Oxidation Catalyst and
Diesel Particulate Filter must be tagged with a
blue zip tie  and returned in order
to be considered for core charge
reimbursement.
All other parts:

Properly store (retain), destroy or dispose of
removed parts in accordance with all state and
local requirements, unless otherwise indicated
and/or requested through the Warranty Parts
Portal (WPP).
Proceed to Section E (Software Update).
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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Section E – For All Criteria (01, 02, 03): Software Update
NOTE
Prior to launching the VAS Diagnostic Tester and starting an update, ensure the following conditions are
met;
The ODIS software is completely up to date.

Refer to the “Alerts” section on ServiceNet home page for the current ODIS version.
The battery charger is connected to the vehicle battery and remains connected for the duration of
the software update.

Battery voltage must remain above 12.5 volts for the duration of the software update. Failure to
do so may cause the update to fail, which could result in damage to the control module. Control
modules damaged by insufficient voltage will not be covered.
The screen saver and power saving settings are off.

Failure to do so may result in the tester entering power save mode during the software update,
which could result in damage to the control module.
The VAS Diagnostic Tester is plugged in using the supplied power adapters.

Under no circumstances should the tester be used on battery power alone during the software
update. Failure to do so may result in the tester powering off during the update, which could
result in damage to the control module.
If using a Bluetooth transmitter head, it is connected to the tester with a USB cable.

Performing a software update using a Bluetooth connection increases the risk of losing
connection during the update, which could result in damage to the control module.
It also greatly increases the time required to perform the update. Requests for additional time
or parts will be denied if the GFF log shows the update was performed using Bluetooth.
The Bluetooth function of the scan tool is physically switched off .
VAS 6150 & VAS 6150A
VAS 6150B
VAS 6150C
(Front panel behind handle)
(Right side behind WIRELESS door)
(Left side behind SC/EX door)
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 71 of 77
WARNING

Radiator Fan(s) may cycle ON high speed during the Update Process! There is a serious risk that personal
injury may result if contact is made with spinning fan blades. Keep hands and all objects away from Radiator
Fan(s) during Update Process!

The wiper arms and/or active rear spoiler (if equipped) WILL operate during this Update Process. Do not
place hands or equipment on any moving parts of the vehicle. There is a serious risk that personal injury or
property damage may result if contact is made with the wiper arms or active rear spoiler (if equipped) during
this Update.
TIP
To Update-Programming using SVM, review and follow instructions in Technical Bulletin 2011732: Software Version
Management (SVM) Operating Instructions.
The SVM Process must be completed in its entirety so the database receives the update confirmation response. A
warranty claim may not be reimbursed if there is no confirmation response to support the claim.

Open the hood.

Access the battery charging posts.

Switch the ignition on.

Apply the parking brake.

Switch off all consumers (headlights, heated
seats, climate control, etc.).

Connect the VAS6150X/VAS6160X Diagnostic
Tester to the vehicle.

Start the ODIS program.

Attach the GRX3000VAS Tester/Charger (or
equivalent) to the vehicle battery charging
posts.
NOTE
Vehicles with Battery Monitoring Control Module
-J367- and/or an EFB Battery:
When connecting the charger to the battery, connect
the positive cable to the positive terminal of the
battery and connect the negative cable to the
grounding lug on the chassis. DO NOT connect the
ground cable directly to negative terminal of the
battery.

Turn the hazards on.
CAUTION
The procedure may cancel itself if the hazard warning
lights are not switched on. The hazard warning lights
prevent the system from switching to bus sleep mode
during the update.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 72 of 77

Confirm that scan tool is communicating with
the diagnostic head by USB cable.
o
If the Bluetooth or WiFi symbol is
shown, then disconnect the diagnostic
head from the vehicle and reconnect
the USB cable to the diagnostic head
and then reattach to the vehicle.

Upon ODIS
.

Select “Self Test” .

Select “Software Version Management”, then
select “SVM Code input” .

Select “Attach to the test plan” .
startup,
select
“Diagnosis”
NOTE
RISK of Scan Tool Damage!
Do not leave the scan tool on the windshield or trunk
deck lid during the flash process, as it is possible that
the windshield wipers and active rear spoiler (if
equipped) may cycle.

From the Test plan screen, Select “SVM Code
input” test plan , then select “Perform
test” .

Follow the on-screen prompts.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 73 of 77
NOTE
Using Bluetooth for this action is PROHIBITED!
Damage caused to electronic components (e.g.
ECM, TCM, etc.) during the SVM update process is
not covered.

Enter the corrective action code (SVM code) as
listed below.
SVM code
23Z8A248

Select “Accept”.

Follow the on-screen prompts.
WARNING

Radiator Fan(s) may cycle ON high speed
during the Update Process! There is a
serious risk that personal injury may result
if contact is made with spinning fan blades.
Keep hands and all objects away from
Radiator Fan(s) during Update Process!

The wiper arms and/or active rear spoiler (if
equipped) WILL operate during this Update
Process! Do not place hands or equipment
on any moving parts of the vehicle. There
is a serious risk that personal injury or
property damage may result if contact is
made with the wiper arms or active rear
spoiler (if equipped) during this Update.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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NOTE
STOP!
There are additional procedures that must be
completed in their entirety before exiting the GFF
Update/Flash Process.

After the GFF Update/Flash Process
completes additional test plan operations will
automatically begin a series of self-checks and
adaptations, including:

o
Oxygen Sensor adaptation reset.
o
Diesel Particulate Filter adaptation
reset.
o
Exhaust Gas Temperature Sensor
rationality check.
o
Oxygen Sensor and NOx Sensor
rationality checks.
You must to follow the on-screen prompts and
cycle the ignition when requested. You must
also start, accelerate, and stop the engine
when requested during this process.

o
Cycle the ignition on and off when
indicated by the on-screen prompts.
Be sure to wait for the progress bar to
complete
any
required
timing
countdowns.
o
You will be required to start the engine
and accelerate to 1,200 RPM’s during
this operation. The “Glow Plug” lamp
will begin to flash and the engine
throttle will be disabled.
This is
normal.
When the Test Plan indicates that all additional
operations have been successfully completed,
continue to the next step.
NOTE
The update may fail if the following pre-requisites are not met:


Hazards not on during flash
Battery voltage too low or insufficient charger used


ODIS version too low
Incorrect diagnostic head used
If the update fails and one of the above pre-requisites was not met:

Additional time to complete the flash due to pre-requisites not being met will not be covered by this campaign.
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 75 of 77

After receiving confirmation that the Flash
operation and additional GFF Test Plan
operations have completed successfully,
select “Send” to send the diagnostic protocol
online.

Follow the on-screen prompts.
TIP
Technicians may find it helpful to also store the log
on a USB stick for back-up.
TIP
When exiting GFF, it is important to select “No”
.

Disconnect the VAS tester.

Reset all customer convenience features (one
touch window operation, radio presets, etc).

Switch off and disconnect the battery charger.

Reinstall the battery cover.

Release the parking brake.

Perform road test.
Proceed to Section F
Section F – Campaign Completion Stamp

Once the campaign has been completed,
the technician should stamp the repair
order.

Stamps are available for ordering through
the Compliance Label Ordering Portal.

Proceed to Section G (Campaign
Completion Label)
Item#: AUD4927ENG
-OR-
Item # AUD4927FRE
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
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23Z8 Page 76 of 77
Section G – Campaign Completion Label
Install Campaign Completion Label

Fill out and affix Campaign Completion Label,
part number CAMP 010 000, next to the
vehicle emission control information label.
TIP
Ensure Campaign Completion Label does not cover
any existing label(s).
Proceed to Section H (Parts
Return/Disposal).
Section H - Parts Return/Disposal
Parts Return / Disposal:
The Exhaust Pipe w/ Oxidation Catalyst and Diesel Particulate Filter:

The Exhaust Pipe w/ Oxidation Catalyst and Diesel Particulate Filter must be tagged with a blue zip tie  and returned in order to be considered for core charge reimbursement.
All other parts:

Properly store (retain), destroy or dispose of removed parts in accordance with all state and local
requirements, unless otherwise indicated and/or requested through the Warranty Parts Portal (WPP).
All Work Complete.
Appendix A – Contents of Installation Kit, part number 4H0.298.099
Installation Kit
4H0.298.099
Part Number
4G0.253.115.A
8W0.253.115.J
N 911.308.01
N 911.308.02
N 909.377.02
Part Description
Gasket, Turbocharger
Gasket, Exhaust Downpipe
Shouldered Hex Nut, self-locking – Turbocharger (Copper)
Shouldered Hex Nut, self-locking – Exhaust Downpipe (Silver)
Tie Strap
Quantity
1
1
3
3
1
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi dealer. 2019 Audi of America, Inc. All Rights Reserved.
August 2019
TDI / AEM-C EMISSIONS SERVICE ACTION
23Z8 Page 77 of 77