122-E3W4E-10

Service
Technical Information
125/18 ENU
3
3975
Eliminating Transmission Symptoms - Yellow Warning Message "Rear differential lock
failure Adapted driving permitted" in the Instrument Cluster (I-no. GH3): Re-programming
control unit for rear-differential lock (SY 125/18)
Model Line:
Cayenne (9YA)
Model Year:
As of 2018
Equipment:
PTV Plus (controlled rear-differential lock) (I-no. GH3)
Subject:
Rear-differential lock control unit
Symptom:
The yellow warning message "Rear differential lock failure Adapted driving permitted" can appear in the
instrument cluster.
Cause:
The yellow warning message can appear in the instrument cluster due to defective control unit software.
Remedial
Action:
In the event of a customer complaint, if software version "1306" is installed and if the entry "C12B596"
is stored in the fault memory of the rear-differential lock control unit, re-program rear-differential lock
control unit.
Tools:
•
•
9900 - PIWIS Tester 3 with software version 37.400.010 (or higher) installed
Battery charger with a current rating of at least 90 A.
NOTICE
Voltage drop
•
Risk of irreparable damage to control unit
•
Risk of damage to control unit
•
Fault entries in the control unit
•
Coding in the control unit is aborted
•
Malfunctions in control unit, even during programming

Before disconnecting the control unit, switch off ignition and remove ignition key.

Make sure that the power supply is not interrupted during programming.

Connect battery charger/power supply - Suitable for AGM Type batteries, recommended current
rating of 90A fixed voltage 13.5V to 14.5V.
AfterSales
Sep 7, 2018
Page 1 of 4
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Service
3975
ENU
Work Procedure:
1
Technical Information
125/18
Preliminary work:
1.1
Connect a battery charger with a current rating of at least 90 A.
1.2
Switch on the ignition using the original driver's key. On vehicles with “Porsche Entry &
Drive”, do this by replacing the control unit in the ignition lock with the original driver's key if
necessary.
NOTICE
Coding will be aborted if the WLAN connection is unstable.
•
An unstable WLAN connection can interrupt communication between PIWIS Tester 3 and the
vehicle communication module (VCI). As a result, coding/programming may be aborted.

During control unit coding/programming, always connect PIWIS Tester 3 to the vehicle
communication module (VCI) via the USB cable.
1.3
9900 - PIWIS Tester 3 with software version 37.400.010 (or higher) installed must be
connected to the vehicle communication module (VCI) via the USB cable. Then, connect the
communication module to the vehicle and switch on the PIWIS Tester.
1.4
On the PIWIS Tester start screen, call up the  'Diagnostics' menu.
The diagnostic application is then started and the control unit selection screen is populated.
Information
The procedure described here is based on the 9900 - PIWIS Tester 3 software version
37.400.010.
The PIWIS Tester instructions take precedence and in the event of a discrepancy, these are the
instructions that must be followed.
A discrepancy may arise with later software versions for example.
2
"Rear-differential lock" control unit  re-program:
Menu
•
Control
unit/Function
Control units
’Overview’
2.2
 Follow instructions:
Action

Instructions/information or
2.1
•
•
Sep 7, 2018
Page 2 of 4

'Additional menu'
•
confirm/execute
 Result/consequence of action
call up
Create Vehicle Analysis Log (VAL) if necessary and
carry out any campaigns that are available for the vehicle.
AfterSales

•F7“
•Yes“/•No“/
•F12“
Service
Technical Information
2.3
Campaign
number
2.4
125/18 ENU
3975
‘Campaign’
select
•F12“
Value:
’H4Y8Z’
enter
•F12“
3
Read and follow the information and instructions on the PIWIS Tester during the guided
programming sequence. Then press •>>“ to continue.
During the programming sequence, the control unit is re-programmed and then re-coded automatically if necessary.
Do not interrupt programming and coding.
Once control unit programming - and coding if necessary - is complete, you will be prompted to
switch the ignition off and then back on again after a specified waiting time.
2.5
Control units
’Overview’
2.6
'Extended
identifications'
select
Software version programmed during this
campaign
1405
Transverse lock
select
•F12“
If programming is not completed successfully (error message “Programming unsuccessful”),
programming must be repeated.
2.7
3
Maintenance/
repairs
Commissioning
select
•F12“
Subsequent work:
3.1
Read out and erase all fault memories.
Information
If there are still fault memory entries in individual control units, start the engine briefly and
then switch it off again. Wait for approx. 10 seconds before switching the ignition on again
and re-establish the connection between the PIWIS Tester and the vehicle. Then read out and
erase the fault memories of the affected control units again separately.
3.2
Switch off ignition.
3.3
Disconnect the PIWIS Tester from the vehicle.
3.4
For vehicles with Porsche "Entry & Drive", replace the original vehicle key in the ignition lock
with the control panel again.
3.5
Switch off and disconnect the battery charger.
End of action required.
AfterSales
Sep 7, 2018
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Service
3975
Invoicing:
ENU
Technical Information
125/18
The work involved is invoiced under the labor operation:
I No.
APOS
Labor operation
39752550
Programming control unit for rear-differential lock
For invoicing and documentation using PQIS, enter the following coding:
Location (FES5)
39750
Rear-differential lock control unit
Damage type (SA4)
4045
Warning activated
Important Notice: Technical Bulletins issued by Porsche Cars North America, Inc. are intended only for use by professional automotive technicians who have attended Porsche service training
courses. They are written to inform those technicians of conditions that may occur on some Porsche vehicles, or to provide information that could assist in the proper servicing of a vehicle. Porsche special
tools may be necessary in order to perform certain operations identified in these bulletins. Use of tools and procedures other than those Porsche recommends in these bulletins may be detrimental to the
safe operation of your vehicle, and may endanger the people working on it. Properly trained Porsche technicians have the equipment, tools, safety instructions, and know-how to do the job properly and
safely. Part numbers listed in these bulletins are for reference only. The work procedures updated electronically in the Porsche PIWIS diagnostic and testing device take precedence and, in the event of a
discrepancy, the work procedures in the PIWIS Tester are the ones that must be followed.
© 2018 Porsche Cars North America, Inc.
Sep 7, 2018
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AfterSales