2053492.4

Technical Service Bulletin
Topic
Market area
Brand
Transaction No.
Level
Status
Release date
Air spring fault finding
Bentley: worldwide (2WBE)
Bentley
2053492/4
EH
Released for publishing
May 17, 2019
New customer code
Object of complaint
chassis -> damping\suspension regulation -> automatic damper adjustment
chassis -> level control system, pitch and roll compensation
chassis -> damping\suspension regulation -> automatic level control system
Complaint type
Position
functionality -> no function
functionality
functionality -> no function
Vehicle data
Mulsanne
Sales types
Type
3Y2*
3Y2*
3Y2*
3Y2*
3Y2*
3Y2*
3Y2*
3Y2*
3Y2*
3Y2*
3Y6*
3Y6*
3Y6*
3Y6*
MY
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2017
2018
2019
2020
Brand Designation Engine code Gearbox code
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
Final drive code
*
*
*
*
*
*
*
*
*
*
*
*
*
*
Continental Series and Flying Spur
Sales types
Type
39*
39*
39*
39*
39*
39*
39*
39*
3W*
3W*
3W*
3W*
3W*
3W*
3W*
3W*
3W*
3W*
MY
2012
2013
2014
2015
2016
2017
2018
2019
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
Brand Designation Engine code Gearbox code
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
E
*
*
Final drive code
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
4W*
4W*
4W*
4W*
4W*
4W*
2014
2015
2016
2017
2018
2019
E
E
E
E
E
E
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
New Continental GT
Sales types
Type
3S3*
3S3*
3S3*
MY
2018
2019
2020
Brand Designation Engine code Gearbox code
E
*
*
E
*
*
E
*
*
Final drive code
*
*
*
Bentayga
Sales types
Type
4V1*
4V1*
4V1*
4V1*
MY
2017
2018
2019
2020
Brand Designation Engine code Gearbox code
E
*
*
E
*
*
E
*
*
E
*
*
Final drive code
*
*
*
*
New Continental GTC
Sales types
Type MY Brand Designation Engine code Gearbox code Final drive code
3S4* 2019 E
*
*
*
3S4* 2020 E
*
*
*
Documents
Document name
master.xml
Technical Service Bulletin
Air spring fault finding
Transaction No.: 2053492/4
Release date: May 17, 2019
Condition
The front and/or rear suspension appears to have dropped.
Technical Background
The list of Bentley vehicles below are fitted with air springs as part of the suspension system. Should air leak from the air springs, this will cause the
suspension to drop. However, the dropping of the suspension does not necessarily mean that the air spring is faulty.
The “Measure” section of this TPI describes how and where to check for air leaks on the front and rear air springs, the air pump compressor, pipes,
valve unit and air reservoirs. This includes potential air leak points on the air springs and also the locations of an air leak that can be repaired without
the need to replace an air spring.
These checks should be carried out in conjunction with the Elsapro procedure “Air suspension – To check” with the use of the special
tool “Air suspension leak tester VAS 751 001” shown in the image below as item (1). Refer to Elsapro, Repair Group 43, “Air
suspension – To check”.
Please follow and complete the check list within the “Measure” section of this TPI to help in diagnosing the issue (the check list does not need to be
sent as an attachment should a DISS technical query be raised).
Should a leak be found from an air spring, compressor, valve unit or reservoir, please raise a DISS technical query and include as much information as
possible including photograph/s of the leak/s location. Once the DISS ticket has been submitted please await clarification from your TSC before
commencing with replacing any of the suspected faulty air springs.
Mandatory reporting is applicable for all air spring related issues.
Production Solution
Not applicable
Service
Reference chart
Please use this generic “Reference Chart” in conjunction with the customer description of the fault and the “Standard Ambient Conditions” of the
DTC's if present, to focus on the relevant area (ie: if a DTC is pointing out to the accumulator and the event data from the DTC and the customer
description explains that the issue appear while the vehicle was driving, then the potential source of the leak well might be in between reservoir, valve
unit or compressor as these three components are active in these particular conditions).
Component
Description
1-5
Solenoid valves
6&7
Front axle suspension struts
8&9
Rear axle suspension units
10
Pressure accumulator
11
Pressure sensor
12
Pressure reading
13
Electrical activation of solenoid valves
14
Compressor connection
Procedure
Position the vehicle on a flat and level surface and allow it to cool down.
•
Important: Set the vehicle suspension into “Jack” mode.
Adhere strips of masking tape (1) from the centre of each wheel to the highest part of the wheel arch as shown, making sure they are applied taut.
Using a tape measure (2), also measure and take note of the ride heights (A-A) at all four corners of the vehicle. See Figure 1.
Figure 1
Leave the vehicle overnight and again measure the ride heights (A-A) at all four corners of the vehicle. Compare these values with those taken
previously.
If there is NO difference in ride heights, and the strips of masking tape are still ‘taut’ then no air leak is present. Please explain to the customer the long
term storage or changing climate conditions would cause a drop in ride height which is normal. As soon as the vehicle is started, the compressor will
level the vehicle automatically. No further action is required.
If there IS a difference in ride heights, and the strips of masking tape (1) have ‘sagged’ (shown in Figure 2), then refer to the following leak finding
procedures below.
Figure 2
It should be noted that if these checks involve a claim through warranty then photographic evidence of the vehicle sagging and air
leak should be included.
Always select “Jack mode” before raising the vehicle and exhausting the air from the suspension system. Refer to Elsapro. Repair
Group 43.
Section 1 - Front suspension air spring fault finding
Before any other checks are made to the front air springs check to confirm the pipes are fully inserted and firmly connected within
the brass fitting.
Air leakage may not be audible. A possible symptom of air leakage is excessive operation of the air pump located above the rear
diffuser. If no air leakage is apparent at the pipe unions and there is excessive operation of the air pump compressor, there may be a
damaged air supply pipe to an air spring.
With the air suspension fully charged, use leak detector spray or a mild soap solution to check the connections for leaks as shown in the
accompanying table.
Place an X in the appropriate column next to each check.
Front air spring check points - Continental series (pre 2018) and Flying Spur
Check
Yes
No
Comments
Brass fitting to air spring (1)
Brass intermediate connection (2)
Air feed pipe connection (3)
Top of air spring (4)
Air spring gaiter condition (5)
Air canister and canister to air spring (6 & 7)
Bottom of the air spring (8)
Top of the air spring (9). Within engine compartment, pull dust
seal back to inspect!
Front air spring check points – Mulsanne
Check
Air connection to air spring (1)
Upper air spring (2)
Top of air spring (3)
Air spring gaiter condition (4)
Bottom of the air spring (5)
Yes
No
Comments
Front air spring check points – Bentayga
Check
Yes
No
Comments
Air connection to air spring (1)
Top of air spring (2 & 3)
Upper areas of air spring gaiter (4 & 6)
Air spring upper gaiter condition (5)
Lower areas of air spring gaiter (7 & 9)
Air spring upper gaiter condition (8)
Front air spring check points – New Continental GT
Check
Air connection to air spring (1)
Sealing area of top nut (2)
Top crimp area (3)
Top of air spring (4)
Yes
No
Comments
Air spring gaiter condition (5)
Lower areas of air spring gaiter (6)
Switching valves, solenoids and welds (7&8)
Section 2 - Rear suspension air spring fault finding
Before any other checks are made to the rear air springs check to confirm the pipes are fully inserted and firmly connected within the
brass fitting.
Air leakage may not be audible. A possible symptom of air leakage is excessive operation of the air pump located above the rear
diffuser. If no air leakage is apparent at the pipe unions and there is excessive operation of the air pump compressor, there may be a
damaged air supply pipe to an air spring.
With the air suspension fully charged, use leak detector spray or a mild soap solution to check the connections for leaks as shown in the
accompanying table.
Place an X in the appropriate column next to each check.
Rear air spring check points - Continental series (pre 2018) and Flying Spur
Check
Brass fitting to air spring (1)
Top of air spring (2 & 3)
Air spring bellows (4)
Air feed pipe connection (5)
Air spring gaiter condition (6)
Air canister and canister to air spring (7, 8 & 9)
Electrical cable route for air escaping (10)
Yes
No
Comments
Rear air spring check points – Mulsanne
Check
Yes
No
Comments
Air feed pipe connection (1)
Top of air spring (2 & 3)
Upper air spring bellows (4 & 5)
Lower air spring bellows (6 & 7)
Air spring gaiter condition (8 & 9)
Rear air spring check points – Bentayga
Check
Air feed pipe connection (1)
Top of air spring (2)
Air spring gaiter condition (3 & 4)
Lower areas of air spring (5 & 6)
Yes
No
Comments
Rear air spring check points – New Continental GT
Check
Yes
No
Air feed pipe connection (1)
Top of air spring (2)
Air spring gaiter condition (3 & 4)
Lower area of air spring (5)
Section 3 - Air supply unit check points
Check for any air leaks on or around the air supply (compressor) unit.
Place an X in the appropriate column next to each check.
Air supply check points - Continental series (pre 2018) and Flying Spur
Check
Air pipe connections (1 to 6)
Yes
No
Comments
Comments
Air supply check points - Mulsanne
Check
Yes
No
Comments
Air pipe connections (1 to 6)
Air supply check points – Bentayga
Check
Yes
No
Comments
Air pipe connections (arrows)
Air supply check points – New Continental GT
Check
Air pipe connections (2 & 3)
Yes
No
Comments
Section 4 - Air reservoir unit check points
Check for any air leaks on or around the air reservoir.
Place an X in the appropriate column next to each check.
Air supply check points - Continental series (pre 2018) and Flying Spur
Check
Yes
No
Comments
Air pipe connection (arrow)
Location - GT & Flying Spur: LH rear wheel arch
Location – GTC: Behind backboard trim panel
Air supply check points - Mulsanne
Check
Yes
No
Comments
Air pipe connection (arrow)
Location – Boot floor
Air supply check points - Bentayga
Check
Air pipe connections on the twin tanks (arrows)
Location – Rear footwells beneath carpets
Yes
No
Comments
Air supply check points – New Continental GT
Check
Yes
No
Comments
Air pipe connection (2)
Location – Underside of boot floor
Section 5 - Air pipe repairs
If no evident air leak has been detected in the previous sections, refer to Elsapro, Repair Group 43, “Air suspension – To check”.
The “Air suspension leak tester VAS 751 001” is used to check the air spring struts, solenoid valve block, accumulators, compressors, air reservoirs
and air pipes for leaks.
In the event of an air leak from the air pipe/brass fittings on the supply unit the brass fittings and internal olive can be replaced
individually.
To repair an air pipe, refer to Elsapro, “Air Supply Pipe - To Repair” - Repair Group 43.
Using a “Vehicle Tester”, recharge the air system. Refer to Elsapro, “To discharge and charge” - Repair Groups 40 and 42.
Warranty
It should be noted that if checks involve a claim through warranty then photographic evidence of the vehicle sagging and air leak should be included
with the DISS technical query where possible.
Pictures should include the following:
•
Tape (1) applied before and after, showing the tape sagging. See Figure 3.
•
All ride height measurements (A-A) before and after. See Figure 3.
•
Soap solution bubbling at the point of air leak (where possible).
Figure 3