ABS sensor causing airbag error?

[milktree]

Is there any reason that a failed or failing ABS wheel speed sensor could cause the airbag light to come on?

I ask because one of my ABS sensors is failing, such that the dash lights are off when I start the car, but once I hit about 50mph the dash lights up with ABS light, then traction control light, then the TPMS light.

Then shortly after that, the airbag light comes on.

The timing suggests the failures are related, but I don't understand how an ABS sensor would ever be related to airbag functionality.

Below (hidden with "spoiler" to avoid clutter) is attached the VCDS error output.

I see a bunch of "Rear Left Wheel Speed Sensor" stuff, which is why I suspect the sensor.

A failing wheel speed sensor would easily explain the ABS, traction control, and TPMS errors. But not airbag.

'course, in an effort to be "clever" I thought I'd swap the rear right and rear left sensors to see if the errors changed, and managed to completely destroy the right rear sensor while trying to remove it, so I'm buying a couple sensors no matter what.


One thing that occurred to me is that it might not be the sensor, but the magnet ring... but I'm committed to replacing the sensors now.

Spoiler

Thursday,14,September,2023,17:52:42:01310
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 23.3.1.0 (x64)
Data version: 20230421 DS346.2
www.Ross-Tech.com


VIN: 3VWFA7AU1FM****** License Plate:
Mileage: 170,335 km 105,841 mi Repair Order:



--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


Chassis Type: AU-VW37 (5Q0)
Scan: 01 03 05 08 09 15 16 17 19 2B 42 44 47 52 5F 75

VIN: 3VWFA7AU1FM504013 Mileage: 170335km-105841miles

01-Engine -- Status: Malfunction 0010
03-ABS Brakes -- Status: Malfunction 0010
15-Airbags -- Status: Malfunction 0010
2B-Steer. Col. Lock -- Status: Malfunction 0010
44-Steering Assist -- Status: Malfunction 0010

-------------------------------------------------------------------------------
Address 01: Engine (J623-CRUA) Labels:. 04L-907-309-V1.clb
Part No SW: 04L 997 022 M HW: 04L 907 309
Component: R4 2.0l TDI H23 9458
Revision: 85H23--- CVN: 500D7A2038D3FF82B866C2AD
Coding: 01190012032410081000
Shop #: WSC 01015 444 00000
ASAM Dataset: EV_ECM20TDI01104L997022M 004002
ROD: EV_ECM20TDI01104L997022N_VW37.rod
VCID: 3A7B6A12BD5A8743C5-806E
VINID: 0E69D64474650567450040010C58400EF4

2 Faults Found:
17158 - Implausible Data Received from ESP Control Module
U0416 00 [032] - -
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 6
Fault Frequency: 2
Mileage: 170272 km
Date: 2023.09.14
Time: 12:14:07

Engine RPM: 1646.50 /min
Normed load value: 54.1 %
Vehicle speed: 98 km/h
Coolant temperature: 91 ∞C
Intake air temperature: 95 ∞C
Ambient air pressure: 1010 mbar
Voltage terminal 30: 13.740 V
Unlearning counter according OBD: 40
Drivetrain coordinator: ACC fault status-Bits 0-7: 0
Drivetrain coordinator: ACC fault status-Bits 0-7: 0
Drivetrain coordinator: brake fault status-Bits 0-7: 4
Drivetrain coordinator: brake function status-Bits 0-7: 0
Drivetrain coordinator: brake function status-Bits 0-7: 0
Acceleration: 0.001 m/s≤

7150 - Implausible Data Received from Steering Angle Sensor Module (G85)
U0428 00 [032] - -
Intermittent - Not Confirmed - Tested Since Memory Clear

Readiness: 0 0 0 0 0

-------------------------------------------------------------------------------
Address 03: ABS Brakes (J104) Labels: 5Q0-907-379-ESP-V1.clb
Part No SW: 3Q0 907 379 P HW: 3Q0 907 379 C
Component: ESC H32 0385
Revision: 00000000 Serial number: 50165000000641
Coding: 04FA6AA1242009700077020181C62520562490004081A4B200630050C002
Shop #: WSC 01383 790 50316
ASAM Dataset: EV_Brake1UDSContiMK100ESP 034033
ROD: EV_Brake1UDSContiMK100ESP_034_VW37.rod
VCID: 479D03E6FEA8EAAB4A-8012

4 Faults Found:
0079 - Rear Left Wheel Speed Sensor
C101C 29 [008] - Signal Implausible
Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 2
Reset counter: 252
Mileage: 170272 km
Date: 2023.09.14
Time: 12:14:08

16389 - TPMS Display
C1146 F1 [009] - Currently Not Available
Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Reset counter: 207
Mileage: 170128 km
Date: 2023.08.31
Time: 15:58:00

16401 - Tire Pressure Warning
C102D 00 [008] - -
Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 3
Reset counter: 172
Mileage: 163761 km
Date: 2023.04.24
Time: 09:52:02

16417 - Display for Tire Pressure Monitoring
C1146 02 [008] - Signal Failure
Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 2
Reset counter: 252
Mileage: 170289 km
Date: 2023.09.14
Time: 12:38:05




-------------------------------------------------------------------------------
Address 15: Airbags (J234) Labels:| 5Q0-959-655.clb
Part No SW: 5Q0 959 655 J HW: 5Q0 959 655 J
Component: AirbagVW20 009 0825
Serial number: 003GCR016BH7 Dataset Number: 5GM003V____ 0037
Coding: 8CCCFC00000000005000001AC24800000065
Shop #: WSC 01383 790 50316
ASAM Dataset: EV_AirbaVW20SMEVW37X 002138
ROD: EV_AirbaVW20SMEVW37X_VW37.rod
VCID: 479D03E6FEA8EAAB4A-8012

Seat occupied recognition passenger side:
Subsystem 1 - Part No SW: 4M0 959 339 B HW: 4M0 959 339 B
Component: BF-Gewichtss. H10 0021
Serial number: IBH0000J150002EU7C07
Coding: 303137

Crash sensor for side airbag: driver side:
Subsystem 2 - Part No SW: ----------- HW: 480 001 501 15
Component: SideSensor_Df 001 0887
Serial number: 3570000000059084F21G
Coding: 2D2D2D

Front Passenger's Side Airbag Crash Sensor:
Subsystem 3 - Part No SW: ----------- HW: 480 001 501 15
Component: SideSensor_Pf 001 0887
Serial number: 3580000000078A50D21J
Coding: 2D2D2D

Rear Side Airbag Crash Sensor (on driver's side):
Subsystem 4 - Part No SW: ----------- HW: 480 401 501 15
Component: SideSensor_Dr 001 6149
Serial number: 3510002C5196FF427045
Coding: 2D2D2D

Passenger side rear thorax airbag crash sensor:
Subsystem 5 - Part No SW: ----------- HW: 480 401 501 15
Component: SideSensor_Pr 001 6149
Serial number: 3520002C5196FF45A15E
Coding: 2D2D2D

Crash sensor for front airbag: driver side:
Subsystem 6 - Part No SW: ----------- HW: 480 402 101 15
Component: FrontSensor_D 001 6149
Serial number: 3550002AD19121A2717-
Coding: 2D2D2D

Crash sensor for front airbag: front passenger side:
Subsystem 7 - Part No SW: ----------- HW: 480 402 101 15
Component: FrontSensor_P 001 6149
Serial number: 3560002A719121A1923T
Coding: 2D2D2D

1 Fault Found:
9483008 - Seat Occupied Recognition
B10B3 00 [008] - Function Restriction due to Implausible Message(s)
Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 4
Reset counter: 252
Mileage: 170273 km
Date: 2023.09.14
Time: 12:14:23



-------------------------------------------------------------------------------
Address 2B: Steer. Col. Lock (J764) Labels:* 5Q0-905-861.clb
Part No SW: 5Q0 905 861 A HW: 5Q0 905 861 A
Component: ELV-MQBA H01 0120
Revision: 00000000 Serial number: 15000006490003
Coding: 5500000000000000
Shop #: WSC 00066 790 07030
ASAM Dataset: EV_ELVMarquMQB 004111
ROD: EV_ELVMarquMQB_004_VW37.rod
VCID: 3467442A9F3E71331F-8060

2 Faults Found:
13893632 - Function Restricted due to Insufficient Voltage
U1400 00 [008] - -
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 6
Fault Frequency: 1
Reset counter: 251
Mileage: 170245 km
Date: 2023.09.14
Time: 11:37:16

ELV State: 24
Information Clamps: 77 64
CoCo State: A0 01
WFS State: 17 0E
Vehicle speed: 0.00 km/h
Voltage: 3D
AD-Value H-bridge: 1D
Clamp15 flip flop: SSTx: button contacts: 06
CAN signals: 00

13637378 - Databus
U1123 00 [008] - Received Error Message
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 6
Fault Frequency: 2
Reset counter: 252
Mileage: 170272 km
Date: 2023.09.14
Time: 12:14:07

ELV State: 04
Information Clamps: 77 60
CoCo State: E0 01
WFS State: 1F 06
Vehicle speed: 92.22 km/h
Voltage: 78
AD-Value H-bridge: 3B
Clamp15 flip flop: SSTx: button contacts: 06
CAN signals: 00



-------------------------------------------------------------------------------
Address 44: Steering Assist (J500) Labels:| 5Q0-909-144.clb
Part No SW: 5Q0 909 144 R HW: 5Q0 909 144 R
Component: EPS_MQB_ZFLS 126 1061
Dataset Number: 5GM074V____ 0515
Coding: 0102
Shop #: WSC 00066 790 00221
ASAM Dataset: EV_SteerAssisMQB 012140
ROD: EV_SteerAssisMQB_012_VW37.rod
VCID: 438517F6CA90C68B96-8016

2 Faults Found:

20228 - Databus
U1123 00 [008] - Received Error Message
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 6
Reset counter: 252
Mileage: 170272 km
Date: 2023.09.14
Time: 12:14:08

Motor status: 02
System status: Driving mode
Supply voltage: 13.75 V
Temperature: 52.0 ∞C
KFC: 4F
KFA: 00 04
Freeze frame conditions: 21
uAdSensI_U1V2Filtered_gdu16: 1.20 V
uAdSensI_U5VFiltered_xdu16: 0.00000 V
uioUdNotFilt_xdu16: 13.73 V
uAdSensI_SwitchedKl30_xdu16: 13.76 V
ASC_CTRL_GET_ILWS_ERR_FLAGS: 00

19716 - Databus
U1123 00 [008] - Received Error Message
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 6
Reset counter: 252
Mileage: 170272 km
Date: 2023.09.14
Time: 12:14:08

Motor status: 02
System status: Driving mode
Supply voltage: 13.75 V
Temperature: 52.0 ∞C
KFC: 4D
KFA: 00 04
Freeze frame conditions: 21
uAdSensI_U1V2Filtered_gdu16: 1.20 V
uAdSensI_U5VFiltered_xdu16: 0.00000 V
uioUdNotFilt_xdu16: 13.89 V
uAdSensI_SwitchedKl30_xdu16: 13.91 V
ASC_CTRL_GET_ILWS_ERR_FLAGS: 00


End-------------------------(Elapsed Time: 04:31)--------------------------

 

[JELLOWSUBMARINE]

Clock spring?

 

[milktree]

Clock spring?

I don't think so, because of the constant "rear left sensor" stuff. Clock spring would make the airbag light come on, but not the other stuff. And it wouldn't come on only after the other stuff. And the rest of the buttons on the wheel work (that I've tested. I haven't tried the horn)

 

[JELLOWSUBMARINE]

Maybe. The mk6 anyway had a big warrentee extension on them. They do weird things??

 

[Nuje]

I think there's a recall out on the passenger seat detection switch (PODS: passenger occupancy detection system) - the thing that's throwing the airbag light. At least there is/was on our A3 e-tron - which is an MQB car as well and shares a lot of the same subsystems.

Now, why it would occur only after the ABS sensor series of cascading errors.... ¯\_(ツ)_/¯

 

[740GLE]

So you have codes for a failed wheel speed sensor? But you don't want to replace it?

What are the codes for the airbag? They should be linked to vehicle speed detection.

The airbags errors should also be linked to the ECU/ABS not knowing proper speed thus can't properly deploy the air bags in a safe manor. Call it double/quad redundancy of the ABS/Airbag system, but the number of times airbags went off when they shouldn't have outweighs logic of reducing inputs to the airbag systems.

 

[milktree]

So you have codes for a failed wheel speed sensor? But you don't want to replace it?

What did I say that makes you think I don't want to replace it?

What are the codes for the airbag? They should be linked to vehicle speed detection.

All the codes are in the "spoiler" in post #1.

I'm not claiming I know how to read them.

The airbags errors should also be linked to the ECU/ABS not knowing proper speed thus can't properly deploy the air bags in a safe manor. Call it double/quad redundancy of the ABS/Airbag system, but the number of times airbags went off when they shouldn't have outweighs logic of reducing inputs to the airbag systems.

That makes a lot of sense. It suggests that once I get the replacement sensors in the airbag errors should go away.

I'm surprised that the airbag system requires *all* the wheel sensors to be working safely. I'd have thought any three, or even two would be sufficient. Especially when combined to the transmission speed sensor.

 

[Nuje]

I've had an ABS sensor go bad on my mk7 and don't recall having airbag lights/faults along with it.
(But then again....if I don't write things down these days.... ¯\_(ツ)_/¯ ; and even when I do write things down, I'll still sometimes question my notes. e.g. "Did I *really* flush the brake fluid last January....I don't remember doing that at all". )

 

[740GLE]

I've had an ABS sensor go bad on my mk7 and don't recall having airbag lights/faults along with it.
(But then again....if I don't write things down these days.... ¯\_(ツ)_/¯ ; and even when I do write things down, I'll still sometimes question my notes. e.g. "Did I *really* flush the brake fluid last January....I don't remember doing that at all". )

How stock is your ABS controller in coding these days

might have tweaked a bit or byte here or there

 

[740GLE]

What did I say that makes you think I don't want to replace it?

All the codes are in the "spoiler" in post #1.

I'm not claiming I know how to read them.

That makes a lot of sense. It suggests that once I get the replacement sensors in the airbag errors should go away.

I'm surprised that the airbag system requires *all* the wheel sensors to be working safely. I'd have thought any three, or even two would be sufficient. Especially when combined to the transmission speed sensor.

Ah never seen the spoiler used for codes, handy to high all the noise of a VCSD data dump.

Did you clear the Air bag seat sensor fault and did it come back?

Any moisture recently on the seat?

 

[milktree]

Ah never seen the spoiler used for codes, handy to high all the noise of a VCSD data dump.

Ah! That explains that. The VCDS dump was big and bulky, so I figured I'd make it ... less cumbersome.

Did you clear the Air bag seat sensor fault and did it come back?

Any moisture recently on the seat?

I have not cleared the codes yet, so I don't have good (any) data there.

There has not been any moisture on the seat.

The light is still on though, and since I destroyed one of the ABS sensors while trying to swap the left and right it does not even wait for the car to start moving before coming on when I start the car.


The new ABS sensors are showing up tomorrow, I'll install them and report back.

 

[740GLE]

yeah air bags are hard coded that stay on the dash even for intermittent issues unless you clear the codes.

On our Alltrack the passenger seat sensor did fail within a year of ownership, no water, no dog claws (70lbs pitbull) so the dealer was able to warranty the full seat cover repair.

 

[Nuje]

How stock is your ABS controller in coding these days
might have tweaked a bit or byte here or there

Haha! Valid point, my friend!
And to that very point, I'm also not using stock ABS sensors on the rear wheels (adaptive cruise control requires different sensor). And those aftermarket ones are still going just fine (hoping he doesn't jinx it). At $20/pr and them being easy slide-in/out (compared to the Mk4 abomination), I have a few extra on-hand if/when one does go bad.