Electrical issues

[Stianha]

Hello
I have a 2011 Audi A8 B8 that I have some electrical problems that I'm having a hard time figuring out. Issues are:
- Front window wiper not working
- Driving light issues: driving lights work, but can't turn them off, the switch have to be in 0 or on position, if in park or Auto, I get a "lights are on" warning when turning ignition off. I also can't turn the driving lights off, or turn it to parking lights, and left high beam doesn't work. There is also a fault code for the switch having an implausible signal, this fault code is the same even if I dissconnect the switch.
- No cold air from A/C
- No backlight in most of the switches, instruments and MMI screen
When turning on the ignition I get a "vehicle lights fault" warning.

When I first got these problems, they only happened sometimes when starting the car, and shutting it off would temporary fix it, it is now permanent.
I have checked all the fuses I can find, but none were bad. I have checked the J519 control unit, I did some googling and some had water damage in this control unit that caused some problems, but mine looked fine. Can this still be the problem even if it looks ok?

Also when I run a ful scan with VCDS I get a warning for a second or two in saying something like "stabilisation program fault".
I will post the fault code scan in a comment.

Any help would be appreciated.

[Stianha]

Chassis Type: 8K-AU48 (8T0)
Scan: 01 03 05 08 09 0F 10 15 16 17 19 20 42 46 52 53 55 56 5F 62
          69 6D 72

Mileage: 135910km-84450miles

01-Engine -- Status: OK 0000
03-ABS Brakes -- Status: OK 0000
04-Steering Angle -- Status: OK 0000
05-Acc/Start Auth. -- Status: Malfunction 0010
08-Auto HVAC -- Status: OK 0000
09-Cent. Elect. -- Status: Malfunction 0010
0F-Digital Radio -- Status: Not registered 0001
10-Park/Steer Assist -- Status: OK 0000
15-Airbags -- Status: OK 0000
16-Steering wheel -- Status: OK 0000
17-Instruments -- Status: OK 0000
19-CAN Gateway -- Status: Malfunction 0010
20-High Beam Assist. -- Status: OK 0000
42-Door Elect, Driver -- Status: OK 0000
46-Central Conv. -- Status: Malfunction 0010
52-Door Elect, Pass. -- Status: OK 0000
53-Parking Brake -- Status: OK 0000
55-Headlight Range -- Status: OK 0000
56-Radio -- Status: OK 0000
5F-Information Electr. -- Status: OK 0000
62-Door, Rear Left -- Status: OK 0000
69-Trailer -- Status: OK 0000
6D-Trunk Elect. -- Status: OK 0000
72-Door, Rear Right -- Status: OK 0000
-------------------------------------------------------------------------------
Address 01: Engine (J623-CAGA)       Labels:. 03L-906-019-CAG.clb
   Part No SW: 03L 906 022 RL    HW: 03L 906 019 AL
   Component: R4 2.0l TDI   H35 9978  
   Revision: 25H35---    CVN: DC8C8AE7
   Coding: 12194012243601080000
   Shop #: WSC 45503 002 1048576
   ASAM Dataset: EV_ECM20TDI03L906022RL A02009
   ROD: EV_ECM20TDI03L906019AL.rod
   VCID: 00598250CA87E09A0FB-8054
   VINID: 9D196AAAA21B0534401C00851020EB5028

No fault code found.
Readiness: 0 0 0 0 1 

-------------------------------------------------------------------------------
Address 03: ABS Brakes (J104)       Labels:. 8K0-907-379-V1.clb
   Part No SW: 8K0 907 379 BG    HW: 8K0 907 379 BG
   Component: ESP8 quattro  H04 0020  
   Revision: --------    Serial number: --------------
   Coding: 188504
   Shop #: WSC 06334 000 00000
   VCID: 7F5B01ACB7F99F62761-802A

No fault code found.

-------------------------------------------------------------------------------
Address 05: Acc/Start Auth. (J393)       Labels:. 8K0-907-064-05.clb
   Part No SW: 8K0 907 064 CQ    HW: 8K0 907 064 CQ
   Component: BCM2 2.0      H05 0435  
   Revision: 00002001    
   Coding: 032200
   Shop #: WSC 06335 000 00000
   VCID: 015F8754C10DE992005-8054

   Subsystem 1 - Part No SW: 8T0 959 754 D    HW: 8T0 959 754 D
   Component: FBSAUDIB8 IDG  H60 0072 
   Serial number: 0511000052815021    

   Subsystem 2 - Part No SW: 8K0 905 852 D    HW: 8K0 905 852 D
   Component: J764 ELV MLB  H37 0042 
   Serial number: 2311000206770002    

1 Fault Found:
01330 - Central Control Module for Central Convenience (J393) 
            013 - Check DTC Memory
             Freeze Frame:
                    Fault Status: 01101101
                    Fault Priority: 6
                    Fault Frequency: 2
                    Reset counter: 9
                    Mileage: 135917 km
                    Time Indication: 0
                    Date: 2023.07.30
                    Time: 15:35:20


-------------------------------------------------------------------------------
Address 08: Auto HVAC (J255)       Labels: Redir Fail!
   Part No SW: 8T1 820 043 AH    HW: 8T1 820 043 AH
   Component: KLIMA 1 ZONE  H08 0182  
   Revision: A1000000    Serial number: 01240920110777
   Coding: 34300000
   Shop #: WSC 45503 002 1048576
   VCID: 77ABE98C9FC9A7223E1-8022

No fault code found.

-------------------------------------------------------------------------------
Address 09: Cent. Elect. (J519)       Labels:. 8K0-907-063.clb
   Part No SW: 8K0 907 063 P    HW: 8K0 907 063 P
   Component: BCM1 1.0      H30 0392  
   Revision: 10030001    Serial number: 00000001060469
   Coding: 2600DC914174AF010001000300001D0D0F1C270806010101000000
   Shop #: WSC 06335 123 12345
   VCID: 3C2136A0E66F447A133-8068

2 Faults Found:
02071 - Local Databus 
            012 - Electrical Fault in Circuit
             Freeze Frame:
                    Fault Status: 01101100
                    Fault Priority: 2
                    Fault Frequency: 1
                    Reset counter: 9
                    Mileage: 135917 km
                    Time Indication: 0
                    Date: 2023.07.30
                    Time: 15:35:00

03280 - Switch Position of Light-Switch Knob 
            008 - Implausible Signal
             Freeze Frame:
                    Fault Status: 01101000
                    Fault Priority: 3
                    Fault Frequency: 1
                    Reset counter: 9
                    Mileage: 135917 km
                    Time Indication: 0
                    Date: 2023.07.30
                    Time: 15:35:00


-------------------------------------------------------------------------------
Address 0F: Digital Radio        Labels: None
   Part No SW: KUFATEC DAB+    HW: KUFATEC DAB+
   Component:    
   Revision: 00000000    Serial number: 00000000000000
   Shop #: WSC 00666 142 74100
   VCID: 75B7E38489C5D5322CD-8020

No fault code found.

-------------------------------------------------------------------------------
Address 10: Park/Steer Assist (J446)       Labels:. 8K0-919-475.clb
   Part No SW: 8K0 919 475 T    HW: 8P0 919 475 M
   Component: PARKHILFE 4K  H01 0081  
   Revision: 11001001    Serial number: 36861126200121
   Coding: 010003
   Shop #: WSC 06335 000 00000
   VCID: 4ACD6078BCBBEACA91F-801E

No fault code found.

-------------------------------------------------------------------------------
Address 15: Airbags (J234)       Labels:| 8K0-959-655.clb
   Part No SW: 8K0 959 655 L    HW: 8K0 959 655 L
   Component: AirbagVW-AU10 H44 0610  
   Serial number: 003JMD0GGLJ0   Dataset Number: 8K0909602K  0003
   Coding: 30513435363030303030554A304C384B3053
   Shop #: WSC 06335 000 00000
   ASAM Dataset: EV_AirbaECUVWAUDI010 003010
   ROD: EV_AirbaECUVWAUDI010_003_AU48.rod
   VCID: 46D55448A8230EAA757-8012

   Crash sensor for side airbag: driver side: 
   Serial number: 6334MSME6455115FF

   Front Passenger's Side Airbag Crash Sensor: 
   Serial number: 6344MSME65103A7EK

   Rear Side Airbag Crash Sensor (on driver's side): 
   Serial number: 6352QSME685D4D56.

   Passenger side rear thorax airbag crash sensor: 
   Serial number: 6362QSME5D5E4B5C4

   Crash sensor for front airbag: driver side: 
   Serial number: 63732SME295F484CF

   Crash sensor for front airbag: front passenger side: 
   Serial number: 63832SME2D5F4C60E

No fault code found.

-------------------------------------------------------------------------------
Address 16: Steering wheel (J527)       Labels:. 8K0-953-568.clb
   Part No SW: 8R0 953 568 K    HW: 8R0 953 568 K
   Component: Lenks.Modul   H07 0156  
   Revision: 00000000    Serial number: 20110926000987
   Coding: 000017
   Shop #: WSC 06335 000 00000
   VCID: 49CF5F74B9BDE1D2985-801C

   Component: E221 - MFL  H02 0010 

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments (J285)       Labels:. 8T0-920-xxx-17.clb
   Part No SW: 8K0 920 930 N    HW: 8K0 920 930 N
   Component: KOMBIINSTR.   H31 0258  
   Revision: 00000000    Serial number: EJC320P9C     
   Coding: 0F04110002000008010000
   Shop #: WSC 06335 000 00000
   VCID: 38292AB0D257685AF7B-806C

No fault code found.

-------------------------------------------------------------------------------
Address 19: CAN Gateway (J533)       Labels:. 8T0-907-468.clb
   Part No SW: 8T0 907 468 AE    HW: 8T0 907 468 L
   Component: GW-BEM 5CAN-M H10 0117  
   Revision: FC100058    Serial number: 5800F11905011A
   Coding: 00CF07
   Shop #: WSC 06335 000 00000
   VCID: 04518E40DE1FFCBA2B3-8050

   Subsystem 1 - Part No SW: 8X0 915 181     HW: 8X0 915 181 
   Component: J367-BDM  H07 0140 
   Serial number: 00000000005650487059

   Subsystem 2 - Part No SW: 8K0 959 663     HW: 8K0 959 663 
   Component: J532_DCDCStab  H17 0042 
   Serial number: 11265001789021200181

1 Fault Found:
01044 - Control Module Incorrectly Coded 
            000 - -
             Freeze Frame:
                    Fault Status: 01100000
                    Fault Priority: 1
                    Fault Frequency: 1
                    Reset counter: 9
                    Mileage: 135917 km
                    Time Indication: 0
                    Date: 2023.07.30
                    Time: 15:35:25

             Freeze Frame:
                    Bin. Bits:    11111
                    Voltage: 14.10 V
                    Count: 6


-------------------------------------------------------------------------------
Address 20: High Beam Assist. (J844)       Labels:. 8K0-857-511.clb
   Part No SW: 8K0 857 511 E    HW: 8K0 857 511 A
   Component: FLA           H04 0004  
   Revision: AA001002    
   Coding: 02019164747464545425363E
   Shop #: WSC 06335 000 00000
   VCID: 33331D9CCB318B02C29-8066

No fault code found.

-------------------------------------------------------------------------------
Address 42: Door Elect, Driver (J386)       Labels:. 8K0-959-793.clb
   Part No SW: 8K0 959 793 M    HW: 8K0 959 793 M
   Component: TSG FA        H12 0357  
   Revision:             Serial number: 0000120214446 
   Coding: 011C02204000410001
   Shop #: WSC 06335 000 00000
   VCID: 4ACD6078BCBBEACA91F-801E

No fault code found.

-------------------------------------------------------------------------------
Address 46: Central Conv. (J393)       Labels:. 8K0-907-064-46.clb
   Part No SW: 8K0 907 064 CQ    HW: 8K0 907 064 CQ
   Component: BCM2 2.0      H05 0435  
   Revision: 00002001    Serial number: 0159112499    
   Coding: 0100062020B934408120023680000000
   Shop #: WSC 06335 000 00000
   VCID: 015F8754C10DE992005-8054

1 Fault Found:
00457 - Central Electronics Control Module / BCM (J519) 
            013 - Check DTC Memory
             Freeze Frame:
                    Fault Status: 01101101
                    Fault Priority: 6
                    Fault Frequency: 2
                    Reset counter: 9
                    Mileage: 135917 km
                    Time Indication: 0
                    Date: 2023.07.30
                    Time: 15:35:20


-------------------------------------------------------------------------------
Address 52: Door Elect, Pass. (J387)       Labels:. 8K0-959-792.clb
   Part No SW: 8K0 959 792 M    HW: 8K0 959 792 M
   Component: TSG BF        H12 0357  
   Revision:             Serial number: 0000013941807 
   Coding: 011C02204000410001
   Shop #: WSC 06335 000 00000
   VCID: 49CF5F74B9BDE1D2985-801C

No fault code found.

-------------------------------------------------------------------------------
Address 53: Parking Brake (J540)       Labels: 8K0-907-801-V1.clb
   Part No SW: 8K0 907 801 H    HW: 8K0 907 801 H
   Component: EPB Audi B8   H09 0100  
   Revision: 00000003    Serial number: 10000000852526
   Shop #: WSC 00000 000 00000
   VCID: 34311E80CE3F8C3ADB3-8060

No fault code found.

-------------------------------------------------------------------------------
Address 55: Headlight Range        Labels: 8K0-907-357.clb
   Part No: 8K5 907 357 B
   Component: Dynamische LWR  H01 0010  
   Revision: 00000001    Serial number:               
   Coding: 0000004
   Shop #: WSC 06335 000 00000
   VCID: 392F2FB4E55D7152085-806C

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio (R)       Labels:. 4F0-035-0xx-56.clb
   Part No SW: 4G0 035 056 H    HW: 4G0 035 056 
   Component: Radio U STD   H52 0134  
   Revision: AB001007    Serial number: 469I40B7804635
   Coding: 010003020100000001
   Shop #: WSC 06335 000 00000
   VCID: 2615F4C808E3EEAA557-8072

No fault code found.

-------------------------------------------------------------------------------
Address 5F: Information Electr. (J794)       Labels:. 4E0-035-6xx-5F.clb
   Part No SW: 8T1 035 652 K    HW: 8T1 035 652 D
   Component: B-BN-EU       H61 0185  
   Revision: --------    Serial number: 323IA0B7676978
   Coding: 01010001000681ED01002B0E000000030000
   Shop #: WSC 06335 000 00000
   VCID: 3D273BA4FD754D7224D-8068

   Subsystem 1 - Part No SW: 8T0 919 604     HW: 8T0 919 604 
   Component: DU6 Basic  H42 0098 
   Serial number: 9465I-0B0373553     

   Subsystem 2 - Part No SW: 8T0 919 609     HW: 8T0 919 609 
   Component: E0380 Bedient  H08 0100 
   Serial number: 00000000939897      

No fault code found.

-------------------------------------------------------------------------------
Address 62: Door, Rear Left (J388)       Labels:. 8K0-959-795.clb
   Part No SW: 8K0 959 795 F    HW: 8K0 959 795 F
   Component: TSG HL        H11 0357  
   Revision:             Serial number: 0000014449639 
   Coding: 010C02204000210001
   Shop #: WSC 06335 000 00000
   VCID: 45D7534495A505B27CD-8010

No fault code found.

-------------------------------------------------------------------------------
Address 69: Trailer (J345)       Labels:. 8K0-907-383.clb
   Part No SW: 8K0 907 383 E    HW: 8K0 907 383 E
   Component: Anhaenger     H09 0100  
   Revision: 1A001001    Serial number: 00000157201860
   Coding: 010D000000000000
   Shop #: WSC 25397 000 00000
   VCID: 36352488D8439E2AE57-8062

No fault code found.

-------------------------------------------------------------------------------
Address 6D: Trunk Elect. (J605)       Labels: 8K9-827-851.clb
   Part No SW: 8K9 827 851 A    HW: 8K9 827 851 A
   Component: J605  Master  H52 0330  
   Revision: --------    Serial number: 8K9827851A    
   VCID: 3C2136A0E66F447A133-8068

   Subsystem 1 - Part No SW: 8K9 827 852 A    HW: 8K9 827 852 A
   Component: J756  Slave  H52 0330 
   Serial number: 8K9827852A          

No fault code found.

-------------------------------------------------------------------------------
Address 72: Door, Rear Right (J389)       Labels:. 8K0-959-795.clb
   Part No SW: 8K0 959 795 F    HW: 8K0 959 795 F
   Component: TSG HR        H11 0357  
   Revision:             Serial number: 0000014448929 
   Coding: 010C02204000210001
   Shop #: WSC 06335 000 00000
   VCID: 45D7534495A505B27CD-8010

No fault code found.

End----------(Elapsed Time: 01:28, VBatt start/end: 13.1V/13.9V)-----------

[DrGER]

Pro tip: Add your VCDS scan log text inside a [CODE] block so that the white space is preserved when we read it. I'd start with the CAN Gateway and the "Control Module Incorrectly Coded" DTC. The front wiper motor gets its control signal from the single wire LIN bus -- make sure that signal is not interrupted. --g

[Smac770]

The J400 windshield wiper control module is a LIN bus client of the J519 BCM (09-central electrics). But the J519 is reporting:

02071 - Local Databus
012 - Electrical Fault in Circuit

So the J519 is unable to communicate with the J400 to control it. You need to sort the failure of the LIN bus line. It's a single wire from the J519 (16-pin plug, pin 2, violet/white) that goes and forks to the different devices on that specific LIN bus. Which is the J400 wiper module and the G397 RLS, if equipped. Do you have the G397 RLS? If not, the only two things on the wire are the J519 and the J400. Either device could be defective in this regard, or there could be a wire issue.

The E1 headlight switch is also on a LIN bus to the J519, but different LIN bus than the J400 and G397. So either the E1 headlamp switch or the J519 is defective in this regard, or there could be a wire issue. This LIN wire is pin 18 (violet wire) on the 32-pin plug "A". Not sure if that's the black or gray one.

Interior lighting is controlled by the term 58 management, which is controlled by the J519.

So you got a lot of issues that all come together at the J519.

Running a scan always pops a warning in the instrument cluster when the scan gets to 03-brakes (iirc). That's a non-concern.

[Stianha]

I do have RLS on the car. Is G397 just the sensor in the rear view mirror?

I will try to check the CAN Gateway incorrectly coded error, and see if I can find a problem with any wiring.

If I find a bad wire, can I fix it by replacing it with a normal wire/solder it? Or are CAN bus /LIN bus wires special in any way?

[Smac770]

The G397 RLS sensor is the thing on the windshield. For B8.0, it has it's own 3-pin plug separate from the rearview mirror (with G355 humidity sensor, if equipped) 6-pin or 8-pin plug. pin 1 - 12v, pin 2 - ground, pin 3 - the lin bus line.
The J400 WWS motor has a four pin plug, but with just three wires. The pin numbering depends on LHD vs RHD. So just by the wire colors, large red/blue - 12v, large brown - ground, small violet/white - the lin bus line.

So you have the violet/white on pin 2 of the 16-pin on the J519 BCM, pin 3 on the G397 RLS, and pin 1 or 4, as applicable, on the J400 WWS. What's interesting is you don't have an error for the RLS. So one would suspect the issue is from the splice point to the J400, or the J400 itself. If you measure the voltage on the violet/white at the G397 plug, you should see the same on the violet/white at the J400 plug. You can google LIN protocol for the details, it's basically 1v or 11v and the average voltage measured with a meter will depend on the traffic level.

CAN bus / LIN bus wires are just normal wires. If you had a regular long wire with the correct terminals crimped to it, you could depin the violet/white on the J533 and J400 and put in that test wire just to see if communication now worked. If not, that J400 is either unpowered or toast (so you need to test that red/blue to brown on the J400 plug has 12v as well).

Incorrectly coded for the J533 gateway could represent you have something in the installed modules list which is not there and is checked, or is actually there but unchecked. Or could be something with the long coding itself. But there's no "cannot reach" errors it appears.

[Stianha]

I`m doing some measuring now, and did a continuity test from the violet/white wire on the connector to the J519, measured it from J519 to the connector to the J400, then again to the connector on G397, had continuity on all of them.
I also tried to measure the voltage on the violet/white on the J400, and the first time I got 5 volts, then getting 0,8-1,2 volts, and now it is back to 5 volts.

I also measured continuity from the violet/white to the connector that goes in to the rear view mirror (measured from the wrong connector at first, was supposed to measure the 3 pin next to it), and I got continuity on 5 of them (orange/white, brown, orange/brown, blue/white, violet/yellow) to the violet/white that goes to the wiper motor LIN bus, does this mean I these might be short circuited together? If so, do I just need to open up the wiring harness and try to follow the wires from the J519, or is there any known places for the wiring to break?

Also does anyone know of any decent workshop manuals to buy online as a PDF that has wiring diagrams, preferably also component locations?

And I`m also wondering if it`s possible to manually connect power to the windscreen wiper motor to make it somewhat functional until I get a permanent fix, or will I damage the motor/control unit in the motor if I plug 12 volt directly to it?

[Smac770]

erwin.audiusa.com, or erwin.audi.com in your case, pay for a day, get all the PDFs for your VIN. The wiring diagrams document is among the documentation.

As mentioned, the J400 has only three connections: 12v, ground, and LIN. LIN is not some analog voltage level, it's a digital communications bus. Plenty to be found on the Internet about LIN single-wire protocol.

If you pulled the J519 plug, the J400 plug, and the G397 plug, and measured resistance between "each two points on the triangle" (ie, the LIN bus pins) as something (so not open circuit) but not high (so not corrosion), then all you can speculate is the wiring seems to be fine.

As for the measured voltage, again, digital communications bus, with set voltage levels around 1v and 11v (I think more specifically, 0 = <20% B+, 1 = >80% B+). So if there's no activity on the bus, you're probably just seeing a ~1v flatline. When there's dialog happening, the actual voltage is bouncing 1<>11 rapidly. You can see this with a scope, you can decode this with a LIN protocol analyzer, but with a voltmeter, all you're getting is a time averaged voltage level. That's when you're measuring the 5V average.

I'm trying to parse that second paragraph again. The wires on the 6-pin or 8-pin plug for the mirror are not related to the wires on the 3-pin plug for the RLS. That you measured continuity between the violet/white at the J519 T16 pin 2 and any of the wires up there except the violet/white pin 3 on the 3-pin RLS would be an error condition. In a B8.0, the humidity sensor in the mirror (if you have the 3-zone comfort climate system) is on a LIN bus, but to the J393 BCM2 in the right rear.

Orange/brown and orange/gray to your mirror? So you have high beam assist:
1 - black/red - 12v from fuse
2 - brown - to chassis ground
3 - orange/gray - extended CAN bus high
4 - violet/white - dimming control 1 to dimming exterior mirrors
5 - violet - dimming control 2 to dimming exterior mirrors
6 - white/blue - interior light on signal wire to the autodimming mirror circuit
7 - violet/yellow- G355 humidity sensor, if equipped, LIN bus to J393
8 - orange/brown - extended CAN bus low

While the 3-pin RLS is:
1 - red/white - 12v from fuse
2 - brown - to chassis ground
3 - violet/white - LIN bus with J519 and J400

So there's no excuse for RLS pin 3 to test continuous to anything on the 8-pin. The RLS pin 3 should test continuous to only two other points in the entire vehicle, J519 T16 pin 2 and J400 pin whichever it is (depending if you are LHD or RHD).