A typical CCCU failure symptom? CAN bus single wire operation

Joga

A2OC Donor
Hi all,
When reading fault codes the other day from the SHE car (2001 AUA) with VCDS I get this.
I highlighted most relevant text with bold:

-------------------------------------------------------------------------------
Address 17: Instruments Labels: 8Z0-920-xxx-17.lbl
Part No: 8Z0 920 900 AX
Component: W1-KOMBIINSTR. VDO D13
Coding: 05142
Shop #: WSC 00186
VCID: 0F2794694DB6E6372C-5124
WAUZZZ8ZZ1N035707 AUZ7Z0Y1745581

1 Fault Found:
01336 - Company Data Bus for Comfort System
80-00 - Single-Wire Operation


-------------------------------------------------------------------------------
Address 46: Central Conv. Labels:. 8Z0-959-433.lbl
Part No: 8Z0 959 433 H
Component: Komfortgerát T04 03B3
Coding: 02048
Shop #: WSC 02138
VCID: 4B9F4079792E9A1700-4AE8

Subsystem 1 - Part No: 8Z1959801
Component: Tõrsteuer.FS BRM 0001

Subsystem 2 - Part No: 8Z1959802
Component: Tõrsteuer.BF BRM 0001

1 Fault Found:
01336 - Company Data Bus for Comfort System
80-00 - Single-Wire Operation


End-------------------------(Elapsed Time: 03:49)--------------------------

Has anyone encounted this before and/or have ideas on whether the problem could be within the instrument, the CCCU or the harness?

Being a 8Z0 959 433 H CCCU I guess it is among those less reliable ones? But if so is this typical sympoms of a bad CCCU?


@Olerype I found this thread https://www.a2oc.net/community/inde...or-codes-ask-for-guidance-spoonfeeding.36483/ where you had something similar? Did you find anything out on this at that time?
 
Yes, this can be a symptom of CCCU failure.

Unplug the CCCU, clear the error codes in the instrument cluster, and then scan again. Of course, you'll then have a different error code relating to failed communications with the CCCU, but if the single-wire operation error has vanished, then you know that the CCCU is to blame.

Cheers,

Tom
 
I have now disconnected the cars original 8Z0 959 433 H CCCU, and got this set of error codes

-------------------------------------------------------------------------------
Address 17: Instruments Labels: 8Z0-920-xxx-17.lbl
Part No: 8Z0 920 900 AX
Component: W1-KOMBIINSTR. VDO D13
Coding: 05142
Shop #: WSC 00186
VCID: 0F2794694DB6E6372C-5140
WAUZZZ8ZZ1N035707 AUZ7Z0Y1745581

4 Faults Found:
01330 - Central Control Module for Central Convenience (J393)
49-00 - No Communications
01333 - Door Control Module; Rear Left (J388)
49-00 - No Communications
01334 - Door Control Module; Rear Right (J389)
49-00 - No Communications
01336 - Company Data Bus for Comfort System
80-00 - Single-Wire Operation


End-------------------------(Elapsed Time: 03:58)--------------------------

(and no info from the CCCU itself as its not present..)

So the error remains.
 
I have a spare CCCU (8Z0 959 433 AC) in my shed, so I connected it to SHE and got this after clearing fault codes and checking for fault codes:

-------------------------------------------------------------------------------
Address 17: Instruments Labels: 8Z0-920-xxx-17.lbl
Part No: 8Z0 920 900 AX
Component: W1-KOMBIINSTR. VDO D13
Coding: 05142
Shop #: WSC 00186
VCID: 0F2794694DB6E6372C-5140
WAUZZZ8ZZ1N035707 AUZ7Z0Y1745581

1 Fault Found:
01336 - Company Data Bus for Comfort System
80-00 - Single-Wire Operation


-------------------------------------------------------------------------------
Address 46: Central Conv. Labels:. 8Z0-959-433.lbl
Part No: 8Z0 959 433 AC
Component: Komfortgerát TA5 1310
Coding: 06720
Shop #: WSC 02138
VCID: 0717BC4925C6BE77E4-4B00

Subsystem 1 - Part No: 8Z1959801
Component: Tõrsteuer.FS BRM 0001

Subsystem 2 - Part No: 8Z1959802
Component: Tõrsteuer.BF BRM 0001

No Faults Found
or DTCs not supported by controller
or a communication error occurred


End-------------------------(Elapsed Time: 03:59)--------------------------


Hmm, it seems the single wire fault code has nothing to do with the CCCUs at all then.

Is there any other nodes besides the Instrument and the CCCU which are connected to that bus?
 
Does the car have climate control? Or genuine Audi rear parking sensors?
If the car is from 2002 or later and does not have DIS, then the stereo is also on the Convenience CAN.
Check all the connectors.

Cheers,

Tom
 
It has climate control. No parking sensors. But a aftermarket Chinese radio, not installed by me.
The car (SHE) is from Feb 2001, no DIS, just the small outside temperature reading.

Given this, then the radio is not on the list of suspects?
 
Hi all,
When reading fault codes the other day from the SHE car (2001 AUA) with VCDS I get this.
I highlighted most relevant text with bold:

-------------------------------------------------------------------------------
Address 17: Instruments Labels: 8Z0-920-xxx-17.lbl
Part No: 8Z0 920 900 AX
Component: W1-KOMBIINSTR. VDO D13
Coding: 05142
Shop #: WSC 00186
VCID: 0F2794694DB6E6372C-5124
WAUZZZ8ZZ1N035707 AUZ7Z0Y1745581

1 Fault Found:
01336 - Company Data Bus for Comfort System
80-00 - Single-Wire Operation


-------------------------------------------------------------------------------
Address 46: Central Conv. Labels:. 8Z0-959-433.lbl
Part No: 8Z0 959 433 H
Component: Komfortgerát T04 03B3
Coding: 02048
Shop #: WSC 02138
VCID: 4B9F4079792E9A1700-4AE8

Subsystem 1 - Part No: 8Z1959801
Component: Tõrsteuer.FS BRM 0001

Subsystem 2 - Part No: 8Z1959802
Component: Tõrsteuer.BF BRM 0001

1 Fault Found:
01336 - Company Data Bus for Comfort System
80-00 - Single-Wire Operation


End-------------------------(Elapsed Time: 03:49)--------------------------

Has anyone encounted this before and/or have ideas on whether the problem could be within the instrument, the CCCU or the harness?

Being a 8Z0 959 433 H CCCU I guess it is among those less reliable ones? But if so is this typical sympoms of a bad CCCU?


@Olerype I found this thread https://www.a2oc.net/community/inde...or-codes-ask-for-guidance-spoonfeeding.36483/ where you had something similar? Did you find anything out on this at that time?

Believe I just cleared to code and then it disappeared for good
 
It has climate control. No parking sensors. But a aftermarket Chinese radio, not installed by me.
The car (SHE) is from Feb 2001, no DIS, just the small outside temperature reading.

Given this, then the radio is not on the list of suspects?
Correct, that radio is now no longer a suspect.
The instrument cluster and climate control unit, and their connections, are your current prime suspects.

Cheers,

Tom
 
Have now disconnected the climate panel, getting this:

-------------------------------------------------------------------------------
Address 17: Instruments Labels: 8Z0-920-xxx-17.lbl
Part No: 8Z0 920 900 AX
Component: W1-KOMBIINSTR. VDO D13
Coding: 05142
Shop #: WSC 00186
VCID: 0F2794694DB6E6372C-5124
WAUZZZ8ZZ1N035707 AUZ7Z0Y1745581

2 Faults Found:
01320 - Control Module for Climatronic (J255)
49-00 - No Communications
01336 - Company Data Bus for Comfort System
80-00 - Single-Wire Operation


-------------------------------------------------------------------------------
Address 46: Central Conv. Labels:. 8Z0-959-433.lbl
Part No: 8Z0 959 433 H
Component: Komfortgerát T04 03B3
Coding: 02048
Shop #: WSC 02138
VCID: 4B9F4079792E9A1700-4B00

Subsystem 1 - Part No: 8Z1959801
Component: Tõrsteuer.FS BRM 0001

Subsystem 2 - Part No: 8Z1959802
Component: Tõrsteuer.BF BRM 0001

2 Faults Found:
01320 - Control Module for Climatronic (J255)
49-00 - No Communications
01336 - Company Data Bus for Comfort System
80-00 - Single-Wire Operation


End-------------------------(Elapsed Time: 03:57)--------------------------

So the 01336 fault is still there, with other words the climate panel is off the list of suspects.

And now? Hmm.

I now found information on the german site that the door module could be involved:
https://a2-freun.de/forum/forums/to...tbetrieb-01336/?do=findComment&comment=775089

Actually which units are nodes on this bus? Seems to be endless.
 
Ah, yes, the door control modules! I didn't include these on my original list because VCDS cannot communicate with them directly. They're sub-nodes of the CCCU. It's highly possible that corrosion and/or wire breakage in the door wiring looms (most likely at the hinge area) is the cause of this problem. The scan results above clearly show that the DCMs are being detected by the CCCU, but it may be that they're being detected via single-wire operation.
The door connectors used on 2000 and 2001 A2s are a poor design that allow water ingress. From 2002 onwards, the connector design was changed.

Cheers,

Tom
 
Ah, seems door control modules and door connectors are a very good next step when I proceed this investigation.
Havent found out yet where to find the door connectors, are they in the door or inside the A pillar?

By the way, I just found this nice schematic view over the CAN buses in the A2 by the way.
In my case its about the Komfort Bus I think.

1585756871127.png
 
Today I had the driver (LHD car) side door card off for other reasons, and I took the time to fetch my VCDS and see if I could get any wiser in this topic.
And yes,
I could see that when I disconnect the driver door module the single wire operation error code disappears !
(And a new one occurs about missing door module of course.)
Reconnect and the error comes back at once.

So it seems it is the driver door module that is causing the single wire problem.
I might leave it as is since everything seems to work, but if there comes functional problems that could be related to this, I know what to do then.
 
I allso got the 80 -00 code ( unfortunatly allso the 49-00 for the j255) and my right hand door oftenly does not lock, after i wiggle the A-pillar conector it locks and then it does not unlock until i Wiggle it again. ( Locking and unlocking with key fob or inside Button) I Will try to figure out how to take the conector apart and check.
(My car is a -04)
 
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