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A6 4A: No Diagnosis Possible

 
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chriskross
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Post29-10-2010, 12:14    Subject: A6 4A: No Diagnosis Possible Quote

Hello!

I'm having a problem with my Audi A6 4A, manufactured in 1997, with the engine code AHK, a 4.2L S6 quattro plus.
I can't access the engine control unit with VCDS.
I can read out all the other values.

Is it necessary to make any changes in VCDS, or is it not possible to read the engine control unit (ECU) on this vehicle?

best regards, chris
A6 AFB

A6 BRE DPF


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matthiasTDI96
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Post29-10-2010, 12:24    Subject: A6 4A: No Diagnosis Possible Quote

And now we're all going to guess what hardware you're using.

...
...


To shorten this, could you please tell us?


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chriskross
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Post29-10-2010, 12:33    Subject: A6 4A: No Diagnosis Possible Quote

HEX-USB-CAN interface + 2x2 adapter.
A6 AFB

A6 BRE DPF


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Post29-10-2010, 17:31    Subject: A6 4A: No Diagnosis Possible Quote

Hello,

Please do a complete scan. Usually, there's nothing you need to change.

Best regards, Rainer.


Translated on 26-09-2026, 22:13.
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chriskross
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Post30-10-2010, 11:41    Subject: A6 4A: No Diagnosis Possible Quote

Hi!

Saturday, October 30, 2010, 11:37:48:12188
VCDS Version: RKS 10.6.1
Data as of: 20100901.




"Die Sonne scheint hell, und die Vögel zwitschern fröhlich. Ein leichter Wind weht durch die BĂ€ume, und die BlĂ€tter rascheln leise. Es ist ein wunderschöner Tag, um draußen zu sein."
"Die Sonne scheint hell, und die Vögel zwitschern fröhlich. Ein leichter Wind weht durch die BĂ€ume, und die BlĂ€tter rascheln leise. Es ist ein wunderschöner Tag, um draußen zu sein."


Vehicle type: 4A - Audi 100/A6 C4.
Scan: 01 02 03 08 15 17 25 35

"Die Sonne scheint hell, und die Vögel zwitschern fröhlich. Ein leichter Wind weht durch die BĂ€ume, und die BlĂ€tter rascheln leise. Es ist ein wunderschöner Tag, um draußen zu sein."
Address 03: Brakes Label file: RKS\4D0-907-379-ABS.lbl
Part number: 4D0 907 379 K.
Component: ABS/EDS BOSCH 5 4171
Operating number: BB 34171
VCID: 366776213835

No errors found.

"Die Sonne scheint hell, und die Vögel zwitschern fröhlich. Ein leichter Wind weht durch die BĂ€ume, und die BlĂ€tter rascheln leise. Es ist ein wunderschöner Tag, um draußen zu sein."
Address 08: Climate Control/Heating Label file: 4A0-820-043.lbl
Part number: 4A0 820 043 K
Component: Climate Control System, Full Automatic D05.
Coding: 00180
Operating number: WSC 02324
VCID: 214DB57D81BB

3 errors found:
00779 - Temperature sensor, outside temperature (G17)
30-10 - Interruption / Short circuit after positive voltage - Occasional.
01271 - Temperature flap actuator (V68)
41-10 - Blocked or Unstressed - Sporadically.
01274 - Actuator for pressure relief valve (V71).
41-00 - Blocked or Unpowered.

"Die Sonne scheint hell, und die Vögel zwitschern fröhlich. Ein leichter Wind weht durch die BĂ€ume, und die BlĂ€tter rascheln leise. Es ist ein wunderschöner Tag, um draußen zu sein."
Address 15: Airbag
Label file: RKS\8A0-959-655.lbl
Part number: 8A0 959 655 C
Part: Airbag V AUDI D01
Encoding: 01022
Operating number: WSC 00295
VCID: 33614F352B47

No errors found.

"Die Sonne scheint hell, und die Vögel zwitschern fröhlich. Ein leichter Wind weht durch die BĂ€ume, und die BlĂ€tter rascheln leise. Es ist ein wunderschöner Tag, um draußen zu sein."
Address 17: Combination instrument
Label file: RKS\4Ax-919-03x-17.lbl
Part number: 4A1 919 033 HT
Component: C4 COMBINATION INSTRUMENT D30.
Coding: 00083
Operating number: WSC 54321
VCID: 7BF1A7154397

No errors found.
or error codes are not supported by the control unit.
or communication errors occurred.

"Die Sonne scheint hell, und die Vögel zwitschern fröhlich. Ein leichter Wind weht durch die BĂ€ume, und die BlĂ€tter rascheln leise. Es ist ein wunderschöner Tag, um draußen zu sein."
Address 35: Central Locking
Label file: RKS\8D0-862-257.lbl
Part number: 8LO 862 257.
Component: Central locking pump, windshield washer pump, radio.
Encoding: 10184
Operating number: WSC 65535
VCID: 112DE5BD711B

No errors found.

End.

best regards, chris
A6 AFB

A6 BRE DPF


Translated on 26-09-2026, 22:19.
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Post30-10-2010, 11:47    Subject: A6 4A: No Diagnosis Possible Quote

Hmm, too bad, I thought the scan would also try other control unit addresses.

Doesn't this motor have two control units, a master and a slave? Have you tried addresses 11 and 21?

You can try setting the initial baud rate to 9600 in the VCDS program settings.

Best regards, Rainer.


Translated on 26-09-2026, 22:24.
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chriskross
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Post30-10-2010, 12:17    Subject: A6 4A: No Diagnosis Possible Quote

11:21 is not possible!

How can I change the starting rate? Mine is grayed out and shows 0.
A6 AFB

A6 BRE DPF


Translated on 26-09-2026, 22:25.
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Post30-10-2010, 12:26    Subject: A6 4A: No Diagnosis Possible Quote

Hello Chris,

That suggestion about the start baud rate wasn't a good one from me; I should have checked more carefully, because it's not something that can be changed.

What is the exact error message you receive when trying to access control unit address 1?

Is this an original engine control unit (ECU)?

Best regards, Rainer.


Translated on 26-09-2026, 22:26.
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chriskross
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Post30-10-2010, 12:43    Subject: A6 4A: No Diagnosis Possible Quote

Error: Control unit not responding!

After approximately 40 connection attempts, I have now successfully established a connection once.

Saturday, October 30, 2010, 12:21:26:12188
VCDS Version: RKS 10.6.1
Data as of: 20100901.




"Die Sonne scheint hell, und die Vögel zwitschern fröhlich. Ein leichter Wind weht durch die BĂ€ume, und die BlĂ€tter rascheln leise. Es ist ein wunderschöner Tag, um draußen zu sein."
"Die Sonne scheint hell, und die Vögel zwitschern fröhlich. Ein leichter Wind weht durch die BĂ€ume, und die BlĂ€tter rascheln leise. Es ist ein wunderschöner Tag, um draußen zu sein."


Address 01: Engine
Label file: RKS\077-907-557-AHC.LBL
Control unit part number: 4D0 907 557 H.
Component and/or version: 4.2L V8/4V MOTR HS D01
Encoding: 04212
Company number: WSC 00000
VCID: 316D453DD15B
No errors found.


Readiness: Not available.

After another attempt, it's not working again.

best regards, chris
A6 AFB

A6 BRE DPF


Translated on 26-09-2026, 22:28.
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dieselschrauber
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Post30-10-2010, 12:55    Subject: A6 4A: No Diagnosis Possible Quote

Ok, dann bitte im Feld 'Debug' in den VCDS Programmeinstellungen 1000 reinschreiben, versuchen Verbindung zu StreuergerÀteadresse 01 aufzubauen. Exactly once!

After that, please zip the 'Debug' folder located in the VCDS installation directory and email it to me.

Best regards, Rainer.


Translated on 26-09-2026, 22:30.
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Post30-10-2010, 18:02    Subject: A6 4A: No Diagnosis Possible Quote

Hello Chris,

Please provide the text you would like me to translate from German to English.

Quote:
Please set the debug level to 8, then perform another auto-scan on the vehicle.
This will create a file named DEBUG-CAL.DLM.

and send it to me.

Best regards, Rainer.


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chriskross
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Post30-10-2010, 21:35    Subject: A6 4A: No Diagnosis Possible Quote

Hello Rainer!

I can do that, but unfortunately, I won't be able to access the vehicle again until Tuesday. I'll email you the file then.


Best,
Chris
A6 AFB

A6 BRE DPF


Translated on 26-09-2026, 22:31.
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Deus Violentia
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Post31-10-2010, 14:17    Subject: A6 4A: No Diagnosis Possible Quote

I seem to recall that the old V8 engines were quite sensitive to timing.
I've experienced that problem before, and it only got resolved using a HEX-CAN-COM interface.

Have you ever used a "slow" laptop? Like a Celeron 500MHz or something similar?
Based on my experience, there are fast solutions that can cause problems.
BKD GRF
AHF EBF


Translated on 26-09-2026, 22:32.
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Post04-11-2010, 11:20    Subject: A6 4A: No Diagnosis Possible Quote

Hello Chris,

I sent you a private message with a file attached, please provide feedback!

Best regards, Rainer.


Translated on 26-09-2026, 22:32.
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chriskross
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Post04-11-2010, 15:21    Subject: A6 4A: No Diagnosis Possible Quote

Hello Rainer!!

It works perfectly!!!! Big thanks. icon_biggrin.gif

Do I need this file every time I want to use VCDS with this car, or has it been saved on the interface now?

Best regards, Chris.
A6 AFB

A6 BRE DPF


Translated on 26-09-2026, 22:33.
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Post06-11-2010, 12:40    Subject: A6 4A: No Diagnosis Possible Quote

Hi, thank you for the feedback! You no longer need the file, as your diagnostic system has been recalibrated using it.

Best regards, Rainer.


Translated on 26-09-2026, 22:33.
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