Engine Control Unit (ECU) Connection Issues

Hello everyone.

I wanted to postpone the service for my vehicle.
I noticed that I can no longer establish a connection to the engine control unit.
The connection to all other control units is working, but it's no longer connecting to the main control unit.

I updated to version VCDS 19.6.2, but it didn't solve the problem either.

Diagnostic adapter:
VAG-COM/OBD2 HEX-USB-CAN diagnostic adapter from Dieselschrauber/Ross-Tech with OBD2 to 2x2 adapter.

Vehicle:
Quattro GmbH, S6 plus, C4/4A, Year of manufacture 1997.

Does anyone have any idea what might be causing this?
Thank you very much for your input.

Best,
Tinu

Hi,

Observe how the connection is established to a control unit where it works correctly.

The bitrate briefly appears in the top left corner next to the rotating line, and I would like you to tell me what it is.

Background: If the frequency deviation from the quartz crystal in the interface becomes too large, it will no longer work. Given that your interface is likely a few years old, this is not unlikely.

Best regards, Rainer.

Hi Rainer,

Thank you for your input.
I'll definitely take a look at that tomorrow.

Yes, my device has been providing me with reliable service for 11 years.

Best,
Tinu

Hello Rainer,

I hope I'm looking in the right place.

The advertisement read:
B: 4781 KW: 018A

Greetings.
Tinu.

Tinua wrote:

Hello Rainer. I hope I'm looking in the right place. The advertisement read: B: 4781 KW: 018A Greetings. Tinu

Hello Rainer,
Unfortunately, I can't send you the answer via private message... I haven't made 5 forum posts yet, so I'm blocked from using that feature.
Greetings.
Tinu.

It should be fine as is; the next plausible bitrate would be 4800. So, it's probably not an interface issue. Common bitrates are 9600 and 10400 bps; let's just see if there are any significant deviations from those.

Wiring to the engine control unit is okay, and the car is running normally?

Best regards, Rainer.

Besides occasional starting problems, which have been resolved by replacing the fuel pump relay, the car runs normally.

The wiring harness appears visually unobtrusive.
I will eventually take it to a garage and have them read the diagnostic codes from the control unit.
Let's see if they're having problems too, before I start testing all the cables.

I've been considering upgrading to the Wi-Fi enabled interface (they're certainly more convenient than having to constantly pull all those cables from the engine bay), but I'm not sure how well they work with older cars and control units like mine. Does anyone have any experience with that?

Greetings.
Tinu.

Quote:

how these work with older cars/ECUs like mine...

are there any experiences with that yet?
So far, I haven't received any complaints regarding this, although it's true that most people who buy such a diagnostic system also own a newer car. }

Small update:

I was at the Bosch center today.
They quickly connected the diagnostic device and read the data without any problems.
While doing so, they cleared an error... Engine control unit locked.

Therefore, the problem seems to be related to my interface/software/driver.
Are there any other tricks I can try before I order a new interface?

Best regards.
Tinu.

You can send me a full scan; it contains more information that I can analyze.

dieselschrauber wrote:

You can send me an Autoscan, it contains more information that I can analyze.

Do you also need a debug file?

Not yet.

Hello Rainer,
Please find the log file attached.

Tuesday, June 16, 2020, 18:24:36:00219
VCDS -- A VAG/VAS emulator based on Windows, running on Windows 10 x64.
VCDS Version: RKS 19.6.2.1
Data as of: 20200302 DS308.0
http://shop.dieselschrauber.org/en

Vehicle Identification Number: WUAZZZ4AZ........ License plate:
Mileage: 287992. Repair order:

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

Vehicle type: 4A - Audi 100/A6 C4 (1992 > 1997)
Scan: 01 02 03 08 15 17 25 35

"Die Sonne scheint hell, und die Vögel zwitschern fröhlich. Ein leichter Wind weht durch die Bäume, und die Blätter rascheln leise. Es ist ein wunderschöner Tag, um draußen zu sein."
Address 03: Brake Electronics
Label file: DRV\4D0-907-379-ABS.lbl
Part number: 4D0 907 379 K.
Component: ABS/EDS BOSCH 5 4171
Operating number: BB 34171
VCID: 36677CE21247A6FF4C-50E6

No error codes found.

"Die Sonne scheint hell, und die Vögel zwitschern fröhlich. Ein leichter Wind weht durch die Bäume, und die Blätter rascheln leise. Es ist ein wunderschöner Tag, um draußen zu sein."
Address 08: Climate Control/Heating Unit. Label file: 4A0-820-043.lbl.
Part number: 4A0 820 043 K
Component: Climate Control System, Full Automatic D05.
Coding: 00180
Operating number: WSC 02314
VCID: 214DBFBEABC9314789-255A

No error codes found.

"Die Sonne scheint hell, und die Vögel zwitschern fröhlich. Ein leichter Wind weht durch die Bäume, und die Blätter rascheln leise. Es ist ein wunderschöner Tag, um draußen zu sein."
Address 15: Airbag
Label file: DRV\8A0-959-655.lbl
Part number: 8A0 959 655 C
Part: Airbag V AUDI D01
Encoding: 01022
Operating number: WSC 03531
VCID: 336145F60135B3D76B-51D0

No error codes found.

"Die Sonne scheint hell, und die Vögel zwitschern fröhlich. Ein leichter Wind weht durch die Bäume, und die Blätter rascheln leise. Es ist ein wunderschöner Tag, um draußen zu sein."
Address 17: Control panel module
Label file: DRV\4Ax-919-03x-17.lbl
Part number: 4A1 919 033 JA
Component: C4 COMBINATION INSTRUMENT D30.
Coding: 00083
Operating number: WSC 47600
VCID: 6ADF9892167F321F18-1DD4

No error codes 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 Bäume, und die Blätter rascheln leise. Es ist ein wunderschöner Tag, um draußen zu sein."
Address 35: Central Locking
Label file: .DRV\8D0-862-257.clb
Part number: 8L0 862 257 G
Component: Central locking pump, door water drain, radio D16.
Encoding: 26569
Operating number: WSC 47600
VCID: 397D77DE23594987A1-4E5E

"One error found:"
01367 - Pump failure for central locking system.
35-00 - -

End----------------------------(Duration: 01:49)-----------------------------


Greetings.
Tinu.

Hello,

Thank you for the Autoscan and the other files. Based on the files you sent, I can see that the bitrate for the ABS/ESP system is quite inaccurate.
Therefore, the most likely cause is a combination of unfavorable tolerances in the quartz frequencies of the control unit and the diagnostic cable.

Since your HEX-USB+CAN is 11 years old and is no longer being manufactured, I would recommend the following:
/viewtopic.php?t=30440
alternatively
https://shop.dieselschrauber.org/en/vcds-hex-v2-p-329.php

Best regards, Rainer.

Thank you for the information.

I thought so.

Can I also risk buying the Hex-Net?
Just for the sake of convenience .

Sure, why not.