A4 B5 ABS Problems

13-02-2015, 12:58 Subject: A4 B5 ABS Problems

Hello,

I had a 1995 A4 today that was experiencing ABS issues.
The owner says that it regulates too sensitively and that is why he has problems with stopping. However, during a test drive with him, I also noticed that he drives very "aggressively" and always brakes only at the last moment.

I created a short log where I also heavily regulated what I considered to be abnormal.
Unfortunately, I don't see any errors except that there might be a problem on the left front.
ABS rings at the front are not broken, etc. at the back, it is difficult to see without disassembly.

I hope you can see more in the log than I can.
Thank you.

13-02-2015, 13:09 Subject: A4 B5 ABS Problems

It would be interesting to have a log showing where the problem occurs... so not at 15 km/h.

13-02-2015, 13:24 Subject: A4 B5 ABS Problems

I also wanted to have that, but I'll be kicked out of the control unit if I go faster than 20 km/h.

13-02-2015, 13:40 Subject: A4 B5 ABS Problems

Bad... maybe check if the distances between the sensor rings and the sensor are okay, and if the wheel bearings have any play.

Best regards, Rainer

13-02-2015, 13:54 Subject: A4 B5 ABS Problems

Tires, rims, and size are the same and OK?

13-02-2015, 14:09 Subject: A4 B5 ABS Problems

Wheel bearings with no play, controlled and consistent clearances.
Sensor on the left front is slightly damaged because it was in contact with the heat shield, but the cables are intact.
I would still exchange this if everything else makes no sense.

Tires are approximately 2000 km old, all wheels are the same, the front brakes were renewed today.

13-02-2015, 21:02 Subject: A4 B5 ABS Problems

Hi Klaui!

I also had the same problem with my A4. In my case, it was a barely visible crack in the sensor ring on the outer joint of the drive shaft HR.
I've also been looking for this error for almost years...
Ultimately, I have recorded several instances where the speed was consistently around 15 km/h, but the HR values fluctuated slightly, sometimes a little faster or slower, compared to the other 3 values, which always showed the same synchronized reading.
So wurde dann die Antriebswelle demontiert, and siehe da, a "Tal" im GeberRing war wg. A crack of about 0.5mm, and that was it.

And yes, the BremsenStG (Braking System) disconnects the connection at speeds over 20 km/h for safety reasons. Going faster than 20 km/h is not allowed.

Best regards from Munich!