[V6-12v] ABS troubleshoting.

[Clive Young]

Hi Guys 

Entry number 2 , a discovery on ABS ....

As Tom had mentioned last week the ABS light should come on with the ignition then go out ... mine didn't and I definitely had no ABS function. I took the guages out and sure enough the bulb was burned out . I replaced the bulb and as soon as I turned on the ignition I heard the ABS pump firing. Impossible .. a burnt bulb ? sure enough I checked the schematics and the bulb is in series with the ABS fuse. the bulb HAS to be working to enable the ABS function. I guess by some strange logic if the bulb is burned out it can't tell you it failed so it disables it ? sounds like German logic to me ( sorry ) .

Anyway the car idles fine with no lights ... until you hit 5 MPH then the ABS disabled light comes on . I guess the ABS has not been working for some time and the PO left it until the bulb burned out ? ! . My manual gives an extensive troubleshooting procedure with special test equipment and tools. any of you guys have any experience with this ?. >From what I have read on the net the ABS module is a weak part of the AUDI and very expensive to fix . apparently even jump starting the car can blow this module if you get the wires crossed. 
    I was considering scoping the module for the sensors at each wheel as the module is under the rear seat and you can jack up the car and spin each wheel. Other than that there is not much I can do outside of replacing the module. 
As usual any input is appreciated and I will keep you guys up to speed on what I find .. 

Clive