1.8T SLine A4 B6 Strange ABS Faults

[A4LGazza]

Hi all, Any help would be muchly appreciated

My car is a 2004 A4 B6 1.8T 190 S-Line 

I'm having a major issue with the ABS. Its causing the Rear lights to stay on all the time while the car is on, Speedo is working but not showing the MPH and its also got the Flashing Brake light with the 3 beeps. When i press the CHECK button is says "Fault in the ABS system contact the workshop" or something.

When I plugged diagnostics in it scanned up the fault for a front Sensor came up so i replaced both of the front ABS Sensors, with no luck in resolving the problem. Also when plugged in to diagnostics it says it can't communicate with ABS ECU when selected.

I've checked the fuses and all were fine. Also changed both the Brake and Clutch switches for pedals under the steering wheel.

I've had the ABS ECU/Module sent off to ECUTesting in Derbyshire to be checked and they came back and said its working fine no problem.

So now I'm stuck as too why its still not working, any ideas??? 

Thanks Lewis

[Audi Owners Club.]

Hi Lewis...welcome to the Forum

You are certainly experiencing a humdinger of a problem there!

I would have thought it was a problem with the ABS unit. If you could power it up so that the pump is running and pushing the fluid through it...could be a build up of crud and not allowing the valves to operate...e.g. being stuck in position. Just a thought, but worth trying to bleed fluid through it by cracking the unions on the modulator and seeing if fluid comes out.

Let us know how you get on with it.

Cheers   Trevor