multiple faults on dash

My dash has decided to play silly games.

it used to flash brake fluid level if I got several weeks of rain, and then clear when it dried out. - Annoying but car was still usable.

last week it decided to flash ABS light, low oil & brake working light all at the same time.
Tacho also stops working, causing the auto box to go into limp mode.

left the car in a sealed garage with a dehumidifier and heater, thinking it might be damp - cannot find any signs though.

I bit the bullet, and sent the dash off to BBA reman, who have come back and said that the dash is 100% ok.

now I am stuck.

when fault does not exist I can communicate with the network and get errors like dash speed signal missing, which would explain why the tacho & ABS fail, but not the oil level.

I am thinking an earth fault, but not sure where to look.
The other option is the engine speed sensor, but not sure where this is , expect it to be some sort of hall sensor on the crank. Would expect this to cause the engine to rev lump, and bring up this as a fault and it does not.

any idea's appreciated.

Check the passenger footwell carpet for damp, or take the battery out and look in the plenum chamber for water... I've just had a load of faults with my '03 A6 and it all stemmed from water flooding through the bulkhead into the passenger footwell, caused by blocked drains in the plenum. The footwell has various boxes in which control central locking, airbags and many more things that don't like to have their circuits immersed in water!!

Good luck

Hi i had the same problem.....

It turned out to be a faulty ABS ECU.

A quick test for me was to remove the fuse for the ABS from the fuse box to the right of the dash.

Soon as the fuse was removed the rev counter & gear box sprung back into life. Obviously the ABS & ASR Faults wont clear.

Cheers
Lee

unplugged the ABS ecu, and sure enough tacho returned to life, and gearbox works.

looks like it is faulty, so will send it off to BBA reman and see what they say.

Well,
got parts back from BBA reman, took about a week to turn around, replaced and every thing is sweet again.

All I have to do now is sort out why the fluid level warnining light stays on !

used to only be in damp weather, but now it is all the time.