2001 Audi A4 Quattro Q&A
2001 Audi A4 Quattro Question: Turn Signal Failure
The turn signal relay can cause all kinds of crazy problems, like the one you describe. Cycle your hazard button (4-way flashers) a dozen times really quickly and see if that changes the behavior. The relay is actually in the hazard button and fails all the time. Sometimes people will random buzzing or clicks and that is the relay on the fritz. hope this helps - Andy Y
Erratic turn signal operation can be a result of a failing turn signal flasher relay which will require replacement.