My Audi is in "limp mode" and won't shift into 5th gear.
I have a 1999 Audi A4 1.8T Quattro. It all started with the car not shifting into 5th gear and the PRND being all lit up(what I have heard them call limp mode). At the same time my ABS light was on and my reverse lights would stay on in drive.
We first started by replacing the Multi-function Switch. That fixed the reverse light problem, but nothing else. Then, we decided to have our ABS Module rebuilt in hopes that it would fix all other problems. When we put the rebuilt one back in the ABS starting working again and the light went out.
Now we are out of ideas as to why the car is still in "limp mode" and won't shift into 5th gear. So we took the car to the Audi dealer and basically they said that the Multi-function Switch we had replaced must be faulty and that we need to replace it again. Does anyone have any ideas where we can go from here. Our mechanic (who is also a friend) is pretty darn sure it's not the Multi-function Switch. Any help would be greatly appreciated!
You'll need a scan tool that reads Audi proprietary codes, not just OBD-II. But here's one quick...
Disconnect wiring harness connector to multi-function switch at left front side of tranny and thouroughly clean contacts with electronics cleaner. Closely examine contacts and ensure they are not corroded.
Beyond that, you'll need a VAG-COM or equivalent to check ATF level, read TCM codes, or run tranny diagnostics.