Hey Guys! I'm brand new to this forum, and I'm hoping I can get some help with my Audi. I have a 2005 A4 Quattro 3.0 . My car recently started having issues switching gears (mind you, I drive an automatic transmission) and eventually all of the lights on the gear selector(?) lit up, my check engine light came on, and now my car is in something I researched as "limp" mode? Basically it's stuck in 3rd gear so its super slow when I press on the gas and gradully speeds up but never leaves 3rd. Has anyone ever had this issue before? Can I fix it for cheap? I read that I might be able to fix it by replacing the transmission control module, but I'm not sure if this is correct. Thanks for your help!

 

i had the same issue with my 96 a4 the sunroof seal had leaked and made the carpet damp and moisture got to the tcm and it did pretty much the same thing yours is doing had the shift indicators all lit up and would not let it shift past second and also when shifting into gear it would shift hard,but however on the b6 cars i am not sure if the tcm is under the carpet on the passenger side or if it is inside the transmision but if you do find that it is under the carpet and you do find that its damp under there be sure to take a shop vac and get as much of that moisture out as possible or the replacment tcu wont last long at all and also make sure that the part numbers on the tcu match exactly you will find that there are several versions of a tcu for that car. i found ebay to be the best place to get those they range from 50-100 bucks but anyhow after i replaced my tcu the car shifted nice and smooth and the shift indicators were not all lit up anymore. hope this helps and welcome aboard!