Hi folks. We've just bought a C5 A6 4.2 Quattro. We bought it knowing it had a gearbox fault which would see the car go to into gearbox limp mode after a couple of miles.

I've done a lot of reading and heard that it's usually a case of needing a gearbox rebuild or a wet TCM.

We got the fault codes read, and it came back as faulty control module. Pleased with that, I took out the TCM to inspect it. While it is damp under the carpet, the TCM was bone dry.

II need to find a replacement, but all the ones I've seen on ebay are the same part number but with different letters on the end. What do the letters signify? Can any TCMs be substituted? My car has a TCM with 4B0927156CH printed on it.

Thanks all!

 

Hello?

Anybody out there??