I drive a 2004 Audi A4 1.8T CVT and recently my MIL (check engine light) came on. I went to the Audi dealer and they ran a diagnostic and they said I needed to replace my Transmission Control Module (TCM) and it would cost $2500 to replace it.

I got a copy of the diagnostic from them and the fault reads: "18201 P1793 Output Speed Sensor 2 ciruit No signal." The funny thing is that when I borrowed my friend's OBDII reader there was no faults registered and because there is no faults registered I can't clear the MIL (Engine Check) light.

Do you think I really need to pay $2500 and replace the TCM ?


Thanks for reading and any advice you can offer is greatly appreciated.

Gary

 

Gary -

I had similar problems. Try to get an indy to give you a quote. TCM's go bad on CVTs. Search the forums for TCM and you'll find a bunch of threads going over the issue. Best of luck.

 

Guys,
I had the same problem with my 2003 audi A4, after a lot of stressing and researching the only way to fix this problem is to actually replace TCM. The part it self cost $1.350, oil and gasket and labor were another $1000, just got the car back, problem was completely gone..Had the problem with TCM, blinking light in the dash in the gear box, didn't want to go reverse, check engine, etc..You have to replace it, there is no other way..

Hope this helped,
Nick