cnotesdip

I started having this problem with the transmission its on limp mode and when i move the gear selector the car jumps its a hard hit when i move from parking to reverse or drive.

I hook it up the a diagnostic machine and i got the following 2 codes p1626 p1850 these codes are related its a missing message from the TCM, i source the TCM from eBay because the one the car had smelled burned i had water on my passenger side at one time, i try to adapt the TCM using a the launch scanner and it says error i try reseting the codes also and it comes back instantly.

I can shift without pressing the brake.

I don't know what to do, i was thinking about replacing the ECM next any ideas?

cnotesdip

is there any way to test the tcm?

Dana @ Ross-Tech

Those are Generic P code faults and very likely from the Engine, not the Transmission.

Do you have VCDS? http://www.ross-tech.com/index.html

http://www.ross-tech.com/vag-com/dtc-comparison.html

cnotesdip

this is the current code im getting 18034 17931 18014

cnotesdip

18034


P1626

Data-Bus Powertrain Missing Message from Transm.Contr.

18258


P1850

Data-Bus Powertrain Missing Message from Engine Contr.

Harddrive2000

I had a similar problem with my 2000 A4 2.8 V6 mid last year. Flood waters entered my car and soaked the carpet damaging the TCM (never knew the thing was under the carpet at the time). Had to drive home in limp mode. Like yours, car would jerk violently whenever i engaged D or R, and would also shift without the brakes on. Had to change out the TCM. The part number must be exactly the same from start to finish otherwise it will not work (thats assuming the replacement has no issues of its own). It took me a while to find mine. Initially tried one that had the same numbers but a different letter at the end. It did not work.
But the one that had the exact same numbers and letters worked instantly and my problem was solved.(Note: Both were used parts)

In my experience, the ECM is not the problem. It may simply be telling you that it does not recognize the replacement TCM, either because its not the right type, or because it has a fault.