2005 Audi A6 car can't decide what gear to be in

DVIRSA

MEMBER
2005 AUDI A6
6 CYL
4WD
AUTOMATIC
50,000 MILES

I have a 2005 A6 2.4L that is having a problem with the transmission. It seems that the car can't decide what gear to be in.

The phenomenon: while driving using automatic gear (D) sometimes the gear indication showing that the transmission is changing gears from (D) to (S) and vise versa several times. Most of the time it become free and I can go on, once I had to stop over and restart the car.

It started after I took the car to a clean shop where they cleaned also the carpets (when I took the car back the front and rear carpets were a little bit wet).

I took the car to an authorized VAG service and they told me that the Gearbox computer should be replaced, as you probably know this is very expensive part and I would like to know if there is something else that I should check before changing the computer?

My questions are:

Did anyone face such phenomenon?
Are there any commuter codes which can indicate TCU failure?
Is there anything else which I can check?

Thanks in advance
Dvir Salomon
Israel

B.T.W – sorry for my language

1 Reply

KHLOW2008

MECHANIC
41,814 POSTS

Hi Dvir Salomon,

Such problem might give you a lot of recorded errors and would not be accurate to do repairs.

I would suggest checking the PCM wire harness connectors. Water vapour causes condensation which contaminates the connectors and provides insufficient/bad connections.

Cleaning with contact cleaners and drying up the connectors ought solve the problem if it is not too late, just worried there might already be corrosion of the circuits which had caused shortings.