VKB, look down in the left hand side foot well area inside the cabin. You will need to remove the plastic trim there, but the computer is behind there. If you are getting water in there, you have a plug that has been dislodged and is allowing water to get into the cabin. I would get in there, see what sort of issues you may find and then seal everything up really good. I would also recommend pulling the left front tire and then pulling the wheel liner out and see what you can from the outside of the car. Odds are, whatever your problem is, it will be fairly obvious.

 

Check for moisture behind the LH A-post trim as well. More than likely the windscreen is leaking (may have been replaced at one point?) This is the only way I have seen water ingress that affected the TCM.

 

uh, if you dont know where the TCM is, how do you know youre getting water in it?????