Transmission control unit
I recently had my tranny serviced and it stopped the warning light from coming on and going into limp mode. I had the codes read and I don't recall what they were, but no tranny codes. One was a speed sensor code and mechanic told me that could be causing light. But has I read more could it be the TCU? Where is this unit on a 93 325is? What does it look like? Is it clearly visible, or do I have to remove items to get to it. I was going to try and clean the contacts if possible.