Could use some sage advice troubleshooting a very weird problem that seems to be associated with my ABS system and is making transmission malfunction. My mechanic is stumped.
My car is 318ti Automatic manufactured 3/96 USA
What happened: Transmission Light came on. ABS light
not on...
Transmission went into "safe" mode (3rd gear I think?)
Took to a place that specializes in BMW transmissions - highly recommended.
Transmission OK. They discovered (and said they've seen before) the ABS control module is malfunctioning, and since the ABS uses the transmission to control the traction system, it can make the transmission malfunction. Recommended disconnecting ABS module, which indeed works, but now I have no ABS, of course. They want $1200 to fix it.
Curent status: ABS modules disconnected (The transmission place and my mechanic both said this would not damage the car in any way.)
"ABS" light
on.
"Check Engine" light
on (presumably because it knows the ABS module is not connected)
Transmission light
out and car shifting/ driving normally for 300+ miles.
But I can't pass inspection without ABS so need to fix.
Plus winter's here and ABS would be nice. The inspection station said I had some kind of "timeout error"??
I got a used ABS module and replaced it and the lights all went out and seemed fine. Cool!!
Drove about a 3 miles, going up a hill, the car shifted into 3rd gear and the transmission light came back on. Owner assures me the module was working in car it was pulled from. Well it was for me for a few miles. (Does it need to be reprogrammed or something?)
So... ABS disconnected (again), transmission fine. ABS module connected, transmission funky. Any ideas? Thanks.
Help Troubleshooting ABS / Transmission Problem 
Linear Mode
