I just bought a 1989 535im (see my other post) and I am having a strange problem with the check control and trip odometer. Every time I shut my car off and restart it, the trip odometer will reset itself to zero. I have had the car since late yesterday and just a little while ago the check control display was in german at start-up and stayed in german until I shut the car off and restarted it, then it went back to the english-us setting. The previous owner said he replaced the battery pretty much right before I got the car. Could this cause what I'm experiencing, is there a hook-up around the battery somewhere that he might not have plugged back in that could cause this. Also the OBC works fine and keeps it's info. Is there anyone who has experienced this problem that can shed some light on it?