In Reply to: Re: 92 Wagon Rear Window posted by Mark Lane ('92 525iTA) on September 19, 1999 at 21:35:22:
The problem are the wire harnesses running to the tail gate. There's one on the left and one on the right. They get caught between the hinges and the bodywork and after months/years some wires finally get cut and will short, especially when wet after rain or carwash. This results (depending on which wire is cut) in problems like tailgates no longer opening, light problems, rear screen wiper no longer returning to rest position, etc. You can try to repair the damaged wires but the harness will become thicker due to butt splicing or soldering so the problem will return. I replaced both wire harnesses on my car (about $250) and made sure they wouldn't get damaged again by slightly twisting them. When the tail gate comes down they move out of the way.
According to my dealer this is common problem that will happen to all of the Touring models.
Good luck. Luc.