I have looked and have found a few posts with similar issues but they are older cars and there was really no conclusion as to what the problem ended up being. The number 4 fuse in my '97 E420 controls the turn signals and the reverse lamps. When there is a good fuse, I can start the car, shift quickly past reverse and into drive and everything is fine. The turn signals work and I get no error messages. If I shift into reverse and leave it there for more than about a second the fuse blows out and I get the bulb failure message. Of course the reverse lamps and turn signals won't work because the fuse is blown. I am gathering that there has to be a short somewhere in the system. I tried taking the bulbs out of the reverse sockets, but the fuse still blows. I tried pulling away as much carpet as I could and looked at the wiring and can't find any problems in the wiring (there is quite a bit of wire that is not acessable with out major dissasembly). I have heard about people having problems with their neutral safety switch, but it seems like they don't have an issue blowing fuses. If anyone can help I would appreciate it.