My wagon wouldn't shift and I had to use the shiftlock override button to shift. I checked the brakelight switch and it was ok. The fuse was not shot either. After taking the shifter cover off I found the problem to be that the little triangle shaped plate to the right of the shifter which contains the copper contacts that slide was corroded a bit and not making good enough contact to unlock the shifter. I took it out, removed the metal plate and removed the little plastic arm inside. I then bent the contacts on the plastic arm out and sanded the copper tips as well as the copper slide plates. I then greased it with fresh grease and re-assembled. It did not work at all after I reassembled and I was pretty hacked off. It didn't work because during re-assembly I popped the 8 amp fuse to it. A new fuse and it works like a charm. Hope this helps!