1993 940 wagon, non-turbo. After my third or fourth aftermarket radio was stolen, I decided not to replace it. This time the thieves were less destructive of the interior trim than usual, but I'm having electrical problems. The open-door warning beeper started coming on not just for the passenger door, but also the glovebox, and finally it came on permanently. I discovered that fuse 5 was blown, and replaced it, and the problem has gone away for now. But whatever caused the fuse to go remains a mystery. The wiring diagrams in my Chilton manual don't cover this.

Any ideas on the underlying problem? Or where I can find wiring diagrams for this model? (Why, oh why, did Haynes stop publishing manuals for newer Volvos?)