Brake Light Nightmare

[supraheelfan]

The lamp failure box has already been bypassed by the previous owner. All the lights work on the car except the stop lights. The taillights, turn signals, hazards, reverse lights, and the license plate lights also work. What to do?? Any suggestions will be appreciated. Thanks.

P.S. I might also need a copy of the wiring diagram, because every single one I get doesn't seem to help.