Being that only your brake light is working, I would suspect one of two things. Either the voltage regulator went bad and blew all of your bulbs at high RPM (all but the brake light because its not on at high RPM). Or more likely that you have a bad key switch. The key switch has three positions, off, on w/lights, and on with out lights. First make sure that the key is in the correct postion. Then you can either try another switch, or jumper the RED/YELLOW wire to the YELLOW/RED wire on the back of the switch.