It sounds like you have a dead short on a wire to the high beams, the wiring should be protected by the circuit breaker inside the light switch, the problem is you will have to physically check the wiring, it could be pinched, or the insulation gone, I would start where the switch is to turn on the high beams, if its under the carpet, you need to pull up that corner and check it out, and trace the wires out. You didn't say what year and car you had. Good Luck.