Hey all, my 92 XJ makes a strange annoying buzzing noise everytime I press down on the brake pedal whether I'm at idle or driving. Brakes work fine and the ABS light doesn't come on after the initial start up check, but it's annoying having this buzzing noise come and go everytime I brake. I've checked all fuses and relays, everything seems ok. With the hood up and somebody pushing on the brake pedal, it seems to be coming from the passenger side, right by the firewall. Any advise?