i have a 70 mach 1. The brake lights, hazards lights, and turn signals quit working. Fuse is good. Headlight and tail lights are working. I replaced the turn signal, hazard light switch. This is where it gets good. The new switch in, the brake lights are always on. Still no turn signals, hazard lights will come on but no flash. Any ideas? Is it possible the new switch is bad?

 

Did you replace one flasher unit or Two?

It sounds like there is a grounding problem and the circuit is trying to find another way to complete itself.

If you have a multi tester I would start with that and check the harness connections beginning with the column and work your way out from there towards the lights.

 

i have 12v coming from the brake light switch to the turn signal switch at all times. i think that i should only have voltage when the brake pedal is pressed. if that is correct then i also have a bad brake light switch.