I’m restoring my 75’ F100. I have replaced the wiring harness with a new Kwik Wire 14 circuit one. I cannot get my brake lights or hazards to work. The turn signals and tail lights work great. I have checked the brake switch with multimeter and it checks out good(the brake lights did work before also). I have checked the fuses, it’s a new fuse box. I have power to one side of the switch connector. I took a paper clip and jumped the connector and still no brake lights. I think the brake and hazards are together as I understand it. I’m pulling out the little hair I have left. Anyone have any ideas? Thanks.

 

Welcome to FTZ! Remember your brake/stop lights go THRU your signal light switch. If you altered the connector adjacent to the steering column just under the dash or didn't feed it properly with your new wiring harness, there may be your problem. Cap.

 

Unlikely, but... If you have cruise, there may be two brake light switches. My '76 had that, a second, redundant switch, for safety.