Hello, I have a 1966 F100 and the brake lights aren't working. The lights work when i turn on my lights, but brakes no, turn signal left stays on, right doesn't work. I was guessing wiring and didn't see anything that looked loose. Brakes were just redone all the way through with a new brake cylinder. i am thinking of replacing my Turn Signal Switch as that would help possibly with the signals, but wanted to get any thoughts or suggestions.

 

First thought would be , did the brake light switch on the master cylinder get plugged in? If you ground the wire that goes to the switch and the lights come on then the switch is bad

 

In an addition to rp67F100's reply. Remove both wires from the stoplight switch and join wires together with something, say cotter pin. Make sure your sig lite switch is off. See if brake light come on, and try with key on. Visibly look at the filaments in the stop and tail bulbs to see if one is broken and laying against the other filament. Let us know how you make out as there are other things to look at. Cap

 

thanks everyone for the help on this and i am getting close. i am replacing my turn signal and all the wires match up except 2 for the 2 prong connector. it mentions cable colors have changed. my current has Orange/Blue & Green/Orange...the two left over cables to plug in are Yellow/Black & Red/Black. any insight to which one goes where?

 

For me, n. ot easy to tell you where the none matching wires go. Are you sure your replacement sig switch covers 1966? You are definite your original switch is bad?? Best suggestion, do online search for Ford wiring diagrams, up or down from 1966 looking for a year that uses your mismatched wires to see where they go.