Are the taillights wired to the highbeam switch on a 1978 Ford F-150 Custom?
We don't have turn signals on our truck. Are the tail lights wired with the high beam switch? Does the high beam switch have to be grounded?
maybe this will schematic for us~
You have a 35 year old truck. Let me ask, did the tail lights ever work as they suppose to? Did you just acquire the truck? Vintage vehicles use to have replaceable flashers associated with the turn signals. Your's may be out. With the key on, manually move the signal arm up and down. If the tail lights switch on and off the flasher is shot.
Yea they worked perfectly before we switched out the beds. I had a shortbox step side originally but I went to the junkyard and picked up a regular shortbox that was on an other 78 f150. When I get home I realized that the wiring harness had a broken wire inside it. And then I figured out the box was off a 67 f150and that had a diffdifferent wiring. So I got it figured out eventually, I had to run about three more grounds and rewire it completely. It was a pain but now I got it. That diagram really helped.