I just got a '72 f-100 and my brake, back up & turn signals are not working. I checked the fuses and replaced the flasher. The headlights, running lights & hazards work fine. any suggestions ?

 

grounds

check all your ground points--where the tailight bezels contact the truck body.

Or, do what I did after I got sick and tired of constantly dink'n with them.

I drilled a pair of small holes into the tailight bezels (the metal/plastic part that holds the bulbs themselves) . I also drilled a small hole in the bed/box behind where the tailights are installed. Done right, this hole could be put anywhere and never seen or noticed.

I then cut a 10 inch lengh of wire, stripped the last half inch of sheilding off each end. Using a self taping screw I secured one end of the wire to the tailight bezel, and the other end I screwed to the hole I made in the body/frame/box...wherever you put your 2nd hole.

Reinstall your bulbs, re-connect your wire harness, and test your work. In my case my problem was solved. I had already repalced the original rotted wire harness from the engine bay all the way to the rear lights. But my tailight grounds were still not up to par. My rear lights refused to work. I know I had not missed any proper OEM ground circuits when I changed the full harness. It just turned out that due to ages of rust and grime, the original ground points were still junk, and prone to failure.

 

With further research I think it might be the turn signal switch. They have a repair prt @ O'Riellys for $16, I am going to pull it apart tomorrow and hope that's it. I will post pics it is a nice straight '72 sport that runs great. I have been looking for almost a year for the right one. If anyone has experience with this I would appreciate it. Thanks for the help I am sure I will be on here often.

 

I thought it might be my signal switch as well, or at least the plastic parts inside. but when I took mine apart to check it out, it was fine. (like you, I've replaced the flahsers, and bulbs, and even the harnesses...)

taking the wheel off to get to the switch wasn't so bad. push down on the horn button, and turn it a smidge left or right and it pops off. don't force it to turn!! you could snap of the retainer parts and then it's more of an adventure to put back together.

loosen the center retainer nut until it's flush with the top of the "bolt" in the center of the steering wheel. then install some sort of puller and the steering wheel pops off pretty quick.

with the wheel off, the TSS is pretty much easy to get to. **the Turn signal lever screws into the TSS assembly-- you don't want to just grab it, and rip it out--you'd do more harm than good ;-)

I might get hung out to rot for this next bit...but here's a link to the fun I had with my tailights. this thread is on another Ford trucks forum tho...

http://www.fordification.com/forum/v...hp?f=8&t=51291

many apologies to the forum gods here if this breaks any taboo stuff. :-)

 

There should be a 3 wire factory connection near the end of the passenger side chassis rail. Find it, separate it and test the side from the front to see if the wires are hot.

Your truck may have to have the switch on for the turn signal & brake to power up. There are only 3 wires, the brake & turn signal share the same wire.




John

 

Could most likely be the turn switch. I had a similar issue when replacing the shift collar I had to cut the turn switch harness and splice all the connection on the install. One of the connections was not making proper contact resulting in identical situation as yours. Still don't understand why the brake light line is routed through the steering.