Taillight Grounding

These kind (original I think) ground from the case/housing, correct? Trying to track down why one isn’t working.

 

In addition to the ground wire between body and frame under the hood, I added one near the rear fuel tank, too.

 

Well, a week of pb blaster soaking wasn’t enough to stop me from breaking off the studs. I guess I’ll drill them out now and replace with new hardware which should solve the grounding.

 

I put these on mine...just an idea...these have a plastic housing with dedicated ground wire.
Round 4" Truck / Trailer Stop, Turn, Tail Lights with License Plate Light | Super Bright LEDs

 

Because... "they ground from the casing." A common issue.

Installing with a dedicated ground wire may be worth considering.

Also thorough cleaning and corrosion protection of all contacts and connecting surfaces for the bulbs.

 

Your original lights are Hall 701 lights. Those broken stud (they almost always break) are 1/4-20 carriage bolts that have the square shoulder staked in the housing. With a few taps of a hammer (backing up the housing on a vise), the broken bolts drop out. You can find replacement carriage bolts, even in stainless, pretty easily. Replace them and stake the square shoulder with a pin punch.
The stainless bolts don’t seem to ground as well as steel, but still are preferred by me. Just be sure to use a sharp star washer under the fastening nut to aid in grounding.
Whatever you do, don’t toss those original lights! I’m still looking for those, even if they are not chrome.
-Donny

 

Thanks for the hints. I got the studs out and you are right 1/4” carriage bolts. I did a test fit and it was a grounding problem and light works now. The spacer thing between the body and light housing was 1/2 full of dreck. Cleaned them up and painting them before I reinstall.

 

I like running a dedicated ground wire to things, and then meet at a common ground stud that has a single thicker wire going to the battery.

 

That spacer thing is used only on the left side, and only the left tail light has a window, glass(early) or plastic(late). That spacer moves the light out so it can light the license plate.
-Donny

 

I run a Green ground wire to the rear of my Jeep for my trailer hitch and tail light's just to make sure they are grounded.

 

Run a ground wire to one of the anchoring bolts/studs of the light. Fasten the other end to frame or tub.