Tail Light Wont Come On
 

My passenger side tail light is having some issues. My turn signal and my brake light will come on but my tail light wont come on. The three wires connected to the socket look fine and so does the socket so I am not sure what the problem could be. Any suggestions?

The bulb has dual filaments. One is for the turn signal/brake light, the other is for the driving light. You need a new bulb. Possibly you are not getting power to the wire that feeds the driving light, but it's probably just a bad bulb.

Check the wiring a few feet away from the taillight. I think the wiring can get close to the exhaust and melt if the wiring has some slack.

+1 on the new bulb for starters its a easy start.

Swap with the reverse light bulb and recheck.

When asking any question in the future include YEAR and MODEL, year and model, Year and Model. Yeah we get it, you're talking about an H3, but they are not all the same and there are different models that indicate which has what.

How old are these trucks? How long does it take for corrosion to degrade electrical connections? Get some CRC Electronic Cleaner, and use it every time you check any connection, replace a bulb, or have an issue.

https://cimg7.ibsrv.net/gimg/www.hum...b056b4f288.jpg

Have you checked the trailer harness behind the rear bumper? There is an issue where the frame chafes the harness.

Good point. My 07 had that problem, wire harness was too tight rubbing on the chassis under the back door above the bumper and shorted out, but my tail lights always worked, just killed the battery a few times. Probably a matter of which wire gets exposed as to where the problem shows up.

I ended up pulling the trailer lights fuse years ago to make sure dont get caught with tail light on and did my best to rubber insulate the wiring from the frame (rubber old shoe pcs and electrical tape with fingers (it’s tight up thereI Never identified exactly where if there was a wire break but the fuse out ensures ok - no dead battery. It’s scary....

I just need to remember to put back in if towing

Ive changed the bulb and checked the fuse.