I have a 93 4x4, recently I lost both my tail lights and license plate lights. I have checked fuses, bulbs, and ground. all other lights work what else should I try, could it be a relay etc.

 

Is it a pick-up? Check your wiring harnesses that run to the rear to see if maybe it has been comprimised in any way, and if you have a trailer pigtail, check those connections.

 

Check your fuses again, and use a volt meter to see if there good, sometimes a fuse can look good but be bad. Also make sure there is no corrosion on the fuses or the socket it plugs into. I had this happen on my 4Runner.

 

there is a wiring harness connector underneath the passenger side seat under the carpet, and if it becoms unplugged you'll lose your lights. Thats the first connection I'd check.

 

This happend to my 83 a while back it ended up being a bad taillight relay under the dash... its shaped like a small can and it has a 3 prong plug on it...

 

I wanted to update and ask for more advice on my tailight- license plate issue,come to find out, the last owner had put a 30 amp fuse in the fuse box instead of the 15 amp it calls for, I have had the truck for a year and had no idea it was there. when I pulled out the fuse it was still good, it had not blown the fuse, what it did was melt that fuse slot and the one above it. I put the correct 15 amp fuse back in but it doe not fit like it used to, its very obvious it shorted out or got way hot or something, what is strange is all the other lights that run off that fuse work, I have checked all bulbs grounds, fuses, switch on steering colum, wires running to tailights etc. im thinking that the bigger fuse than called for, in the fuse box fried a wire somewhere down the line in my harness or where ever. what would you try next? thanx Robert

 

You are correct. Rather than repair the problem, he just put a bigger fuse in it. I imagine that wherever the original problem was with the wiring has gotten worse due to arching and shorting. if you know you are not getting voltage to the tail lights, I would start chasing the tail lights wires and looking for a bad spot. Theres a good chance that you may be able to find it easier now since it has probably been arching/ melting at the bad spot due to the larger fuse.

As previously mentioned, trailer harnesses are always suspect.

Thats my 2 cents. Maybe some others can give you some good suggestions as well.

 

I found the bad wires on the harness, the spot was in the rear end right where the wires split going to each tail light. I unwraped the tape until I found the spot, two wires had completely melted apart, thank god it was in that spot the first spot I checked, I cant even imagine unwraping the whole wire harness until I found the bad spot. so word to the wise, never ever ever put a bigger fuse in the box than called for unless you want fried wires somewhere down the line. thanks for all your help

 

Nice job

 

Glad you got it figured out! Electrical problems can be a real pain in the arse

 

Good job man!