What wire gauge is used for tail lights?
 

I'm not sure if this is the right place for this question, but I want to rewire my tail lights. My passenger side tail light doesn't work with the driving lights on. It works when I apply the brakes or the signal. I changed the bulbs and still nothing. I'm not sure what gauge of wire to use. I think it's somewhere between 22 - 16 stranded copper wire. Anyone know the answer? I'm planning on buying a spool of the wire and building my own wiring harnesses for the tail lights.

Don't go any smaller than 16 guage. 14 would be better. But, most auto parts stores sell three-wire accessory wire, which is a roll of three wires joined next to each other, but in a different color insulation (think speaker wire, but with three wires instead of two). It's used alot for wiring trailers. if you live near an RV dealer, they would have it to. Something like that would be a much better choice than stringing several single wires together. Neater, too.

Take care,
-Chris

I decided to "work" with the original wires and I made it worse. I cut out the "melted" connector and matched the colored wires to each other using bullet connectors. (GRN to GRN, BRN to BRN, BLK-PNK to BLK-PNK, etc.) There were two (thick) BLK wires connected together. Should these two wires go together? I'm asking because now my headlights and tail lights work. When they are on when you signal, the passenger side signal lights up both the tail light and reverse light. I think the two BLK wires are screwing me up. Anyone know what's wrong?

The black wire is the ground, and all of the light circuits are spliced into it. The problem is that you have another spot somewhere where the reverse light wire (black/pink) is melted to the passenger side turn signal wire (orange/light blue).

Take care,
-Chris

Thanks Chris, I took another look at the wiring harness and learned a lot. (I'm an idiot when it comes to this stuff. I passed my Electrical shop class in high school, but never used my "new knowledge" on anything.) There are five wires coming from the Tail light/Back up light assembly. Under the car, there's a connector that connects "four" wires into the "five". The connector fell apart in my hands when I tried to find out what the problem was. I went to Auto Zone, Pep Boys, a Junk yard and even my local Ford dealership and learned this is a rare connector. Saturday, I'm going to a "Pull it yourself & save" used parts yard and hopefully I find what I'm looking for.