i have a 2002 tacoma and i just replaced the rear lights to a trailer. before with the old ones in everything worked ok with the left rear brake light. Now i cant get anything out of it with the new lights. i took the wires and hitched them up to the other brake light and it worked fine (using its same ground not the other one). Also i have a license plate light that runs from the same power as that left brake light and it works fine. Tried unhitching that plate light and still did not work. any suggestions? i have a 4 flat.
thanks

 

Do you have a test light? If not, buy a little cheap one that you stab into the wire, and has a clip on the other end for ground. $5.00 That way you can check to see if it's your wiring at the plug on your truck, trailer, light bulb wiring. Second, and this is just my opinion, I would replace your flat 4 with a 7 way RV style plug. These are what most trailers are using now. I have trailer brakes on my boat trailer that would not work with the flat 4 setup that Toyota supplies us with. These plugs can be purchased at Walmart very cheap. $15.00 They are very reliable, and if you ever tow something that has brakes or needs aux. power you'll be set up. I was actually able to use an adapter to the flat 4 and just run an extra couple wires for the extra connections. That way I didn't even have to butcher my harness in the back. Totally worth it!