Trailer Right Turn Signal Does Not Work on a Trailer Towed by a 2010 Toyota RAV4

Updated 11/15/2012 | Published 11/14/2012

Products Featured in This Question

Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

(286)

$58.38

Hook Probe Circuit Tester

(65)

$13.35

Question:

I just ordered and installed a wiring harness on toyota 2010 rav4 and the right turn signal on car works but not on the trailler - whats up. The trailer lights are good as the trailer lights work on my buddies 2010 rav 4 just fine.

asked by: Ken

Expert Reply:

If it is only the right turn signal that is not working this sounds like ground problem. The ground on the vehicle side that grounds the converter box may need to be moved. Try moving the ground to see if that solves the problem. If not, use a circuit tester like # PTW2993 if needed to test the pins in the connector without the trailer connected.

If the right turn signal works on the 4-Way then the issue is on the trailer. If it does not work then test the green wire that goes into the converter. If it works but the output side does not that indicates a bad converter and it will need to be replaced.

If the input side green wire does not work then that indicates a problem with the vehicle wiring. You may need to check some turn signal fuses to see if that is the issue.

If everything checks out on the vehicle then move on to the trailer. Make sure the main trailer connector ground is attached to a clean and corrosion free bare metal surface. Then make sure the right side light ground is also free of corrosion.

If you have a tilt trailer or folding tongue, run a jumper ground from the light grounding location to the main trailer connector ground. Trailers can be finicky meaning they might play nice with one vehicle but not another. Even so you will want to troubleshoot the converter on your RAV4. I have linked a video that will help.

expert reply by: Michael H