Troubleshooting Both Blinkers Coming on When Right Side Blinker is Activated

Question:

After installing the new plug end on my RV when I turn on the right blinker both lights on the RV blink. The left blinker is working correctly thanks for your assistance

asked by: Norm

Helpful Expert Reply:

In order to determine the problem, you'll need to use a circuit tester such as # PTW2993 to test the 4-way on your vehicle after disconnecting it from your trailer. Check the wiring going into your harness from your taillights to see if those are correct, if not then the issue is with the vehicle wiring. If the signals going to your harness are okay, you'll need to test the signals coming out of the harness, and if they are correct then your issue is going to be with the trailer side wiring.

Another likely culprit would be a poor ground, which can cause a host of potential problems, including your taillight problem. Ensure your grounds are secure and connected to a bare metal surface which is free of paint, dirt, or corrosion of any kind.

I've also linked an article on troubleshooting wiring for you to take a look at.

expert reply by: Kyle S