Everything But Running Lights on RV are Working  

Question:

Expert Reply:

If everything except the rear running lights on your RV are working, I first recommend testing to see whether the issue is coming from the tow vehicle or RV side wiring. You can use a circuit tester like # PTW2993 to test the pins on your vehicle side connector with the trailer disconnected. Check to see if there is any signal with the running light pin location.

If there is no signal on this pin, you will want to check for a loose ground (white) wire or for any damaged or worn areas on the running light wire and just apply electrical tape as needed. Also check to make sure there is not a missing or blown fuse in the power distribution box under the vehicle hood.

If the signal on the running light pin is good, then the issue is most likely in the RV wiring. You can test the trailer with a spare battery to see if the running lights work. Then check the ground wire and running light wire on the trailer from the connector and back to the rear lights. Fix any damaged or worn areas as needed. Check all of the ground connections, including the main trailer ground, and make sure they are attached to clean bare metal spots on the trailer frame.

Lastly, I recommend checking both the vehicle side and RV side connectors for any dirt or corrosion that may be preventing a clean connection.

If you are unable to locate or resolve the issue, please let me know and I will be happy to look into this further. I have also attached an article on troubleshooting wiring that you may find helpful.

expert reply by: Chris R

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