Trailer Turn Signal and Brake Lights Not Working But Running Lights Work
Question:
Hello, I have checked and verified the connector and all the lights are working on my suv. And that the running light on the trailer also works. However, neither the signal nor the brake lights are working. I checked the pin on the trailers connector and noticed only the reverse and running light works I checked it with the circuit tester. Ive also checked and clean to makes sure it has good grounding from both tail lights to the trailers frame are free of corrosion. Note: The 12+power from my suv is not working which I dont think it has any effect on my issues signal and brake lights for I do not have any needs of it on the trailer. I am towing a boat and it does not requires any charging etc. I am running out of ideas or where to troubleshoot to determine the cause of my signals light. Will you help?
asked by: Matt N
Expert Reply:
If you are getting power on the brake light/turn signals circuits on the vehicle side connector but not on the trailer side, behind its connector, when plugged into the vehicle then the issue is with the trailer's connector and it will need to be replaced. I have included a link to the trailer side connectors that we carry.
The connector could have been damaged or has corrosion internally that cannot be seen. Replacing the connector would fix that problem.
If there is power behind the trailer side connector when there should be then the problem is further back. Check for pinched or damaged wires and repair as needed. You may need to test the wires in several places front to back to locate where the dead spot is.
The worse case scenario is replacing the left and right turn signal/brake light wires from the connector back.
If power is getting all the way back to the lights but they will just not light up then it is either a bad ground or something wrong inside the lights. Running a jumper ground from the lights to the main trailer connector ground could help. And if the lights are having internal problems you can replace them. I have linked the tail lights we carry as well.
