7.5 Amp Fuse Blows on T-One Vehicle Wiring Harness for a 2015 Honda Pilot

Question:

I am using a 118265 wiring harness on my 2015 Honda Pilot. The 7.5 amp fuse has blown twice. After replacing it the second time the trailer lights only work if the headlight switch is in the auto mode. If I turn the headlights on in the manual mode I have no trailer lights. The wiring on the trailer checks out as being ok with no shorts. Any advise on how to correct this would be greatly appreciated.

asked by: Allen

Expert Reply:

There seems to be more than one issue that is occurring therefore it is going to be difficult to narrow down the problem you are having. I suspect both a ground issue which is causing the lights to work intermittently with the headlights and a short which is causing the fuse to blow. If you have access to a different trailer or tow vehicle then you can cut the time it will take to diagnose the problem down drastically.

I know you said you checked the trailer wiring but wiring issues are not always easy to find which means you will end up needing to check the same area multiple times. The 7.5 amp fuses you are blowing are tired into the stop/turn circuit. I recommend starting at each tail light and tracing the stop/turn wire back all the way to the trailer connector while checking for breaks. You will most likely need to remove the wire from the loom in order to see any visible breaks or frays. I also recommend removing the ground for both tail lights and the trailer connector, cleaning the surface with sandpaper if applicable, and then attaching with new hardware.

expert reply by: Conner L