Trailer Lights Go Out When Headlights Are On

Updated 06/05/2019 | Published 06/04/2019

Question:

Weve troubleshooted as many ways as we can weave turn the headlights on weve tried brake lights is tried plugging in shaking out any dirt out of the actual wiring for the lights and weve got the hazard lights on in the truck right now which are causing the hazard lights to Blink but we dont have any brake lights on the trailer whatsoever or any other lights as soon as we turn on our front headlights is there any troubleshooting method you can get with us immediately would be greatly appreciated thank you

asked by: Meagan S

Expert Reply:

It sounds like you could have more than one issue on your trailer but the most prevalent is a weak ground or so it seems. I recommend that you start by checking both the trailer side and vehicle side connector, by check I mean you should remove each of them, sand down the surface and then reattach with new mounting hardware. A visual inspection of the ground terminal is not sufficient to check for function. I would also run a jumper wire on the ground circuit from each tail light up to the main trailer ground.

Please let me know if the issue still persists once all of the grounds have been checked and re-secured. I would also make sure the fuses inside the vehicle's fuse box are intact and you don't have any shorted/broken wires. I have attached a general trailer wiring help article for you as well.

expert reply by: Conner L