No Brake Lights on Horse Trailer but Running Lights Work

Question:

On my horse trailer I have all the lights hooked up the lights do not come on when I step on the break my running lights work what is the problem

asked by: Jay

Expert Reply:

Do the turn signals on the trailer light up when you activate them in the tow vehicle? If not then I suspect you have a few blown fuses in the tow vehicle. If you can provide me with the year, make, and model I would be glad to let you know which ones you should check. If the fuses are all good, have you checked the brake/turn light bulbs on the trailer to make sure they are not blown? This would be your next course of action.

If the light bulbs and fuses are good then I would test the turn/brake signal pin on the vehicle side trailer connector with a circuit tester while the respective signal is active. If no power is present then you will need to trace the wire(s) back while checking for breaks. I would also repeat these steps on the trailer side trailer connector but you will need to use a 12 volt battery instead of a circuit tester. If you have access to a different trailer/tow vehicle you can save yourself some time as that would allow you to determine if the fault is on the vehicle or trailer.

expert reply by: Conner L