Troubleshooting Trailer Light Blinkers Not Functioning with Headlights on 2012 Honda Pilot

Question:

Im responding to the same question that Mark had in which Bob responded about trouble with trailer lights. I replaced all the wiring to the homemade utility trailer I bought recently including a new 4 pin connector. After some trial and error, I found I needed ground wires to both lights on the trailer to make the brake and tail lights to work but NOTHING helps with the turn signals. Ive tried even putting a short wire to a light bulb at the vehicle 2012 Honda Pilot and I get a light, but it will not blink off and on when the signals are activated for the Pilot. Im at my wits end trying to figure this out. Any suggestions?

asked by: Mike

Expert Reply:

First we need to determine if the problem is on your vehicle or your trailer. To do this use a circuit tester like part # PTW2993 to test your trailer connector for voltage in the correct places when the taillight functions are applied. To see how this would be done check out the video I attached.

If the voltage check out there then you know the problem is on the trailer, if not then the problem is the tow vehicle.

Since the question you referenced was that the taillights didn't work when the headlights of the tow vehicle were on you will want to do the test I mentioned with the headlights on.

I still suspect that the problem you are experiencing is ground related. You may have to run the grounds of each light assembly back to the main ground wire of the trailer connector you installed. This would be especially true if you have an aluminum trailer.

I attached an FAQ on troubleshooting 4-way installs for you to check out as well.

expert reply by: Jameson C