Troubleshooting Trailer Wiring that All Lights Turn On When Headlights are On

Question:

I recently purchased a trailer light kit for my 2008 saturn astra. My husband installed it and we seem to be having a problem. We the headlights are on the car it is giving direct power to the trailer lights and the brake lights and directionals on the trailer will not work. If we turn the headlights off then it works fine. Please advise if you have any ideas what is causing this

asked by: Dawn

Expert Reply:

It sounds like the running light circuit of your trailer wiring is shorting out to the other wires of the trailer harness that you installed so that when you have the head lights on the power from the running light circuit is also being applied to the other circuits as well.

I attached a couple help articles on troubleshooting for you to check out as well.

expert reply by: Jameson C