Troubleshooting Trailer Tail Light Right Turn Signal Not Working

Question:

My trailer plug is not getting power to the right turn signal. Brake lights and left blinker work but not right blinker

asked by: Jake

Expert Reply:

Since you have all light functions except for the right turn signal, the issue is most likely a bad ground. Your brake light on that right side will be on the same wire as the turn signal, so that wire is allowing enough power to overcome the bad ground for the brake light yet the blinking signal is strong enough to overcome that bad ground.

I recommend using a circuit tester like # PTW2993 to test your signals coming from your vehicle when not connected to the trailer first. Then clean those connections on both sides and reconnect the trailer. Next check the main ground connection to your trailer frame to make sure it is bare metal to metal and free of corrosion or debris. Next check the ground at that right tail light as often there isn't a separate ground wire and the ground is through the mounting hardware. If there is a separate wire, clean that connection with some sand paper, and if not clean the mounting hardware connection to the frame in the same way. If that doesn't solve your issue, check your bulb to see if you have a dual filament bulb that is bad.

expert reply by: Jason S