Right Side Trailer Turn Signal Blinks Faintly When Left Turn Signal is Activated

Question:

I get an arc when I touch the ground wire to my trailer light bolt to ground it. Is this normal? I went from no lights to good lights when I grounded to the trailer light bolt. It does seem to have a small blink on the right side when I have the left blinker on. All lights do work.

asked by: Gary

Helpful Expert Reply:

What you experienced is normal when working on a live circuit. It's best to have the trailer unplugged from the vehicle when installing lamps to prevent anything from being inadvertently shorted out.

If you're getting some bleed over into the other side when the left turn signal is operated, it means that you have a poor ground connection somewhere. The trailer lamps will either ground through their separate ground wire or via the mounting hardware if the lamp doesn't have a dedicated ground wire. If the lamp doesn't have a ground wire and is not attached to a metal surface that's in direct contact with the trailer frame, you'll need to run a jumper wire from the mounting hardware to the trailer frame.

You'll also want to check the main ground, usually located on the trailer tongue. Make sure the connection is secure, and not corroded. You can improve the connection by removing the ground screw, and sanding a dime sized area around the hole down to bare metal. Use a star washer between the ground screw and the trailer frame. When tightened, the washer will bite into the metal for a better connection. Give the completed connection a shot of rust inhibiting spray paint to protect from corrosion.

I've linked you to our trailer wiring troubleshooting guide which you might find helpful.

expert reply by: Mike L