Why are My Trailer Lights Not Working Properly?

Question:

If the all the brake, signal, running lights outside work and the trailer and interior light flash at times. Do I need to replace the small battery even thought the trailer hook up and truck running? How long dose a small batter last? I’m thinking I have a short or small battery needs to be replace. Have electric jack hook up and it’s not running but the led light flashes very dim as well on the unit. I had the jack over a year, maybe it needs to be replace. I might have two issues going. One minute the jack work the next it’s dead.

asked by: Edward D

Expert Reply:

The small battery is actually used to power a break away system, like the Hopkins Engager Push-To-Test Trailer Breakaway Kit # 20099, or electric jack like the etrailer.com Electric Jack w/ Footplate # EJ-3520-BBX, but should not be affecting the lights in the trailer.

What sounds like is happening is a bad ground. I would check all your ground connections making sure they are not corroded or disconnected. A bad ground can cause all sorts of weird things to happen.

It also doesn't hurt to check the ports on the vehicle's plug, but odds are you have a bad ground.

expert reply by: Lazer S