Running Lights On Trailer Stay On After Truck Is Turned Off

Updated 08/20/2024 | Published 08/15/2024

Question:

I have a 2008 chef 3500 hd Silverado diesel that will not shut off running lights on a 2024 Texas Pride 22k gooseneck after all lights on truck shut off. Where should I look for problem. Had to pull trailer connector plug to shut off. I went around the truck on board brake control with a tekonsha brake controller from a 1994 1 ton Silverado. I dont see anything thing there that would cause this. Trailer manufacturer had me check fuse 22 trailer parking lights and it was good. Brake controller worked great while returning from Madisonville TX with trailer, only running lights wouldnt cut off

asked by: Timothy

Expert Reply:

Hello Timothy. There are many possible reasons why the running lights on your trailer stay on when your truck is off. The most common cause of this is a bad ground so double check to make sure your grounds are attached to completely bare metal surfaces and free of any paint, dirt or corrosion.

Another possible cause is if your trailer has LED lights they can stay lit dimly. This is not uncommon for some LED lights and the only solution for this is to unplug the trailer.

expert reply by: Jesse M

Tim G.

8/20/2024

Jesse, I found 12v power and running lights wires crossed in the male connector on brand new trailer. Plugged trailer into 2023 Dodge 3/4 ton tested with dodge auto trailer hookup test and everything checked out fine, turned off all truck lights and running lights still on. Pulled apart trailer plug and found running lights on +12 volt power blade! Reversed wires and everything okay!!! Thanks Tim