Trailer Lights

[harmanoff]

This isn't about a boat trailer but its the same concept anyway. My father and I are rebuilding a 16 flat bed trailer for hauling our tractor to and from deer camp, rock, and any other misc things. We wired up the new waterproof LED trailer light kit I got the other day, his truck the break lights, blinkers work, running lights do not, my truck nothing worked. We hooked the ground and running lights wire straight to a battery and all the lights come on and work, so im assuming a ground issue somewhere. Any ideas where to start on the truck for the ground issue?

 

[Thirsty Endgrain]

Are you testing your trailer lights at the 4 pin plug itself? And have you tested the truck 4 pin plug? For the truck side a simple test light, or for the trailer side, a battery is all you need. Use the ground on the 4 pin plug in both cases, that will tell you if any of the issue is ground. If the truck light output works for brakes and blinkers but not running, then trace the running light wire. On yours it's likelier ground, since nothing works.

There's no substitution for getting down and dirty and tracing wires, and trailer/tow vehicle wiring is notorious for issues. Many times it's been done by not the highest level of DIY'er.

 

[dingbat]

This isn't about a boat trailer but its the same concept anyway. My father and I are rebuilding a 16 flat bed trailer for hauling our tractor to and from deer camp, rock, and any other misc things. We wired up the new waterproof LED trailer light kit I got the other day, his truck the break lights, blinkers work, running lights do not, my truck nothing worked. We hooked the ground and running lights wire straight to a battery and all the lights come on and work, so im assuming a ground issue somewhere. Any ideas where to start on the truck for the ground issue?

What year, make and model of your truck?
Factory tow package?
Harness connected?
Fuses installed?
Know issues with some models with led lighting

 

[harmanoff]

The trailer lights work when hooked to a battery, i haven't checked fuses yet, that is the next step just haven't had time. I will attempt to hook it up to the battery and use the ground on the truck its a 2011 F150 Lariat factory tow package

 

[briangcc]

Dad's truck - are you sure the running lights work on the truck? Having btdt with a Tundra, a blown fuse could be causing your issues. I'd also check the 4 pin at the truck to see that it's passing power.

As for your truck - sounds like the wiring harness on the truck isn't passing anything. Have you checked the output on the 4 pin connector to confirm its actually passing power? Either that or its wired incorrectly.

 

[harmanoff]

not yet, been super busy, the last thing i pulled with my truck was my camper, lights worked fine for it.