running lights won't work on passenger side traile

[The motor guy]

I bought a new utility trailer and the truck apparently had a blown fuse for the running lights, well I replaced it and all the running lights work except the passenger side. It's a dual filament bulb 1157 and also has a 168 marker light. I changed bulbs, no luck. The brake light filament lights up on the bulb but not the running light filament. Is there two wires for the dual filament bulb? Plus another wire for the marker light? Here is what it has. Trailer is brand new. Probably will put LED lights on once I figure out this problem.

http://www.go2marine.com/product/384745F...tml?WT.mc_id=b1

 

[Rand]

almost always trailer wiring issues are bad ground since they are using the metal chassis as a common ground.

Usually the first thing I do is run ground wires.

 

[eljefino]

I bet you blew the fuse when you plugged the trailer in. Probably has a pinched wire that sometimes shorts to ground. The parking light fuse also runs your dash lights and you'd know they were out.

The parking light feed (brown?) runs down both sides of the trailer, so it probably splits near the connector. Run down the frame looking for trouble. Or bang around the neighborhood to see if it blows another fuse.

 

[eljefino]

Originally Posted By: Rand
almost always trailer wiring issues are bad ground since they are using the metal chassis as a common ground.

Usually the first thing I do is run ground wires.


The 4 pin connector has a ground. If it goes kablooey you can still ground through the ball. You know these trailers, they flicker once underway.

I've seen some hokey grounds on the individual lights, though, like self-tapping screws going through paint. Even the "Main ground" near the tongue can be shoddy.

 

[The motor guy]

Originally Posted By: eljefino
I bet you blew the fuse when you plugged the trailer in. Probably has a pinched wire that sometimes shorts to ground. The parking light fuse also runs your dash lights and you'd know they were out.

The parking light feed (brown?) runs down both sides of the trailer, so it probably splits near the connector. Run down the frame looking for trouble. Or bang around the neighborhood to see if it blows another fuse.

I'll check it out. I had just towed a trailer a couple weeks before, although I didn't check to see if the lights worked on that trailer. I switched to all LED lights on my trailers and haven't had problems since. I'm curious if I could just leave the regular lights on this trailer since it doesn't go in the water. I doubt it.

 

[The motor guy]

Are you guys saying the one ground on the trailer may not be enough?

 

[Rand]

usually those lights are grounded to the trailer not to any wires.

The ground then meets up with the ground wire from the wiring harness where ever they screwed it to the frame.

It could be any number of issues.
Usually the ground issue shows up after 1-5 years out in the weather not when new.