Trailer running lights, fuse blowing

[MissScarlet]

I have a 2016 Shorlandr Trailer for my SX190. My tow vehicle is a 2009 Honda Pilot Touring with factory towing wiring.

I've been troubleshooting my trailer lights for some time and have done a lot of research on this forum and others, with no avail. Here's what's happening:

I've tested my wiring on the tow vehicle with a plug-in type tester with the small LEDs and everything seems to work fine. When I plug in my lights, the turn signals and brake lights work perfectly and always have.

The trouble is the running lights. When I turn them on they work for anywhere between a few seconds to a few minutes, then blow a 20A fuse located in a small fuse panel in the back of the truck. I replace the fuse, and it happens again. Interestingly, the fuse does not impact the turn signals or brake lights because those always work, even when the fuse in the truck is blown. Only the running lights stop working.

I've replaced the harness, replaced the rear lights with LED's (some people said there might be too much power draw), and have inspected the wiring. I understand that this might be a grounding issue, but for the life of me, I can't find a white wire on a grounding screw ANYWHERE on this trailer.

Is there something I'm missing? Please help.

Again, I always have turn signals and brake lights (thankfully!), but can never go out at night because I don't have running lights.

Thanks in advance!!

 

[Babin Farms]

Your wire for the running lights is rubbed through somewhere and grounding out on the trailer. Check all of the spots that the wires run out of the trailer frame for chaffing.

 

[MissScarlet]

Your wire for the running lights is rubbed through somewhere and grounding out on the trailer. Check all of the spots that the wires run out of the trailer frame for chaffing.

Thanks! I will check it out and let you know.

 

[Redneck_4Play]

I had the same thing happen to me on my 2014 Shorelandr trailer. Had a heck of a time finding it but it ended up being a wire by the right side marker. Hope yours is easier to find than mine was.

 

[anmut]

Yep, you've got a wire missing insulation somewhere.

 

[MissScarlet]

So, update!

All wiring was inspected and I also did continuity tests on all wires. EVERYTHING looks great. I replaced my fuse and hooked up the lights (but did not have the trailer connected to the truck). All lights worked perfectly for an extended period of time. I was pleased!

However, when I connected the trailer tongue to the truck ball receiver, the lights dimmed slightly then blew after a few seconds. This is exactly what has been happening.

So, it appears that this is a grounding issue between truck and trailer rather than the trailer itself.

Can anyone tell me how to fix this issue? It’s been haunting me since I got the boat last year!

thabks

 

[MissScarlet]

I tested it with a wire and when i hold a wire to the truck receiver and another to the trailer to infuse it sparks!

 

[MissScarlet]

Update #2. Neighbor came over and we tested everything with his truck. So, it’s my truck. Everything looks ok from underneath. But i have no idea how to fix so I’ll probably take it in.