Pontoon Boat & Deck Boat Forum

Hey everyone, I've been checking in here since the great divide, just have failed to register since then. Now that boating seasons wound down, time to make some fixes.

My first question or problem is it seems that my trailer is blowing the fuse in my truck for the running lights....only. Brake lights and signals seem to work fine, just after a while of the running lights being on 10-15 minutes.....pooof out goes the fuse.

How can I check to find out if it's something with the trailer or my vehicle?
It's a new trailer, plugs look good, plugs (truck & trailer) just slightly weathered but not carroded.

thanks, in advance for any help.

Look for a shorted wire in running lights wire, so trace the wires

Of it only happens when towing boat then that pretty sure eliminates truck. Sounds like a bare wire touching another but not constant. Does yours run through frame? I finally had to rewire mine and I couldn't find problem. I ran wire outside trailer frame and used the slip on wire protector and zip tied it to frame.

Check the ground wire to the trailer. If the ground wire is not a good connection, the trailer will ground through the ball on the hitch and as you drive, the connection will vary and sooner or later (mostly sooner) you end up with a high resistance connection causing high current flow and a blown fuse.

Yep, check the ground (usually white) wire first. Then if that's not it, check for abrasions in the running light wires (usually brown).

Yes, mine are ran through the trailer tubing, I'll try cleaning up the connectors first as I'd rather not pull all that wire out. The connectors are kind of brownish but not corroded, I'll try cleaning them up, any suggestions on that? What if I connect the lights to the truck without the trailer hitched to the truck, if it's the connector will it blow the fuse sooner or not at all?

Some where there is a short... ie a bare wire touching something.
Finding it will be the fun part.
Following the wire all the way along its trip is the way to find it.

Just get some new wires and tie them to the old ones good and pull in the new wire with the old one and be done with it, you need some help and don't rush it and you will be done in a half an hour.

Like Herb said, wiring harness's for trailers are actually pretty cheap. It's not worth the time, just replace it. JMHO