Need Help.... Trailer fuse blowing when towing at night

[MVR 155]

Ive got an 06 H2, had it for about 3 weeks now. We took a trip down to the Ozarks with the jet skis for the holiday weekend and left very early am. About a block from my house I lost the running lights on the trailer (brakes/signals still worked), pullled the fuse and noticed it was blown. Got back late Monday so yesterday I spent all day messing with the trailer, pulled all of the lights off and checked the wires to make sure none were rubbed bare and shorting, put a new fuse in and all seemed fine in the driveway, I jumped up and down on the trailer and kicked it to see if it went out, jiggled the wires on the tongue etc.... (anything to re-create the issue). Drove down the block...fuse out again. Drove across town to my fathers house, took the trailer for a ride with his truck and no issues, then I hooked up his 8x13 Haulmark enclosed trailer and drove around with that... no problems, then I hooked up my friends Jet ski trailer.... no problems. The only issue is when I tow "my" trailer with "my" truck the fuse blows. Im at wits end with this, spent all damn day monkeying around with this and Im stumped.

One last thing..... I even swapped the 7 to 4 pin adapter as well with a different one.

ANY SUGGESTIONS PLEAAAAAAAAAAAAAAASE

[mikejr]

what fuse is blowing, one on the trailer or one on the H2?

When you say running lights on the trailer, you are talking the yellow clearance lights correct?

When the fuse blows, its just the running lights on the trailer that go out, nothing is bothered on the H2?

When the fuse blows, the brake and signal lights on the trailer still work?

[MVR 155]

Originally Posted by mikejr

what fuse is blowing, one on the trailer or one on the H2?

When you say running lights on the trailer, you are talking the yellow clearance lights correct?

When the fuse blows, its just the running lights on the trailer that go out, nothing is bothered on the H2?

When the fuse blows, the brake and signal lights on the trailer still work?

Sorry I should have been a bit more clear, its a simple trailer with no fuse box/panel, just the fuse in the Hummer is blowing (15 amp trailer running/park lamp fuse). Brake/Signal lights still function perfectly, the lighting on the hummer is not effected at all. Its a stand alone fuse for this particular function only.

Thanks

[audiofetish]

Originally Posted by MVR 155

Sorry I should have been a bit more clear, its a simple trailer with no fuse box/panel, just the fuse in the Hummer is blowing (15 amp trailer running/park lamp fuse). Brake/Signal lights still function perfectly, the lighting on the hummer is not effected at all. Its a stand alone fuse for this particular function only.

Thanks

Make sure that the trailer doesn't have anything grounding out with the running lights and that the actual ground for the wiring has good contact. I had the same problem with mine. It worked fine on my dad's H3 but it kept blowing the fuse on my H2. I checked all the lights and found one that had a wire touching the metal. Then I took off the ground on the harness and scraped off the paint where it connected to the frame and put it back. It works like a champ now. Good luck!

[tower]

You might want to check the actual plug as well (not just the adapter) for an intermittant short.

[MVR 155]

Originally Posted by audiofetish

Make sure that the trailer doesn't have anything grounding out with the running lights and that the actual ground for the wiring has good contact. I had the same problem with mine. It worked fine on my dad's H3 but it kept blowing the fuse on my H2. I checked all the lights and found one that had a wire touching the metal. Then I took off the ground on the harness and scraped off the paint where it connected to the frame and put it back. It works like a champ now. Good luck!

I have wiggled/pushed/pulled all of the wires in the trailer with no luck, ground appears to be good and well connected but I will definately pull it and make sure the contact is clean.

Thanks

[MVR 155]

Originally Posted by tower

You might want to check the actual plug as well (not just the adapter) for an intermittant short.

Dont think its the plug on the trailer otherwise it would have shorted/blown the fuse in the other truck and I dont think its the plug on the truck otherwise the other trailers wouldnt have worked.

[Dug]

mvr, I would be sure its in your trailer lights . Backing the trailer into the water is a great way to make corrosion . Make sure that even your small side lights dont have water in them making a short. Clean the white corrosion off of the bulb sockets even if it doesnt look like that is making a ground. Up the fuse 5 amps in your H2 . Replace the rear tailight bulbs even if they are working. Good luck , doug

[Dug]

Have you installed a electric brake controller by chance?

[HUMTECH]

FIGURE Trailer Lighting Provisions(c)



Looking at the schematic I would say it has to be in the trailer, check that circuit for the park lamps and make sure your park lamps on the trailer are not drawing more than 10a if they are 8a or higher I would try A 15a fuse. If ya can try installing A circuit breaker where the fuse goes with an amp gauge connected to it(not sure where to buy A tool like this I built my own) and then you can monitor the circuit to see if it spikes.

[mikejr]

have you checked to see what amp fuse is in the other vehicle that doesnt blow when the trailer is attached. Perhaps the draw is more than you think and its just popping the fuse. I agree, try fusing up a little after checking all the lamps for corrosion.

[MVR 155]

Ok to address the suggestions, first off the LED lights on my trailer are brand new, I pulled them apart when I messed with it on tuesday and there is no water in them at all (totally sealed). I actually also tried over fusing by 5 amps as well and it blew, the other truck has the same size fuse on its own circuit just like the Hummer does.

I am thinking that the new LED's may have some kind of intermitent short or something, I think Im gonna pick up a new set today and swap them in, if it doesnt solve the problem I think Im just gonna pull new wire through the whole trailer and be done with it.

I really appreciate the suggestions thus far and Im open to any other suggestions as well

Thanks everybody