Lost Trailer Running Lights and Dash Lights

[MR V]

I picked up a new 14' utility trailer with several LED running lights on it. After driving about 30 minutes I lost my dash lights (instrument panel lights) along with the truck and trailer running lights. The trailer was plugged into the 4 flat plug. After I got home, I found the 15A fuse (labeled Park Lamp) in the engine compartment was blown. I replaced it and now have my dash and truck running lights back. I have not yet tried the trailer again, but I will when I have some time. It has been several years since I have towed a trailer in the dark, and when it was, it as a 2 place snowmobile trailer. The brake and turn signal lights worked fine. Just the running lights on the truck and trailer went out, along with my dash lights.

Doing a little investigation, it looks like the 4 flat plug runs off from different wires then the 7 round plug. Is the 4 flat plug running lights fused separately from the 7 round plug running lights? My thinking is to run the trailer on the 7 round plug with a adapter to a 4 flat. Maybe all the LED lights are drawing too much for the 4 flat plug. I thought LED lights would not draw that much.

My truck is a 2002 Ram 2500.

 

[AH64ID]

I would guess there is a problem with your new trailer.

 

[gsbrockman]

I couldn’t begin to guess how many LED lights it would take to pop a 15A fuse.

As already mentioned......check the trailer over well. Perhaps there’s a section of the wiring ran between a wooden board and a metal crossmember, and it is chaffed and grounding out.

Additionally.......you’re on to something with trying the 7 round to 4 flat adapter. If the problem goes away, that could condemn the 4 flat on the truck as being the culprit.

 

[TFucili]

Trailers have notoriously poor wiring. Almost sure to find a pinched, or damaged wire shorting out somewhere on the trailer.

 

[MR V]

Everyone, thank you for your input. I have reconnected the trailer and it has not blown a fuse. I wiggled all the wiring a couple of time in all the light areas and no problems.

I also inspected all the wiring and did not see any problem.

Back to my original question: Is the 4 flat plug running lights fused separately from the 7 round plug running lights?

 

[Timd32]

Back to my original question: Is the 4 flat plug running lights fused separately from the 7 round plug running lights?

From what I see in the drawings.

The "factory" 7 round is referred to on the drawings as the "aftermarket" tow connector.

Then there is a 10pin tow connector, that looks like a rectangle plug in the rear that could be used.

It does not show a 4 flat, looks like that was added. if they used the 10pin square with one of those pre made harnesses that plug into the truck harness its all the same from what I see.

Both of these connectors are fed from the same fuses.

They both also tie into the regular wiring for the turn, stop, running lights.

 

[HPSimpson]

Ram 4 pin and 7 pin are fed from same fuses on '19 Ram truck.

 

[TFucili]

Pull the fuse you just replaced and see if the 4 pin goes dead, to prove it out.