Guess I get to find out how good the dealer service department is...

Noticed that my Utility trailer running lights weren't coming on the other day while towing a load. Figured it was an issue with my trailer's wiring (but it's only a year old). Then I borrowed my dad's utility trailer a couple of days ago and saw that his running lights weren't working either.

Crawled under the 4Runner and verified no damage to the 4-pin connector, then used a test light to verify no power coming from the pin for running lights.

Plugged in a 7-pin to 4-pin adapter in the larger receptacle and still no lights.

So, I'll be taking it to the dealer this week for repair.

I know the service manager from high school, so I anticipate no issues.

Weird issue.

Brake lights and turn signals all work fine. Just can't tow a trailer after dark until it's fixed.

 

Yesterday, my dad and I figured since the stop and turn signals worked, that it was unlikely that there was a separate fuse for the running lights.

But, I just went out and double-checked and sure enough; 30amp fuse blown. Next step is to figure out why the fuse is blowing. Been towing the same couple of trailers for a year or more and no issues with prior vehicles.

 

Yeah, I'm not impressed with the location of the trailer plug-in. First time I hooked up the trailer, I thought that there was no plug-in for a minute. I have to get down on my knees to reach up underneath to plug in. I've also noticed water in the receptacle when plugging in when it's raining. Will start using the larger 7-pin receptacle with an adapter since it's easier to plug in one handed and is further away from the water getting splashed up by the tires.

 

Pretty common for trailer wiring to rub a wire bare causing it to ground itself out on the frame resulting in a blow fuse on the tow vehicle. Trace the wiring down on the trailer and you’ll most likely find the root cause.

 

I hope it's that simple. Trailer is a year old and is a very nicely engineered trailer with LED lighting...