Hopefully a quick question. I have a 2012 JKU with only 8,000 miles. I rented a U-haul trailer today but when I went to pick it up I had NO trailer lights. Trailer was just used the day before and was good. I went home and hooked up to the neibors trailer and NO trailer lights again.

I checked the wiring and it looked good. I checked the fuse which should have been M2. a 20Amp fuse. It was good.

Is there some kind of a trickI'm not aware of to get these things working?

Thanks

 

Assuming you are using the stock 4 pin or 7 pin wiring harness, I would start by removing the driver's side rear stop light as that's where the connection is made for the trailer wiring harness. It just daisy chains with the connectors for the rear light.

 

Put a volt meter on the harness pins. Start with the volt meter ground touched to the frame and the hot to each of the 3 pins for stop and L/R turn. If those are good, then put the ground of the volt meter to the ground connector (to rule out a bad ground wire). If everything is good at the harness, then the problem is likely on the trailer.
Obviously, a two person operation.

 

Thanks for the replies. I climbed under the jeep one more time and found the harness is not plugged into anything. It is just ziptied up. There is a grey connector which is pretty much plugged right back into itself. I would guess this is the connector that loops into the drivers side tail light that you mentioned. When I looked the first time I saw the harness headed back over the rear axle and did not notice it made and loop and came right back to the back again. I check things out tonight. Thanks