Trailer lights inop

[CoastyAV8R]

When I plug in my camp trailer to the 7 pin plug my brake controller shows the trailer is hooked up on the brake controller and the trailer brakes do work but the lights on my trailer don't come on when I turn on the headlights.

Thoughts?

 

[Yo Hoot]

Normally I would spray the contacts on both connectors with electrical contact cleaner and plug in and out multiple times to scratch the connections so you get contact.

 

[BigPapa]

I've also had to take a small flat blade and tweak the contacts a bit to make good contact.

Might check the ground for the lights on the trailer.

 

[CoastyAV8R]

I've looked at the contacts and connector and all seems well, I'll check the grounds in the trailer. The fact that the brake controller knows when the trailer is hooked up and the trailer brakes work has me looking at other causes such as a relay.

 

[Ozymandias]

Try a reset of the FC by disconnect the battery's.
If there are fault(s) in the trailer(s) wiring, the FCM recognize this and after some time shuts off the circuits to prevent any further harm.

 

[brucejohnson]

Just for clarification, the clearance lights, tail lights, brake lights and turn signals are not working on the trailer? The trailer brakes are functioning OK?
Check the individual pins on the truck plug for respective voltages. Sounds like either a blown fuse or a loose/bad connection. Is the trailer plug a molded item or attached to the wiring with clamp and terminal screws? If your truck plug is good, try jumping the truck and trailer ground pins, then jumping 12vdc from the truck plug to each of the light pins on the trailer plug and observe the lights.

 

[Jim W]

My 2008, did the same thing this year. All of the brake, flasher, and turn signal lights work plus brakes, but the running lights would not light up when the headlight lamp switch is turned on. My copilot (DW) checks to insure everything is working before we pull-out. I go through the process of turning on each light such as RH/LH turn signal, she gives me a thumb up if the light is working. A brake check is done every time we leave also, by actuating the manual slide on the brake controller.

This year I received a thumb down on the running lights. So, upon investigation this turned out to be the 7-pin receptacle that is in the rear bumper. I did fix the issue but once in a while the lights still work not work. On a rough road there is enough bounce to cause the lights to lose contact with the harness and bumper receptacle. I would see them turn off in the side mirrors and then turn back on. I would than pull into the nearest rest area and reinsert the trailer wiring harness to insure a tight fit. This winter I am going to fix the issue by cleaning the contacts and insuring a tighter fit. After 13 years of use the contacts have spread a little in the 7-pin receptacle, at least on my truck.

Sometimes it is the simplest things that can go wrong.

Just my $0.02

 

[crispyboy]

Jim W - If you have fixed it before and they are still acting up it may be worth springing for a new receptacle in the truck. You may have just worn the thing out.

 

[Jim W]

I know what the issue is it is just one receptacle in the 7-pin connector on the truck. This somehow was pushed up when I connected the trailer power cord to the truck. I need to ensure that the lighting receptacle is position correctly.

I am also going to use a 7-pin connector that I uses to use for my axillary back-up lights that Geno's Garage use to sell. They were the White Night back-up light kit that you needed to add in the extra 7-pin connector with wiring for the lights to work. This will provide a tighter fit since I haven't used this in a couple if years. The White Night light housing was damaged in backing-up once and I just removed everything.

 

[CoastyAV8R]

I'm replacing my bumper this weekend so I'll be able to take a good look at the connector. The trailer is only a few years old and is kept in our shop so the plug on it is like new, the truck on the other hand is an 18 year old truck so there's that. Thanks for all the input

 

[bcbender]

had a similar issue on the 2012 2500 last week, no lights on our enclosed trailer,... I pugged it into my 20.. everything fine, plugged back into the 12.. everything but one brake light now... did again everything fine.. I suspect its worn or bad plug on the truck side

 

[Jim W]

Geno's use to sell a 7-pin connector repair kit, but I haven't seen this in their latest catalog.