Electrical problem

[asherdav]

I have a 2018 gougar 25res 5th wheel and I noticed on our last trip that both rear marker lights had 1 tiny led that was lit on both sides. The whole light was not lit just 1 tiny light. I'm not sure how to go about fixing this. No lights on when the truck is disconnected. I can understand if all of the lights were lit but why just the two rear side lights. Any help would be appreciated

[chuckster57]

I have seen portions of LED lights go bad, unfortunately I’m not aware of any way to test individual LEDs. If it’s a sealed unit then I would just verify 12VDC at the light. You can take the light off, and then just plug into the truck, or you can jumper at the 7 way trailer plug.

Hold the plug with the locking tab at 12 o:clock facing you. A jumper between 11:00 and 1:00 will light up the marker lights.

[flybouy]

Originally Posted by asherdav

I have a 2018 gougar 25res 5th wheel and I noticed on our last trip that both rear marker lights had 1 tiny led that was lit on both sides. The whole light was not lit just 1 tiny light. I'm not sure how to go about fixing this. No lights on when the truck is disconnected. I can understand if all of the lights were lit but why just the two rear side lights. Any help would be appreciated

That sounds like some sort of cross feed from some 12v dc source. There is only one wire from the truck that feeds all of the clearencr lights including the running light circuit in the brake light fixtures. Are you certian the other clearence lights weren't dimly lit but perhaps the sun washed them out? I would connect the truck at night with the truck lights off and take a look around.

[asherdav]

As soon as it gets dark I'm going to hook up and plug in to see what's lit and what's not. You know sometimes I get a trailer wiring fault but I never put the two things together so perhaps it could be related?

[flybouy]

Originally Posted by asherdav

As soon as it gets dark I'm going to hook up and plug in to see what's lit and what's not. You know sometimes I get a trailer wiring fault but I never put the two things together so perhaps it could be related?

Could be. I'd start with checking the 7 way camper umbilical ground. Loosing the ground connection can result in some irregular lighting on trailers.

[asherdav]

OK tried the lights last night and 1 tiny led in the left and right rear side markers only. Truck connected with key off. So I'm thinking that it's not coming from the truck it's a problem with the trailer lights and it must be between the two side markers wiring or both lights are bad. Now when I turn the truck lights on both side markers light up as usual. Can it still be the lights or wiring?

[flybouy]

From your first and last post it appears that this only happens when the trailer is plugged into the truck. Logically it's associated with the truck. I would suggest checking the truck wiring. Do you have a multimeter and familiar with using it?

[chuckster57]

Have you tried a jumper on the trailer umbilical cord?

[asherdav]

Just got done checking with volt meter and it's coming from the truck on the brake circuit. Since the dealer wired it up I'll take a closer look at their work.

[asherdav]

Thanks for everyone's help. It's nice to find people willing to help us not so intellectually gifted.

[flybouy]

Experience doesn't necessarily equate with a "gift of intellect". It's the lessons learned that gives the impression of intelligence.

[Miloski]

This may sound strange, but check your wiring like suggested but check your brake controller. Mine went bad had the same issue on my 2019 RES25.

[asherdav]

Thanks to all that replied and just to let everyone know that it is fixed and the problem was the in bed wiring with the factory connections that the dealer installed.

[asherdav]

Yep you were right,truck wiring from the dealer install of the in bed trailer plug.