Running Lights through 7-Pin Trailer Plug Not Working

[sbuko213]

For some reason I have not been able to dive into yet, whenever I plug a trailer into my 7 pin connector on my 2019 3500, the night time running lights do not seem to be working. I have tried taking the lights out of auto, and nothing.

Keep in mind the brake lights, blinkers, and trailer brakes are working just fine. I have 2 trailers I use regularly (at 24' enclosed and a 14' equipment trailer) and I have the same issue on both. Both trailers have been plugged into other trucks and have not had this issue.

Could the whole connection housing be bad? Or is there possibly a loose wire?

 

[Daw14]

Check for blown fuses.

 

[turkeybird56]

20 amp blue cartridge fuse runs trailer running lights. On my 2019 1500 I think I have bad ground on trailer. NE way I only plug in trailer connector when all lights off on truck and door closed and truck off or it will blow fuse everytime. This is a problem specific to my truck but I would still insure all lighting off before plugging in trailer 7 pin just my experience these Rams so friggin picky on electrical.

On 1500 dat fuse is in exterior TIPM fuse 20 amp mcase as in cartridge fuse F12.

Added; left side brake,turn signal on separate fuse. Same for right side. Also 12v power charging separate. May be also for reverse lights but I use a 6/7 pin connector cause my stock trailer has no reverse lights just breakaway box.

 

[Tulecreeper]

Have you actually taken a circuit tester and made sure you have power to the upper left (10:00) pin?

 

[2003F350]

Definitely check to make sure you're getting power to all pins in your connector. There's a chance it's a blown or missing fuse, could also be a bad wire.

 

[Jim BB]

Like all the above have mentioned check plug with test light or multimeter make sure you are getting 12v power use ground from truck first from bumper or frame then use ground from plug just to confirm plug ground ! if no power go to tipm and check circuit breakers and fuses for popped or blowen ! if they are good go back to 7 way plug if factory unplug harness from the 7 way check for power and if power take apart 7 way plug in bumper or replace ! But if still no power at connection time to start chasing for broken wire!

 

[2003F350]

On another note, I'll say this: It may still be the trailer. Here's why I say that:

On my flatbed, things were working right until I'd plugged in into my 'Wagon a few times, then I started having issues with the running lights/turn signals. However, I did NOT have an issue with our travel trailer, and the flatbed had no issues behind my wife's F150 she had at the time. Turns out the issue was the style of plug on the trailer.

If you look at the receptacle on the truck side, you'll see the 'prongs' are kinda wedge-shaped and have a spring-type quality to them. The plug on our travel trailer was similar to this, so the contacts would press into each other. HOWEVER, the flatbed had completely flat blades that didn't push back toward the prongs in the truck's receptacle. I swapped that for a style similar to what's on our travel trailer and everything started working fine.

So it COULD be the trailer side still - it's something to check.

 

[Jim BB]

On another note, I'll say this: It may still be the trailer. Here's why I say that:

On my flatbed, things were working right until I'd plugged in into my 'Wagon a few times, then I started having issues with the running lights/turn signals. However, I did NOT have an issue with our travel trailer, and the flatbed had no issues behind my wife's F150 she had at the time. Turns out the issue was the style of plug on the trailer.

If you look at the receptacle on the truck side, you'll see the 'prongs' are kinda wedge-shaped and have a spring-type quality to them. The plug on our travel trailer was similar to this, so the contacts would press into each other. HOWEVER, the flatbed had completely flat blades that didn't push back toward the prongs in the truck's receptacle. I swapped that for a style similar to what's on our travel trailer and everything started working fine.

So it COULD be the trailer side still - it's something to check.

2003F150
you are quite right!!! but he has tried his truck on 3 different trailers and all have the same issue ! brake, turn signals,and the electric trailer brakes work just fine on all 3 of other trailers just no running lights ( night time lights) What Are The Chances Its The Truck Plug ???? Very Slim!!!! But possible! Just saying

 

[2003F350]

2003F150
you are quite right!!! but he has tried his truck on 3 different trailers and all have the same issue ! brake, turn signals,and the electric trailer brakes work just fine on all 3 of other trailers just no running lights ( night time lights) What Are The Chances Its The Truck Plug ???? Very Slim!!!! But possible! Just saying

No, OP says he has 2 trailers that have the same issue, that have been plugged into other trucks that do NOT show the problem. It leads one to believe it is the truck, but I posted my story to advocate that it MAY be the trailer plug if it's a cheap plug, which MOST trailers use the cheap $5 plug instead of the much better $25 plug.

 

[sbuko213]

Hey guys thanks for all the replies. I dove into it and the F29 fuse was blown. Changed that Friday. Just checked this morning and we’re back in business