[soundman5000]

I have a 10-12 year old ( From Home Depot ) utility trailer and the lights will not work with my new 2022 3500 Limited.
The trailer uses the flat 4 pin connector and my new truck has the trailer package so I have all the connectors but I have no lights when my trailer is connected to my new truck.

I connect the trailer to my old 2002 Ford work van and lights work perfect.

I purchased one of those plug in led trailer light testers and when I plug it into my new truck those test led's show my truck light connector is doing as designed but when I connect my trailer I again have no lights.

The trailer has older in incandescent trailer lights and I thought about changing them out to new LED but can someone even suggest a place I could start to figure this out? I can't understand why my lights work with my van but not my new truck and the tester shows everything is working when I plug the tester into my new trucks connector and my vans for that matter...

Do I have a hidden on and off in the menu? I found the backup alarm on and off in the menu ?
Can anyone suggest what wrong?

 

[H3LZSN1P3R]

Check the ground wire on the trailer. The old van it may be grounding through the ball and working but the new truck still has paint in the hitch and it is not able to ground through the ball would be my guess because your tester proves its not the truck…

 

[Loki223]

Yup. What @H3LZSN1P3R said. Needs to ground through the connector not the ball.

 

[soundman5000]

Thanks folks! I was stuck not knowing what to do next...

 

[Loki223]

The current ground wire currently attatches to the frame. Just add another that is tied into the utility trailer wiring and goes to the 4 way connector

 

[H3LZSN1P3R]

The current ground wire currently attatches to the frame. Just add another that is tied into the utility trailer wiring and goes to the 4 way connector

Or just grind the paint off the receiver and the hitch 😂

In all seriousness though i would add a new ground that goes to all the lights like mentioned and swap the 4 pin for a 7 pin (last part is optional but i just hate 4 and 5 pin connectors lol)

 

[soundman5000]

Or just grind the paint off the receiver and the hitch 😂

In all seriousness though i would add a new ground that goes to all the lights like mentioned and swap the 4 pin for a 7 pin (last part is optional but i just hate 4 and 5 pin connectors lol)

I think I may just rewire my old trailer with newer LED lights. Kits are dirt cheap and I have a broken plastic lens anyway. Im not well versed in all things towing and never owned a RV and not even clear about the different ends ( plugs ) , All I know is my new RAM has a few plugs so I'll try and figure out some options this weekend.
The reason I purchased a 3500 is I intend to do some car hauling so I will be learning more about towing / trailers soon as Im shopping for a car trailer now. But, as of now l I have only used 4 pin connectors and no I don't like them either...