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Trailer running lights via 4 pin connector

distram1500

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Good morning!
I did a quick search and nothing relevant came up for me, but I apologize if I missed answer.

My 2019 truck doesn't seem to provide power to running lights on the trailer. Turn signals, brake signals - all perfect. Connected same trailer to another truck - once again everything works.
I do not believe that there is a dedicated "running lights" fuse, or is there?

P.S. Tried all combination of light switch to no avail.

P.P.S. Just located "Parking Lights" fuse and will check it right away. That is probably the cause.

Thanks!
 
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NWRogue

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Check pages 314 and 315 in your owners manual. Specifically states the 4 pin only provides:
pin 1: Ground
pin 2: Park
pin 3: Left Stop/Turn
pin 4: Right Stop/Turn

running lamps is pin 7 on the 7 pin. No clue if Park = running lamps.
 

Richard320

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The underhood fuse box has a dedicated fuse for Trailer Tow Park Lamp. It is fuse F12.

It's one of those big ones. Blue. And if you didn't know, you have spares in that fuse box, around the edge in various spots.
 

distram1500

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The underhood fuse box has a dedicated fuse for Trailer Tow Park Lamp. It is fuse F12.

It's one of those big ones. Blue. And if you didn't know, you have spares in that fuse box, around the edge in various spots.
Yep! F29 on mine, and it is 20 amps. Going to pull it out now and check. Thanks!
 

Spiral534

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I am also connecting trailer to Ram with a 4 pin connector and running lights on trailer were not working. I triple checked the ground connections and signals/brake lights were working as they should.

It's actually on pages 225-226 of my manual. Weird but regardless, my Trailer Tow Park Lamp is F12 and there was a 20 amp big blue one already in place. I didn't have any spares but for testing, I swapped the fuse with F08 (Trailer Tow Backup) and now my running lights work properly on the trailer.

2 questions, is the Trailer Tow Backup used on the 7 pin harness exclusively? Could I have blown the original F12 fuse when I first connected the wire harness? This was before I realized that the wiring that came with the trailer did not work.

And do I need to worry about the bad fuse now in F08 if I am not using a 7 pin connector.

Thank you!
 

2019REBEL

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Hmmm I have a 2019 also and my running lights work when I plug it into the 4 pin connector.
 

Richard320

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I am also connecting trailer to Ram with a 4 pin connector and running lights on trailer were not working. I triple checked the ground connections and signals/brake lights were working as they should.

It's actually on pages 225-226 of my manual. Weird but regardless, my Trailer Tow Park Lamp is F12 and there was a 20 amp big blue one already in place. I didn't have any spares but for testing, I swapped the fuse with F08 (Trailer Tow Backup) and now my running lights work properly on the trailer.

2 questions, is the Trailer Tow Backup used on the 7 pin harness exclusively? Could I have blown the original F12 fuse when I first connected the wire harness? This was before I realized that the wiring that came with the trailer did not work.

And do I need to worry about the bad fuse now in F08 if I am not using a 7 pin connector.

Thank you!
Yes, yes, no. And you DO have a spare big blue 20A fuse. If you look for the one closest to the fuse puller tool, it'll be there against the edge.
 

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