4 Pin/ 7 Pin Trailer Hook Up Issues

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OC455

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So, I had a Opt7 tailgate light bar that I had laying around and decided to see if it would work on the kids 05 Ram.

Check out the 4 pin plug that is there, and it had some bad corrosion on it. Cleaned it and hooked it up. Only thing I got was the bottom red running light. No turn/hazard lights or brake lights.

Decided to back the 05 up to the camper. Plugged in the 7 pin to see if that was ok. Turned on the running light no problems. Still, no turn/hazard lights or brake lights working on the camper.

I am assuming I have a break in the wiring some where?
 

turkeybird56

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YUP, break in wire from plug to lights (probably). For chits and giggles, did U try hooking up to the 4 pin on one of yer newer trucks and see if works?

Of course, on the older trucks, you could also have fuses blown on the older trucks, but my $.27 is on broken wires going to the Opt 7. Hence the suggestion to plug into one of your newer trucks and see if works.

ALSO, U may want to research the model number of the Opt 7 and see if it is the one for the 05/06 you are trying to put on.

REF TRAILER LIGHTS: Could be a connector issue, your 7 pin adapter issue (old/worn out/wrong one, etc) and/or fuses in the fuse box as separate lights run on different fuses.
 
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OC455

OC455

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REF TRAILER LIGHTS: Could be a connector issue, your 7 pin adapter issue (old/worn out/wrong one, etc) and/or fuses in the fuse box as separate lights run on different fuses.
The 7 pin is factory already on the truck...
The 4 pin hangs behind the bumper. I plugged the light bar into the 4 pin on my 19 and everything worked on the light bar. No broken wires there.
 

turkeybird56

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The 7 pin is factory already on the truck...
The 4 pin hangs behind the bumper. I plugged the light bar into the 4 pin on my 19 and everything worked on the light bar. No broken wires there.
OK, then U know the problem is on the 05/06. There are separate fuses in the fuse box that run: Running lights // Turn Signals-Brake lights by side // Reverse lights // Aux charge port. U need to check all of them.

ALSO, look up the model number of the Opt 7 and see if it was made/will fit for the year truck.

ADDED: I know 7 pin on the truck, was referring to adapter you plug in. But if U going to the 4 pin, well, here's a thought. Does the 7 pin adapter on the truck work? If so, after checking all else to include fuses, you could buy a Curt Harness adapter which goes in line with the 7 pin and gives you another 4 pin, and that should work and plug into that 4 pin.
 
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OC455

OC455

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There are separate fuses in the fuse box that run: Running lights // Turn Signals-Brake lights by side // Reverse lights // Aux charge port. U need to check all of them.
Ok, so there's separate fuses that are for the trailer wiring for turns, brake and such. Will take a look.
 

turkeybird56

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Ok, so there's separate fuses that are for the trailer wiring for turns, brake and such. Will take a look.
YUP: 1 Cartridge fuse blue 20 amp for running lights. I do not remember the other ones as MY 19 always blows this fuse if when I initially plug in 7 pin, and truck not powered down, gotta be a bad ground somewhere on trailer just not investigated as I know there is that particular problem in my case.
 
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OC455

OC455

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Looking at the fuse block, looks like #33 it the Trailer Tow Connector (20amp), #46 is Trailer Tow Left Turn (15amp) and #47 is Trailer Tow Right Turn (15amp), check those first.
 
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OC455

OC455

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#46 & #47 fuses were both blown. Replaced and now everything is good with the world. I'm thinking when I plugged in the 4 pin without cleaning it first, it caused the short to happen and blow those two fuses. The OPT7 triple tailgate light bar is still one of my favorite add-ons to a truck. Just waiting on some clips to attach it....the 3M double sided tape I don't feel will adhere to the box because of the Rhino liner that is there. Should of read up and known about the separate fuses.
 
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