Forum Discussion

Indycheez's avatar
Indycheez
Explorer
Oct 04, 2020

Connecting truck to TCamper

Hello, just joined the forum because I am a new owner of a 1982 Sun lite eagle TC. I am going thru it trying to familiarize myself with the workings of it. My question is on topic as to plugging the TC to the truck. I have a trailer harness plug at the rear of my truck and I have a round 4 pin plug on the front driver side of the TC. I was going to run an extension from truck hitch to the front plug of the TC. While inspecting the round 4 pin plug, it only had 3 wires running from it into the camper, with one pin not connected. Green White and Black. I have only the lights running along the roof of the camper. No turn signal or brake lights. I guess my question really is what does that plug operate? Is that for the running/cargo lights and for connecting 12v from truck to power the trailer 12v? Thank You.
B.
Truck Campers
  • Grit_dog's avatar
    Grit_dog
    Navigator
    Oct 05, 2020
    Technically the "standard" would be brown for running lights, but it's a 3 wire connection, so not exactly rocket surgery and on an almost 40 year old camper, having working lights is about 99% of the battle, who cares what color the wire is?
  • JRscooby's avatar
    JRscooby
    Explorer II
    Oct 05, 2020
    mkirsch wrote:
    The plug most likely DOES NOT conform to any "standard." Very much like my Palomino.

    My 2000 Palomino uses a standard 7-pin RV plug, but the wiring is COMPLETELY different. This was a complete surprise when I went to pick it up, and I ended up hauling it 150 miles home with one working turn signal, which was the only wire that matched up. It was a miracle that I did not get pulled over.

    I had to use my jumper pack and a couple of nails to probe the various pins to determine which pin made which light(s) light. Once I established ground, it was fairly straightforward. Then I wired up an adapter cable to run from the 5th wheel plug in my bed to the camper. They also make "power probes" now for just such a purpose.

    BTW, my camper has NO provision for an onboard battery, and never did.


    I'm hard of understanding. Why not change the wires to match standard instead of adding another connection to open a door for murphy?
  • mkirsch's avatar
    mkirsch
    Nomad II
    Oct 05, 2020
    The plug most likely DOES NOT conform to any "standard." Very much like my Palomino.

    My 2000 Palomino uses a standard 7-pin RV plug, but the wiring is COMPLETELY different. This was a complete surprise when I went to pick it up, and I ended up hauling it 150 miles home with one working turn signal, which was the only wire that matched up. It was a miracle that I did not get pulled over.

    I had to use my jumper pack and a couple of nails to probe the various pins to determine which pin made which light(s) light. Once I established ground, it was fairly straightforward. Then I wired up an adapter cable to run from the 5th wheel plug in my bed to the camper. They also make "power probes" now for just such a purpose.

    BTW, my camper has NO provision for an onboard battery, and never did.
  • Grit_dog's avatar
    Grit_dog
    Navigator
    Oct 04, 2020
    ^What he said basically.
    Green running lights
    Black 12V+
    White ground.
    Verify this though as old stuff = janky wiring sometimes.
    Just make an extension, 4 round one end 4 or 7 or whatever is on your truck on the other end.

    As said, if you want better charging of the house battery while driving, run dedicated larger gauge Wires from truck to house battery, fused.
  • KD4UPL's avatar
    KD4UPL
    Explorer
    Oct 04, 2020
    The 3 wires should be 12v +, 12v -, and running lights. I would just make up a cord with a 4 pin on one end for the camper and a 7 pin on the other end for the truck.
    However, if you really want your truck to do a good job of charging your TC battery you will likely need to rewire the TC with larger wires and keep everything as short as possible. A nicer way would be to put a short "pigtail" on the camper with a 7 pin plug and then install a 7 pin in the front of the truck bed like would be done for a FW or GN trailer.
  • ppine's avatar
    ppine
    Explorer II
    Oct 04, 2020
    Brown wire is missing. Thanks to Old Biscuit for the diagram.
  • Lwiddis's avatar
    Lwiddis
    Explorer II
    Oct 04, 2020
    Your camper’s interior lights and appliances should not be connected to the truck’s battery. They need a separate deep cycle battery that is charged somewhat when driving. Your TC’s clearance, tail and stop lights should be powered by your truck.

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