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subdev's avatar
subdev
Explorer
Sep 10, 2016

Brake Controller wires on F53

I have a '08 Hurricane 34B with a factory 4-pin tow package. I am upgrading to a 7-blade plug and am installing a Prodigy controller. Found the harness plug under the dash for the controller after a lot of searching! Underneath the chassis, just rear of the driver's seat, are two exposed wires strapped to a larger harness. One white and one blue. Both are terminated with butt connectors. I presume that the blue wire is the brake control wire, but I'm not sure if the white wire is ground or 12V power? Why would there need to be a ground wire there...what is it grounding, since my new 7-blade plug has it's own ground wire at the back bumper. If this white wire is a ground, does that mean I have to run a separate power wire from the back plug all the way back up to the battery? Thanks for any help.
Class A

7 Replies

  • usersmanual's avatar
    usersmanual
    Explorer
    Sep 19, 2016
    subdev wrote:
    Thanks usersmanual. I did manage to locate the correct blue wire in a rear bundled harness. I now have power and connectivity between the controller and the tow dolly. I haven't been able to take the rig out yet, but I still wonder if I need separate 12V power to the 7-pin plug? The plug came with a short black power wire and I'm trying to figure out where to connect it. The new 7-pin plugged into the old 4-pine, so like I said, everything looks powered up, but I'm fearful that the electric brakes won't actually work. And I doubt that the battery on the dolly will re-charge without the power.
    What am I missing? Thanks.

    not sure.What do u mean by
    The new 7-pin plugged into the old 4-pine,


    to have everything work u have to have 7 pole female to 7 pole male
  • subdev's avatar
    subdev
    Explorer
    Sep 19, 2016
    Thanks usersmanual. I did manage to locate the correct blue wire in a rear bundled harness. I now have power and connectivity between the controller and the tow dolly. I haven't been able to take the rig out yet, but I still wonder if I need separate 12V power to the 7-pin plug? The plug came with a short black power wire and I'm trying to figure out where to connect it. The new 7-pin plugged into the old 4-pine, so like I said, everything looks powered up, but I'm fearful that the electric brakes won't actually work. And I doubt that the battery on the dolly will re-charge without the power.
    What am I missing? Thanks.
  • usersmanual's avatar
    usersmanual
    Explorer
    Sep 10, 2016
    subdev wrote:
    Well, I can tell you that Fiur Winds built my 35' class A with only. 4-pin. I just bought a tow dolly with elec brakes and a 7-blade plug, which is why I'm upgrading to the 7 -blade and the brake controller. So do I only need to run power if I want the dolly battery to re-charge? Will the blue wire alone, power the brakes? Still don't know why another white ground wire is needed if the plug has ground at the back of the MH.
    Thanks.


    maybe try reading my post to you. Controller needs a ground also

    hundreds of Class A MH come with no plug or a 4 plug not all that uncommon
  • subdev's avatar
    subdev
    Explorer
    Sep 10, 2016
    Well, I can tell you that Fiur Winds built my 35' class A with only. 4-pin. I just bought a tow dolly with elec brakes and a 7-blade plug, which is why I'm upgrading to the 7 -blade and the brake controller. So do I only need to run power if I want the dolly battery to re-charge? Will the blue wire alone, power the brakes? Still don't know why another white ground wire is needed if the plug has ground at the back of the MH.
    Thanks.
  • sch911's avatar
    sch911
    Explorer
    Sep 10, 2016
    Wait what?

    I have never seen a MH without a 7 pin trailer plug installed at the factory....
  • usersmanual's avatar
    usersmanual
    Explorer
    Sep 10, 2016
    MountainAir05 wrote:
    This is the standard, but does not mean they follow it. Running straight to the battery with out a fuse would be bad. I would use the build in wire set under the dash. If you are only going to use to tow a vehicle you really don't need the 7 blade unless you are going to charge the tow battery also.

    https://www.etrailer.com/faq-wiring.aspx


    SO Hows he going to use a brake controller with a 4 prong plug???
    that's what the OP is posting about
    A controller needs Ground,brake lite+ power feed,12V power supply
    and a Blue wire from the controller back to the brakes
    The 7 pole is because some want a charge wire and back up lites working on trailer besides the controller blue wire, tail and signals
    and ground

    SEVEN in total
  • MountainAir05's avatar
    MountainAir05
    Explorer II
    Sep 10, 2016
    This is the standard, but does not mean they follow it. Running straight to the battery with out a fuse would be bad. I would use the build in wire set under the dash. If you are only going to use to tow a vehicle you really don't need the 7 blade unless you are going to charge the tow battery also.

    https://www.etrailer.com/faq-wiring.aspx

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