Forum Discussion

Earl_E's avatar
Earl_E
Explorer
Jun 23, 2018

Electrical connection between trailer and truck problem

I did a really dumb, dumb thing. The plug between the truck and trailer was sort of corroded and not always making a good connection so I used what I had--WD-40 to clean them. It worked. BUT now the the male plug simply falls out of the female receptor when I plug it in. The truck connector cover has little tongues sticking out to hold the male plug but none of them line up. Any ideas about what I could now spray on both parts to eliminate the oil? I can't really get into either piece to clean anything. Any other ideas will also be greatly appreciated. You would think at 79 I'd know better but I still make supid mistakes! LOL
  • groundhogy's avatar
    groundhogy
    Explorer
    Jun 24, 2018
    Now, as to why you sprayed WD40 into the connector....
    Are you having some connection problems? Or just preventative maintainance?

    groundhog
  • Bobbo's avatar
    Bobbo
    Explorer II
    Jun 24, 2018
    Earl E wrote:
    wa8yxm wrote:
    4 6 or 7 pin round or flat.

    Round connectors have a bit of a "bump" on them that a notch on the dust cover locks down on. If the dust cover spring is not springy enough it wont' lock (or if you do not push it far enough on) a rubber band over the cover and plug body may help till you can make other fixes.
    . I'll check for gunk because the bump doesn't line up the hump!

    When fully inserted, the bump and hump will line up.
  • groundhogy's avatar
    groundhogy
    Explorer
    Jun 24, 2018
    Hi Earl,
    You did fine. WD40 isn't a bad thing.
    Yes the truck connector cover should have a tooth on it to hold on to the trailer connector to hold it in. If they dont line up, then you rotate until both connectors slip into each other. Then the truck connector cover tooth should grab the trailer connector.

    I hope I understood your post and I hope this helps.

    groundhog
  • Earl_E's avatar
    Earl_E
    Explorer
    Jun 24, 2018
    wa8yxm wrote:
    4 6 or 7 pin round or flat.

    Round connectors have a bit of a "bump" on them that a notch on the dust cover locks down on. If the dust cover spring is not springy enough it wont' lock (or if you do not push it far enough on) a rubber band over the cover and plug body may help till you can make other fixes.
    . I'll check for gunk because the bump doesn't line up the hump!
  • mike-s's avatar
    mike-s
    Explorer
    Jun 23, 2018
    Like wa8yxm asked - what type of connector? For the common 7 pin Bargman, the cover on the male (vehicle) end has a tab which should lock the trailer end in place when it's fully seated.

    Maybe the tab is broken, maybe the spring on the cover is broken, maybe there's gunk in either connector which is keeping them from fully mating.

    (the gender is defined by the contacts - 6 of the 7 are male on the vehicle side, so that's considered the male end, although it's less ambiguous and confusing just to refer to vehicle/trailer)
  • Dusty_R's avatar
    Dusty_R
    Explorer
    Jun 23, 2018
    often times each round pin/conductor in the plug has a slot in it. If so, take a small screwdriver or jack knife and push in each slot and spread it a little.
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Jun 23, 2018
    4 6 or 7 pin round or flat.

    Round connectors have a bit of a "bump" on them that a notch on the dust cover locks down on. If the dust cover spring is not springy enough it wont' lock (or if you do not push it far enough on) a rubber band over the cover and plug body may help till you can make other fixes.

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