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crazyro's avatar
crazyro
Explorer
Feb 09, 2021

No brakes on trailer

Hey guys and gals. Picked up a new to us travel trailer and can't get brakes to work at all. Had to be extra careful towing it. Plugged in, truck shows "Trailer not connected. Check brake wiring." message. Squeezing the brake controller to send full charge does nothing. (factory brake controller) Cleaned 7 pin connector with electrical contact cleaner, fine grade sandpaper. Lights all work. Checked any wiring I could. Didn't see any wires connected to frame so I'm assuming ground is done via ball? Battery is brand new. When I pull the breakaway switch, there's no whine, no sound, nothing from brakes. I'm not in a place where I can take wheels off, but the only other thing I can think of is that maybe magnets are shot or seized and/or causing a short? Trailer sat for about a year and a half. I may just have to take it to a shop and let them check it out. Anything I could check? Camper is a 2002 Cedar Creek (35 RLS).

TIA.
Seeking Advice

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  • BobsYourUncle's avatar
    BobsYourUncle
    Nomad
    Feb 09, 2021
    I would probe the wire (usually blue I think), with the controller held all the way on, each side of the connector.
    If you have battery voltage one side but not the other, it's the connector.
    If nothing each side, it is the feed. Check the fuse. Possible broken wire along the way somewhere.
    If voltage both sides, follow the wire and check at connection intervals. Or crawl under and probe at the wheels.

    Try putting a ground jumper between the truck and trailer to a good solid metal contact area.

    Somewhere in there the 12V is not getting through. By following it with a probe, you will see where the broken connection is.

    Check for evidence of rodents. They like to chew wiring.
  • agesilaus's avatar
    agesilaus
    Explorer III
    Feb 09, 2021
    You can buy a plug tester from Amazon, you plug it in the socket and cycle thru all the lights and brakes etc.

    Socket Testers

    I went thru this and it turned out the wiring was wrong.
  • crazyro's avatar
    crazyro
    Explorer
    Feb 09, 2021
    time2roll wrote:
    If you had a short the controller would say "short" or "overload" or some such. You have an open circuit which is a broken wire, cut wire, bad connection etc. Since none work, the issue is probably somewhere between the 7 pin connector and the first split to the wheels. Need a test light to poke at the wire. The ground is also connected through the 7 pin connector but if the lights work you must have a ground working.

    May want to start by checking the truck connector has voltage.



    So if I use a voltmeter on pins 1 and 2 (truck plug) and squeeze brake controller in truck, I should get full 12V, right?
  • time2roll's avatar
    time2roll
    Nomad
    Feb 09, 2021
    If you had a short the controller would say "short" or "overload" or some such. You have an open circuit which is a broken wire, cut wire, bad connection etc. Since none work, the issue is probably somewhere between the 7 pin connector and the first split to the wheels. Need a test light to poke at the wire. The ground is also connected through the 7 pin connector but if the lights work you must have a ground working.

    May want to start by checking the truck connector has voltage.

  • crazyro's avatar
    crazyro
    Explorer
    Feb 09, 2021
    LadyRVer wrote:
    When I had that "trailer not connected" error message, I was told to look inside the trailer plug and make sure those contacts were pinched together (the one for the brake wire.) Used a pair of needle nose pliers and brought them together more. I also cleaned and greased with die-electric grease before doing that. Worked after that. Might be worth a try.


    I shall try. I did check as much as I could, did pinch them to make sure they made good contact. Haven't tried die-electric grease. Did try plugging and unplugging several times.

    This this has me stumped. :/

    I appreciate the thoughts.
  • MarkTwain's avatar
    MarkTwain
    Explorer
    Feb 09, 2021
    LadyRVer wrote:
    When I had that "trailer not connected" error message, I was told to look inside the trailer plug and make sure those contacts were pinched together (the one for the brake wire.) Used a pair of needle nose pliers and brought them together more. I also cleaned and greased with die-electric grease before doing that. Worked after that. Might be worth a try.


    Agree 100%. Plug and unplug the electrical brake connector a few times. Die-electric grease is good maintenance.
  • LadyRVer's avatar
    LadyRVer
    Explorer II
    Feb 09, 2021
    When I had that "trailer not connected" error message, I was told to look inside the trailer plug and make sure those contacts were pinched together (the one for the brake wire.) Used a pair of needle nose pliers and brought them together more. I also cleaned and greased with die-electric grease before doing that. Worked after that. Might be worth a try.
  • crazyro's avatar
    crazyro
    Explorer
    Feb 09, 2021
    TenOC wrote:
    In my TT the brake wire was "cut" when the springs bottomed out after hitting a bump. Check the wire than comes out of a hole in the axels.


    Yes, checked all those and everything looks fine...
  • TenOC's avatar
    TenOC
    Nomad
    Feb 09, 2021
    In my TT the brake wire was "cut" when the springs bottomed out after hitting a bump. Check the wire than comes out of a hole in the axels.

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