Trailer brake problems?

Discussion in 'Mechanic and Repair' started by lasher66, Aug 29, 2005.

  1. lasher66

    lasher66 LawnSite Senior Member
    Posts: 395

    Hi,
    A few months ago I bought a prodigy trailer brake controller for my 2003 Chevy 2500HD. I didnt have one before that, I just didnt use my trailer brakes (16X8 dual axle trailer). Well after I bought it and put it in it seemed to work fine. I plug in my trailer harness to my truck and the controller reads that it is connected. But when I start driving, I get all kinds of different errors of "overloads, or short circuits, or not connected when I hit the brakes" . Then once in a blue moon it will work for a few seconds.
    I traced all the wiring, cleaned all the metal on the trailer were grounds were mounted, put new wire nuts on all junction points. made sure there were no bare wires. Im not sure how trailer brakes work since they work off electronics but I think the only problem is in the brakes itself now. Can someone offer any more advice on what I can do. Thanks for your time.

    Lasher
     
  2. ed2hess

    ed2hess LawnSite Fanatic
    Posts: 13,078

    Did you check to be sure you had no bare wires inside the drums? Use ohm meter to check to see if there is any shorts to ground.
     
  3. fixer67

    fixer67 LawnSite Silver Member
    Posts: 2,104

    Electric trailer brakes work by using electromagnetic brake shoes. The more you push the brake pedal down the more power the controller sends to the shoe and the more they grip. Any thing any one asks me a trailer electrical problem the first thing I always asks is are they trying to ground though the trailer hitch ball? I would have to say that 75% of all the trailer electrical problems I have seen is because people thinking that the hitch ball was a good enough ground path and it is not. You could have a bad controller. And do like was said because if the shoes ware down enough on some types the wires for the electromagnetic start shorting out with the rotor or drum. One most types when you buy new shoes you get new electromagnets because they are all made as one.
     
  4. lasher66

    lasher66 LawnSite Senior Member
    Posts: 395

    its grounded to the frame of the trailer, not the hitch ball. I took the drums off and everything seems to look good. Do you think the electromagnets could be bad? The controller is new so I hope it isnt bad.

    Lasher
     
  5. fixer67

    fixer67 LawnSite Silver Member
    Posts: 2,104

    Well a quick way to test them is to get a car battery and hook it straight to the trailer brakes and this will lock the wheels solid as a rock and you can drag the trailer and the wheel will never turn until you cut the power. To do this just unplug the cable from the truck and sit the battery in the trailer or fixed to the tail gate and run the the ground to the trailer ground and then hot the brake lead. Then get in the truck and try to pull the trailer the wheels should slid and not turn until you cut the battery lose. This will tell you if the trailer brakes are working but will tell nothing about the truck or controller.
     
  6. ed2hess

    ed2hess LawnSite Fanatic
    Posts: 13,078

    I just jack up the wheels when I do this check and it works great. Someone else suggested using battery charger, I guess that would work? If the coil isn't working a resistance check can be done on them if you can get them out of the loop. I also run grouind wire and don't use frame.
     
  7. lasher66

    lasher66 LawnSite Senior Member
    Posts: 395

    I will give that test a try, but the problem I am having is that they are working on and off. Sometimes they will start working, then most the time my brake controller will give me an overload single or open circuit single.

    Lasher
     
  8. fixer67

    fixer67 LawnSite Silver Member
    Posts: 2,104

    Then you have bad wiring some where. Remove the wheel and look really good at the shoes and all the wiring. follow the wiring all the way to the truck. then if need be all the way back to the controller. you have a break and or short some where.
     
  9. evan price

    evan price LawnSite Member
    Posts: 28

    You said, "Its grounded to the frame of the trailer not the ball".. well what we mean is, do you have a dedicated ground wire that goes in the wire harness between the trailer and the truck? Some people don't bother with the extra wire because it might work just grounding to the frame of the trailer & grounds thru ball, but if you have a wire that connects ground on trailer to ground on truck it's how you should do it.
     

Share This Page