electric brake problem

[Dave in NY]

Do the electric brake magnets get weak? I recently got a used trailer and have rewired it front to back.New wires to each wheel also.Have the same brand of plug and wired exactly like another trailer I have that works fine.Every thing is well grounded.I can use a 6vt. gelcell battery and jumper wires on the brake and ground terminals of the plug and hear the magnets hum and the wheels will lock.The breakaway system will lock the wheels too.My truck,controller work fine on two other trailers.Im thinking the magnets have gone weak if there is such a thing?

 

[Mike Groom]

Dave, If your brakes lock up when you apply power to them it's not the brakes on the trailer,check your wiring to be sure your getting power from the controller to the correct wire on the trailer,if it is you have a bad controller,some are fused so you might want to check that also.

 

[Anonymous-0]

Isn't your truck 12 volt? Why test with 6 volts?

 

[Dave in NY]

Thing is I have since been hooked to 2 other trailers that the brakes work just fine.One is a friends Hudson car hauler and the other a homebuilt hauler I built about 8 yrs. ago. Maybe I do have something wired up wrong but kind of doubt it.I will check it out this weekend if it doesn't rain too much.

 

[Dave in NY]

Yes my truck is 12vt.Because thats what sat handy on my work bench.

 

[Jim H. SW-PA]

I had a camping trailer I bought off a fellow that had a bigger truck had same problem I cleaned magnets on both wheels still not working. Came to find out that he relied on the ball to ground the system. He told me later he always had trouble with the lights too. I just run a ground through the plug directly to brakes, and a secondary one to trailer frame for lights. no more problem.

 

[Welding man]

Magnets don't get weak, but they do wear out. The face of the magnet that contacts the inside of the drum can become worn into the wiring and short out or the magnet face and the drum can become grooved until the magnet cannot attach itself to the drum with enough force to pull the brake arm back and apply the shoes.Sometimes the brake arm seizes up on the pivot bushing and the magnets are working fine but the arm can't move to apply the brakes.I'd say the next move would be to pull wheel and see whats going on inside.

 

[old]

Sounds like its not your truck or the trailer but it sounds like the new trailer is wired different then your other 2 trailers and if thats the case yes you will have problems. I see that all the time because it seems no 2 people wire things the same way. If your truck works on your other trailers but notthat one and you know the brakes work on your 6 volt battery it only leaves one thing and thats how the wiring is
Hobby farm

 

[ScottyHOMeY]

You might double check your work inside the plug. One I put together worked fine for a few trips but eventually one or two strands of one wire or another got loose and crossed over to another terminal. Might be worth a look.

Just another vagrant thought. You didn't step on the brake and activate the controller while you were testing the breakaway did you?

 

[Dave in NY]

Had the drums off when I checked and repacked wheel bearings.Every thing looked fine and nothing seized up.Minor surface rust on drum surfaces,polished that off with emery cloth.I don't get a fault indication on the controller.The problem isn't a short,it's more like an open.I will figure it out.Going to take a better look at the socket on truck.All the road salt this past winter might have corroded something.Plug on the trailer is new.

 

[Dave in NY]

Trailer is grounded through the wiring to the truck.I know the problem you mention,I rewired a boat trailer to fix a that same thing.

 

[buickanddeere]

You just proved the magnets and brakes good. The problem is else where.
Odds are it"s the classic high resistance return path through chassis.
Run a separate - return from - the connection directly at the brakes up to the truck"s - battery .

 

[Dave in NY]

Just eliminated the trailer from the problem.Friend stopped by and we pluged it into his truck,had a wheel jacked up off the ground, he hit the control and it locked up the brakes.So-- problem is on my truck. The socket is about 4yrs. old,looks a bit crappy inside.Am going to wire in a new one,check all wires,fuses,breakers, ground etc. Funny thing though truck worked fine on two other trailers after I couldn't get it to on this trailer.Might be intermitent problem.I WILL figure this out!Lots of good advice from you guys! Will update later.

 

[massey333]

dave ,since you said your friends truck worked the brakes OK,do you have a Chevie and he had a Ford or Dodge?Chevrolet factory wired their truck backwards from ASAE standards for a number of years.The brake wire was one of the wires reversed from the others.Just something learned over the years and listening to dealers cussing.

 

[Dave in NY]

Both trucks are Chevy.His 2 yrs. old, mine 12 yrs old.Didn't know that about the different brands.Something to watch for if-when I switch.Have an old 3/4 ton PowerWagon,what a workhorse! Don't drive it much lately,THIRSTY!

 

[massey333]

Dave his truck will be the same as Ford and Dodge,GM changed sometime around 1999-2001 to the standard.If both your trucks are Fact.wired then they will be different.