For some odd reason, all of a sudden my trailer brakes quite on me. I can have the truck in drive at a stop, try the trailer brakes with the over-ride button, and nothing. The last time I had the trailer hooked up, they worked fine. Any suggestions? I am going on a 3000 mile trip starting tomorrow afternoon!!! I was thinking it may be the ground, but all the lights work fine, it's just the brakes. I would really appreciate some things to check. Thanks!

John

 

Start by checking the ground connections and maybe resetting the brake controller.

 

Any time it comes to something electrical you always want to check the fuse or circuit breaker to see if it's blown or tripped. Is your brake controller on a fuse? Go there first. Then look at the wire harness in the truck, next the one on the trailer. You should look for broken wires at each connection. If all those are good use an ohm meter next to check the circuit. You should look for voltage at the truck connection without the trailer plugged in. Do you have a wiring diagram for your truck to see which wire to check? If it checks good it will be in the trailer. Wring out the harness if you can get to both ends. If not you'll have to go from the connector to where the wire ends at the trailer's brakes. Where ever you don't get voltage look at what supplies power to it, that's where the trouble will be. Good luck.

 

I just restored my trailers breaks about 2 weeks ago. They had been working fine, then intermitantly and finally just quit altogether. I pulled the right side drum off and found one of the magnet wires pulled loose, shredded and wrapped around the spindle. On the other side, the magnet wires had worn through the insulation where the little metal clips hold the wires to the magnet arm. A made the necessary repairs to the wires, removed all the metal clip and replaced them with plastice zip ties, reinstalled the drum and adjusted the shoes. All is good now.

 

How do you reset the brake controller?

 

The first place to look is the plug. Is it corroded? You need to keep those contacts coated with a thin film of di-electric grease. If not, have someone hold the controller on while you check the voltage on the brake plug. If you have voltage, you know you are good to there. It then is probably a broken wire on the trailer as mentioned by Mechanos - - happens quite often, regretfully.

 

Unhooking the brake controller form power, maybe a little wait time (minute or so), then plugging it back in should reset it.
I'd be looking for ground issues first, then checking the voltage coming out of the socket on the truck, then voltage right at the brakes.

Some trucks do not have the ground wiried into the trailer wiring, it just uses the hitch for the ground, and this is bad to do as your ground will change as you drive, depending on the contact of the hitch, and grease on the hitch or ball, etc. You can check this by seeing if the trailer lights work with the hitch disconnected, but having the wring harness plugged in.

Chris

 

jbevly wrote;I had the same thing happen to the GN last month, suddenly the GN was pushing the truck when minutes earlier they were working. Brake controller appeared to do nothing although the LED's implied everything was still hooked up. When we removed the hubs, (Dexter axles) we discovered during the winter while it sat unused, the bottom (return) springs rusted to the point they broke the next time it was used, but our GN is more than 10 years old. So if there's continuity on the brake signal wire at the axles, remove the braking hubs and inspect everything closely.
Nathan

 

Use your multi-meter and be sure you have power to the brake

 

Do you have dogs?

A ranch I worked for in college had a dog that loved to chew wires up. ( I woulda shot that dog if it was mine. Its like having a cow that wont milk.)

anywho. If my trailers brakes werent working, the first thing I did was crawl under, and check my wiring. Usually there was a wire chewed in half.


I use a simple continuity tester(test light). Thats all I have ever needed to correct any brake problem. After you check for chewed wires, check for power at the plug. Then follow your wires back to the hub, and check there.

this should help narrow it down.