No Brakes

[fun2bethad]

Hey all,
I have a 1965 Caravel and the brakes aren't working at all. Here's what I know:

1. The breakaway switch had something dropped on it a year or so ago and had a hole in the top of it. I replaced it this fall but it didn't fix the problem. When I opened it up, it was rusted and definitely shot.

2. The brake controller in the tow vehicle indicates that the brake is being applied as the numbers go up when I apply the brake. It's pretty obvious the brake is not engaging though.

What is the best place for me to start? Any ideas? Thanks for any feedback you can offer!

[Inland RV Center, In]

Originally Posted by fun2bethad

Hey all,
I have a 1965 Caravel and the brakes aren't working at all. Here's what I know:

1. The breakaway switch had something dropped on it a year or so ago and had a hole in the top of it. I replaced it this fall but it didn't fix the problem. When I opened it up, it was rusted and definitely shot.

2. The brake controller in the tow vehicle indicates that the brake is being applied as the numbers go up when I apply the brake. It's pretty obvious the brake is not engaging though.

What is the best place for me to start? Any ideas? Thanks for any feedback you can offer!

You can trace the wiring with an "OHM" meter.

If the tow vehicle is sending a voltage to the brakes, then check the connector, as well as which pin goes to whatever circuit.

Andy

[bobnmary]

could be a simple as non-standard pattern on the trailer plug, which is pretty "standard" haha on something that old. i forget what putting on the brakes did to mine when i first got it, but it didn't involve slowing down. i think mine went to a dead short and blew the fuse on the controller, but it's been a while. i had to re-wire the whole plug. actually i had to buy a new plug because the old one was completely shot. throw the book away, buy a new plug, identify each circuit, and start over from there. as you identify the circuits you should come up with one that uses a lot of current and when you put +12v on it the wheels make a little noise (like brakes coming on).

[TG Twinkie]

If you want to identify the function of each of the wires in the umbilical cord. Use a battery charger, connect the black lead of the charger to a clean spot on the trailer frame then connect the red lead to each of the wires in the umbilical cord one at a time. You should also check the brake wiring at each wheel to make sure it has a good connection. The proper adjustment of the brakes is also a necessity.

[TG Twinkie]

I forgot to mention that the break away switch has nothing to do with the operation of the trailer brakes from the Tow vehicle. The break away switch is wired to the house battery. When functioning properly the break away switch will activate the brakes if there is a good battery and the pin has been pulled. The break away switch will should be wired into the brake circuit in parallel to the TV circuit.

[Jammer]

Originally Posted by fun2bethad

Hey all,
I have a 1965 Caravel and the brakes aren't working at all. Here's what I know:

1. The breakaway switch had something dropped on it a year or so ago and had a hole in the top of it. I replaced it this fall but it didn't fix the problem. When I opened it up, it was rusted and definitely shot.

2. The brake controller in the tow vehicle indicates that the brake is being applied as the numbers go up when I apply the brake. It's pretty obvious the brake is not engaging though.

What is the best place for me to start? Any ideas? Thanks for any feedback you can offer!

Electrical problems are notoriously difficult to diagnose over the Internet so I don't give step-by-step suggestions any more.

There are a few things you can try however.

First of all, you should pull the drums and inspect the brakes and bearings. That's periodic maintenance that should be performed regularly, and it may provide some answers. For example, the mechanism may be corroded to the point where it just has to be replaced.

Beyond that, using a test light while someone applies the brakes at the controller will help identify any wiring problems. The most common points of failure are at the tow vehicle connector and at the connection between the chassis wiring and brake magnet.