Trailer brakes are 'locked'

So then I'm guessing the battery charge wire ended up making a connection with the brake wire? I think that would be the only path...

Kvmsp8 wrote:
Problem solved! The 7 pin cable to the truck had been pinched and a couple of wires had broken.

All fixed now...

Kevin

Kevin, that's great news. I've seen that wire get pinched when folks run the 7pin cable between the spring bars, and the trailer frame. The wire gets pinched on turns.

glad you found the problem.

Problem solved! The 7 pin cable to the truck had been pinched and a couple of wires had broken.

All fixed now...

Kevin

It doesn't really sound like a wiring short. If something was shorted, fuses would blow (but that can't happen because brakes lines aren't fused) or the rig would be in flames.

Thanks everyone for your suggestions! The breakaway switch seems to be OK and I suspect it's a short somewhere else in the wiring.

At this point, I'm going to call in a mobile RV tech but can't get him here until next week. I'll update this thread once we've found the issue.

The good news is that my batteries seem to have survived their 'ordeal'.

Kevin

allen8106 wrote:
Make sure the break away pin is inserted correctly. They can be inserted 90 degrees off and will not work.

I'd bet on this being the problem. Quickest way to confirm if it's the switch is to simply cut one of the wires to the breakaway switch. If brakes release then you either have a bad switch or the pin is not correctly inserted.

Water in the breakaway switch will not cause the brakes to apply. If it did then every TT in the country would be locked up by the side of the road every time it rains. :E

Also, pulling the breakaway pin while the TT umbilical is plugged into the TV will sometimes result in a fried brake controller further confounding the problem.

If checking the pull pin doesn't seem to fix the issue, unhook one of the wires going to the break away switch. Due to manufacturing tolerances, maybe you bought a bad switch???? Just a crazy possibility!!! Or maybe the pin itself is "bad" from when it was molded. If you have the old switch compare the two pull pins.

If you have a volt/ohm meter, check the switch for continuity once you unhook it. Or check for voltage on both sides of the switch if you don't want to unhook it.

Hope you get it fixed quick!!!

Make sure the break away pin is inserted correctly. They can be inserted 90 degrees off and will not work.

Another possibility is water in the break away switch is causing it to complete the circuit.

Try pushing in the plastic key pin again. IT takes alot of pressure to go between the spring loaded key capture. It will make a loud clunk when you get into the locked position. Then it take a rather hard pull to get back out again. All of this is necessary to keep from accidentally pulling the plastic key pin out.

Now that you know you are draining your good batteries leave the negative cable disconnected until you get all of this figured out... You don't want to further kill your brand new 6VDC batteries...

Well now we all know a little more of the mystery which is good hehe...

Roy Ken