Breakaway Switch Problem

[barmar]

Just found out after a test that the breakaway switch doesn't appear to be working--pulled switch and brakes didn't activate trailer was unhooked), Didn't have time to troubleshoot but would appreciate any hints/ideas as to what next. Is there a fuse for this system?Thanks, B

[Irlpguy]

It is very difficult to tell if the brakes have activated when the unit is parked when you activate the breakaway switch. On my 2012 there is no audible click or sound. Personally I would not be worried and would check it when hooked up to the TV. But if you really must, then check for voltage at the wheels, the wires are fairly accessible. Doing it the hard way would be to jack up a wheel and try to spin it. I would guess it is indeed working, you are just not hearing anything to indicate the brakes are on.

[H. John Kohl]

I found an easy way to check the electric brakes on our trailer was to wave a compass past the wheel at axle lever from front edge to back edge of the tire. If the compass needle points to the center of the axle and stays, moves, continuing to point there then the Magnet is active. Note it could be either end of the compass needle because the polarity of the wiring, which does not effect the braking function, will attract either the North or South pole of the compass needle.

If the break away switch is not working then I would immediately make sure the controller on the truck is working.
The break away switch receives 12 volts from the trailer battery and is wired in line with the controller 12 volts to the brakes. I would remove the cover on the (4"x4") box under the hitch and check the wiring.
No the emergency break away should not have a fuse on it.

Good luck and let us know what you find.

[Tom S.]

To add to what John said, if the compass doesn't indicate the magnets are working, it could also mean your battery is dead or dying.

[barmar]

Update! Thanks for the ideas. It finally stopped raining here so I got out to the trailer. Jacked one wheel as suggested and did some checks. One, I confirmed that the breakawsy Switch (BAS) does not work when the trailer is stand alone, not plugged in but, when I plug it in to the TV the BAS works the way it should but obviously of little use should the trailer ever break away--maybe about 1-2 sec of braking!! So. the BAS is getting power (12V) from the truck but nothing from the trailer batteries which I checked and they're good--13.6V . Checked as much of the wiring, grounds etc that i could see but it's tough determining which wire goes where, etc and I'm not an electrician. Not sure what to do now--may have to take it to an expert--$$$$.
Cheers, B

[Irlpguy]

I have been working on my daughters horse trailer this morning and one thing I was checking was the BAS. Her unit has an extra battery similar to a backup battery for a security system. This battery is wired in series with the main batteries so if one fails one would hope the other would have sufficient voltage to activate the brakes.

The horse trailer also has a plastic covered box that contains a terminal strip, the wires from the TV plug go to this box/terminal block and are then routed to the proper place in the trailer from there. In the case of the BAS that wire connects to the terminal strip where the brake wire comes from the TV, It then carries on to the trailer brakes.

Since my 5er is in for warranty I cannot go and check on it but I recall it has a metal box where the plug to the TV goes into. I would check inside that box, perhaps as with my daughters horse trailer there is a terminal strip with all the wires being routed from there.

The BAS only acts as a switch, when the pin is in place the contacts are broken, when that pin pulls out the circuit is completed. There must be 12V at the BAS when the TV is not connected or it would be worthless.

All the wiring from the TV plug and the BAS is at the pin block, it would have to be traced back into the trailer from there.

Knowing that my daughters brakes were being supplied power, I tested the compass theory, all I can report using two different compasses was that this method is very unscientific and inconclusive. Perhaps it was a problem with my compasses.

If you are in the lower mainland or VI barmar, then send me a pm and I will be glad to call you and try to help further.

[8.1al]

The compass has worked fine for me

[jimcol]

I've used a compass for years to test for power to the electric brakes. If power is getting to the brakes I have never had the compass method fail. Jim

Quote from Irlpguy

"Knowing that my daughters brakes were being supplied power, I tested the compass theory, all I can report using two different compasses was that this method is very unscientific and inconclusive. Perhaps it was a problem with my compasses."



[/quote]

[H. John Kohl]

quote:Originally posted by barmar

Update! Thanks for the ideas. It finally stopped raining here so I got out to the trailer. Jacked one wheel as suggested and did some checks. One, I confirmed that the breakawsy Switch (BAS) does not work when the trailer is stand alone, not plugged in but, when I plug it in to the TV the BAS works the way it should but obviously of little use should the trailer ever break away--maybe about 1-2 sec of braking!! So. the BAS is getting power (12V) from the truck but nothing from the trailer batteries which I checked and they're good--13.6V . Checked as much of the wiring, grounds etc that i could see but it's tough determining which wire goes where, etc and I'm not an electrician. Not sure what to do now--may have to take it to an expert--$$$$.

Cheers, B

I would look in the 4" square metal box under the pin. You should be able to trace the two wires from the break away box into that box. One wire will go to the breaks and the other goes to the battery.

OOPS rereading your post you say you have voltage when the truck is hooked up.

Look for a fuse in that box. If not then you have to chase the 12vdc wire that has voltage from your truck to your batteries and find where it is "OPEN". This also suggest 99% that your truck is not recharging your batteries when you are towing.

Good luck and let us know when you find.