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MOLOSE
06-17-2018, 10:59 AM
Brand new here and this is my first post. Currently my RV is out of commission and I am hoping someone can help. I just bought a 2004 Outback 26RS went on one issue free camping trip but never got to the second. My electric brakes are stuck on. I have confirmed that the breakaway switch is plugged in and functional. This all started when on day we noticed smoke emanating from the underside of the camper. After inspection I noticed that there were a few wires burned presumably do to a poor connection at the brake drums (crimp fell off?). I re-wired from the bottom of the RV through the axle housing and connected to both brake plates. I wired one hot and one ground to each. Now when a battery is connected or when connected to my truck the brakes are always on.... I sure hope I am being stupid here and there is not something more nefarious going on. I always have one lead that goes to the brake plates with 12v regardless if the brakes are applied or not.

Anyone have thoughts or questions?

JRTJH
06-17-2018, 11:13 AM
It almost sounds like you wired your brakes to the 12VDC hot line in the trailer umbilical rather than to the brake lead from the brake controller. The breakaway switch is connected to the same brake wiring, but is not the source for routine braking. The breakaway switch is the ONLY "always hot" lead to the brakes and that power source is "interrupted" at the switch by the pull pin that is connected to the tow vehicle. You should only have "12 VDC power" if the pin is pulled from the breakaway switch or if you activate the tow vehicle brakes and the brake controller applies power through the umbilical on pin #2. Otherwise the brakes should be "unpowered". If you connected a new line from the brake wiring you installed to a 12VDC "always hot" source, it sounds like you've "hot wired" your brakes and eliminated the brake controller circuit in the truck and at the umbilical connector (pin #2).

You might want to check the wiring that you installed and routed. I think you'll probably find the problem is in how you connected it to the umbilical wiring at the front of the trailer. Hopefully it'll be something as simple as that. If you need a umbilical wiring diagram to be sure it's wired properly, this is the one that's commonly used on all 7-pin connectors. From the connector to the junction box, it will be like this diagram. Once it enters the junction box, well, that's where you really need to pay attention to how things are connected. it's very easy to put a wire in the wrong "bundle" and cause the kinds of problems you're facing.

Let us know how it is going and what you find.

MOLOSE
06-17-2018, 11:30 AM
JRT
When the wire smoked and melted I simply added on the the only two wire that extended beneath the corrugated underside of the camper. I could really tell what wire came from where because it was just a melted mess. You may be right. I am going to go out and recheck my work and I will return with photos.

Thanks

bobbecky
06-17-2018, 05:26 PM
This actually sounds like there is no controller connected. Without a brake controller to modulate the voltage or provide no voltage when the brakes are not applied, it may be that the full 12 volts are being sent to the brakes.

JRTJH
06-17-2018, 07:29 PM
This actually sounds like there is no controller connected. Without a brake controller to modulate the voltage or provide no voltage when the brakes are not applied, it may be that the full 12 volts are being sent to the brakes.

In the first post, the OP stated, "I wired one hot and one ground to each. Now when a battery is connected or when connected to my truck the brakes are always on...."

It sounds like he bypassed the tow vehicle wiring connection, the umbilical connection on the trailer and wired 12 VDC battery power to one lead and a good ground to the other lead on each brake magnet. If so, then any time the battery is turned on/connected or any time the umbilical is plugged into the truck (charge line on the truck connector) his brakes activate. That is, at least to me, a statement that he "hot wired the brakes to the battery".... I hope he comes back with the solution to his problem and that he hasn't burned up the brake magnets.