Alpine 5th wheel: one brake locked up

[Thunk]

I've done some searching but haven't found a match for my symptoms yet:


2019 Keystone Alpine 5th wheel with about 6k miles on it. Was moving sites today and (luckily) just as we approached our exit the truck (Dodge Ram Cummins) threw an error to check the trailer brake wiring, followed by a warning that the trailer brakes were not operating. I had not touched the brake pedal for quite some time, and was not touching it when the error occurred. I squeezed the lever on the controller and felt the trailer tug me, so I knew at least some of the brakes were still working.


We exited and pulled into the campground, which was fortunately right off the interstate. When I walked around the trailer I found that the rear, passenger side brake on the 5th wheel was hot and smoking. The other three wheels appeared cool and normal. (I also confirmed that the emergency brake line hadn't been pulled. Although, I would have expected all wheels to have been dragging if it had).



I unplugged the brake line from the truck and re-plugged it. We checked in and moved to our space. That move was relatively short, but the wheel didn't seem to be dragging or heating back up. It's unclear to me if the brake has reset yet or not. I have not had a chance to pull the wheel yet (maybe tomorrow).



My questions is:


The Ram detected an error, but I'm not really sure how. I figure there's either a wiring problem that triggered the one brake or a mechanical issue that caused the brake to seize. The fact that the truck detected the condition seems like a clue as to what went wrong, but since I don't understand how the truck detected the error, I'm not sure what the clue is telling me.


As I understand it, on a 7-pin connector, 1 wire feeds all four brakes. So what is the the controller on the truck monitoring? Does anyone know, How did it detect that one wheel was (spontaneously) braking?


Thanks,


Thunk

[chuckster57]

It probably detected an error based on the number of amps the brake system was drawing. I would remove the hot wheel and drum after it cools down and look at the magnet wiring and the adjusting springs.

[GeoRandy]

My problem may be similar. Normal driving, don’t have to even have used the trailer brakes for an hour on the highway, start getting “check trailer wiring”, “trailer disconnected “, “trailer brakes disconnected “. Camping World checked unit, no problem detected. Based on a cleared trailer, went to RAM dealer. They found a trailer control module error code that indicated either the trailer wiring was bad or the module was failing, so I replaced the module ($480). Same thing is happening...help!
Works great for an hour, then goes intermittent. I can’t detect any pattern for its misbehavior. Acts like something warms up, then starts acting up.
2018 Keystone Avalanche 365MB & 2018 RAM 2500.

[NevadaRich]

Geo,

Sometimes the plug from your Trailer, after being connected to your truck, doesn't make a good connection, you may have to move it around, even after you have pushed it all the way in??

[JRTJH]

Originally Posted by GeoRandy

My problem may be similar. Normal driving, don’t have to even have used the trailer brakes for an hour on the highway, start getting “check trailer wiring”, “trailer disconnected “, “trailer brakes disconnected “. Camping World checked unit, no problem detected. Based on a cleared trailer, went to RAM dealer. They found a trailer control module error code that indicated either the trailer wiring was bad or the module was failing, so I replaced the module ($480). Same thing is happening...help!
Works great for an hour, then goes intermittent. I can’t detect any pattern for its misbehavior. Acts like something warms up, then starts acting up.
2018 Keystone Avalanche 365MB & 2018 RAM 2500.

The very FIRST thing I'd do is fill the 7 pin connector with a quality dielectric (electrical contact grease).... It sounds like you've got either some loose fitting connections or some arcing that's causing the computer monitor to sense a disconnect.

[GeoRandy]

That’s the thing...I’ve done all that, including using a wire tie to be sure the plug stays tight during travel.
Good feedback...keep it coming!

[vampress_me]

Don’t know if this applies or not. But on our 2016 F-350 I was getting error message about the trailer being disconnected or a brake issue. Whenever I’d get the messages, I would have no trailer brakes working. I would check by manually sliding the brake controller switch. The lights would keep working. It was happening with 2 trailers of ours, camper and horse trailer. Ford tried to say it was a trailer issue until I pointed out it was with 2 trailers, one of which was new. They could only pull an error code once and I don’t remember what it was. They ended up replacing the 7 way plug under the bumper of the truck (I think beau did they were tired of dealing with it). It was a simple unplug the plug from the wiring harness, and plug a new one in. That solved the problem. We still don’t know what was the issue, but for the rest of the time we owned the truck it worked properly.

[GeoRandy]

Thanx! I’ll plug into my bumper outlet tomorrow morning as we pull out. Hopefully, I’ll have the same results you did, and I will have the problem area isolated!