Brakes working off & on

[olcoon]

Coming back from Goshen & our extended trip afterwards, we were driving through Indiana & Illinois, the road was pretty rough. The integrated brake controller on the truck started dinging & said I'd lost connection with the brakes. I pulled over on the shoulder & it was still plugged in, I briefly looked under the coach, didn't see and anything. Drove to the next rest area (without trailer brakes), & crawled under there for a better look & still didn't see a problem. I decided to continue on without brakes & look for some place to get them fixed. As we were pulling out of the rest area, they started working, and worked the rest of the way home. But sometimes the controller would ding, & by the time I'd look at it they were working. The only thing I can figure out is there is a loose wire someplace & shorts out/loses connection when I hit a bump. Yesterday DW sat in the truck & I got under the coach & wiggled every wire I could find & nothing happened, this included the umbilical cord, & were it plugs into the truck. Also, while enroute home, I unplugged the umbilical cord from the plug in, in the bed of the truck & plugged it in to the one on the bumper & it still did it. I don't know much about the electric brakes, so at this point I guess I'll have to take it to someone, but I'm afraid they'll say there has to be a problem for them to find/fix it, & right now everything is working. Anybody have any ideas?

 

[DougS]

I have had that problem and it wound up being a dirty connection on the plug. You might try cleaning plug contacts, you can even buy a small wire plug brush for that purpose. I also carry Electronic Cleaner by CRC to spray the plug once in awhile. Also, a small screwdriver placed behind the plug contacts might tighten the contacts.

 

[jnbhobe]

Roy. Dougs idea on the plug is a good place to start. Also I have found the magnet wires chafe on the actuator arm on the backing plate and cause a short.

 

[cookie]

All good ideas so far. You will need to pull the hub to inspect the magnet wires.
You might also take a look in the 4" square electrical box located under the pin box. This is where your umbilical cord connects to the trailer wires.
Roy, when you find the problem let us know what it is you find.

Peace
Dave

 

[Rickhansen]

At the pinbox there is an electrical junction box. Two screws to remove cover. The pigtail to your truck is spliced to the coach wiring with wire nuts. Check for corrosion and loose wire nuts.

Edit: Everyone elses ideas to check are good suggestions but be careful working on the 7-pin plug on your truck is has several pins that have 12 vdc at about 50 amps at it, maybe even with the key off.

 

[dbbls59]

Hello Roy. Another place to check is the wire inside the axles. I have had to replace this on two of my trailers in the past. I secured it on the outside of the axle instead of going back through the inside. This wire can have the insulation worn off and short out intermediately.