RV Travel trailers and fifth wheels are equipped with a break-away switch design to apply full power to the trailer brakes should the trailer detach from the hitch and ‘break away’ from the tow vehicle.
On a travel trailer the break-away switch is mounted somewhere on the a-frame. On a fifth wheel it’s mounted near the pin-box.
The the placement of the switch means it is exposed to the elements… especially on a travel trailer… and should be inspected regularly to insure proper operation.
A good time to check the break-away switch is when you are de-winterizing or otherwise getting the trailer ready for the RVing season.
Pull the pin from the housing and inspect for dirt and/or moisture. Spray a little contact cleaner into the housing to clean the contacts. Check the cable attached to the pin for weak or abraded areas and replace if necessary.
To check for proper operation of the switch jack one of the trailer wheels off the ground and spin it. While it is spinning pull the pin from the switch. If the wheel stops firmly the switch is working.
When hitching up pay attention to where and how you connect the break-away switch cable the the tow vehicle.
The cable should NOT be connected to the hitch but rather to some secure part of the tow vehicle. Make sure there is enough slack in the cable to allow for turns and make sure it cannot be snagged.
Once I spotted a fifth wheel rig parked at a gas station. It was parked in the approach to the gas pumps and the RVer was checking under the hood.
I stopped to see if I could help and the RVer said that he had just started the turn into the pumps when the brakes on the fifth wheel locked up. He wasn’t sure what was wrong but had ERS on the way.
While I was talking with him I noticed the pin had been pulled out of the break-away switch. The cable had somehow gotten snagged and when the RVer made the sharp turn to line up for the pumps the pin pulled out.
The RVer was a little embarrassed but relieved that it wasn’t a serious problem.
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