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[Wrench]

When I went to extend the front slide the last overnight stop of a multi-week trip the right slide motor of the long front slide did not activate. We spent the night with the slide in and drove home. After reading about the Schwintek mechanism I found the slide controller and noted the LED trouble code it was indicating which was that the right motor was inoperative. There was documentation on the Web about the connections from the controller to the slide motor. Checking the plug going to the right motor against this document, and against the other side motor, it was clear that something was wrong with the motor since the two motor power wires show an open circuit.

The motor is accessible from inside the coach by taking a piece of metal trim off. This piece of metal also appears to be a part of the structure that holds the slide movement assembly to the coach. It is held on by several of the ubiquitous self-drilling, self-tapping screws and three of those screws are on the motor side of the trim panel. One goes below the motor, no problem. The one up from there goes in about where the middle of the motor is. This one had broken off – the nub of the screw was still attached and the rest of the screw was stuck to the motor where the big magnet is. The top screw – see below.

At this point I could detach the motor wiring harness (about 6” long) from the coach connector. Some ohm meter work showed that the coach wiring was OK but the motor power circuit was still open.

To get the motor out for inspection the slide must go out a few inches to remove a screw that secures the motor from the outside. I put a reasonable amount of pressure on the slide (with the motors disconnected from the controller as advised by the documentation) and it would not budge. At this point I called the dealer and asked for a service appointment soonest. The best they would do was a month in the future even though I bought the coach there, it was only 4 months old, and it seemed for sure to be a warranty issue. I suppose I could have started up the chain of command at the dealer to make my case as to why this was unacceptable but I didn’t.

After applying between 150 and 200 pounds of force on the right side of the front slide I was rewarded by the whirring sound you hear when the slide extends. This noise is from the gear train that allows the small motor to move the large, heavy slide. After removing the access screw from the outside the motor was removed. With the dust cover removed the armature contacts (where the power goes to the rotating part of the motor) were revealed and the ohm meter showed a typical value for a small DC motor of this type. Careful examination of the wiring harness and how it attaches to the printed circuit board on top of the motor revealed that the nylon header that attaches the wires to the board was bent just a bit to one side just enough to break the metal of the header as it goes through the circuit board. The fix was to remove the header and solder the wires directly to the circuit board. Strain relief was provided by some liquid electrical tape where the wires enter the circuit board. The motor was reinstalled and the slide works just fine.

So what pushed the nylon header out of position and broke it? It is pretty apparent that the top screw of the trim panel, when it was installed, did the damage as it came through the mounting material and continued about ¾” into the motor’s space. Just a little bit to one side and all would have been fine, a little to the other side and it would have been a clean, immediate break and would have been found when the slide wouldn’t deploy. But the way it was a few thousand miles of road vibration and a few slide deployments shifted things and a break occurred.