Last year I lost all DC power in my XLR (from a shorted wire but that's another story). Nothing DC would work regardless of what I did as the DC bus was shorting out. I couldn't get a dealer to send a repairman as I was in the boonies so I had to bring all 3 of my slides in manually.
Only one of my slides was a Schwintek and luckily, it was the smallest bedroom slide. I had to cut the silicone sealant and pull the rubber boot down from the outside on both sides of the slide to expose the set screw. Then I remove both set screws and used a slot screwdriver to gently raise the motor a half inch or so. AT THIS POINT, TRY TO PUT BOTH SET SCREWS BACK IN. You want to hold that motor in place. When done on both sides, the slide could be pushed in easily.
Once the slide was in, use something to wedge it in as it can freely come back out again. I was able to put a block of wood on top of the slide from the inside.
The rest of the story for us: The dealer fixed the short (factory defect), but when he extended the Schwintek, I had not put the set screw back in and the motor on one side slipped off and was destroyed. The dealer replaced that motor and we were back in business!
Cedar Creek Silverback
Mazda Miata TOAD for sex appeal