I had just the opposite happen with my power gear slides, the slide would extend but not retract. On my 2003 Bounder Diesel the relay boards were in the compartment with the inverter, mounted on the back wall of the compartment. The boards were right next to each other so I swapped the wiring plug between the relay boards along with the fuse and was able to retract the extended slide using the other slides controls. When I got home I replace the relay boards.
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