Do you have MCD shades? If so, they use a coin battery in the wall mounted controls. Pop the cover off and slide in/out for replacement. May be time to replace the batterys cause that would be my luck; one demo operation and they fail...lol
Welcome to the forum. Consider adding your rig specs to your signature line
2010 Tiffin Allegro Bus, 36QSP
Retired Federal Firefighter/Fire Officer
On the way...