Replace the control switch and check for 12-volt power if the pump doesn't work when the button is pushed. Check for power at the switch. If there is no power you need to replace the key switch.
Check the retract valve if the pump runs but the slide doesn't move. The retract valve is located near the bottom along the slider mechanism. If it is broken it will appear broken in half or worn to the point that it does not seal. To replace you must unscrew the valve and screw in a new one.
Check if the solenoid valve opens if the pump runs but the room fails to open. If the valve does not open it may need to be cleaned or replaced.
Extend the retract valve to see if it is bad if the pump runs but the room will not retract. Also check the wiring; if the wire or valve is bad, the piece must be replaced.
Check the control box to see if it is functioning if the pump runs but the room fails to open. If it is not the control box, retract the solenoid valve to see if it is functioning properly. Make sure the T-handle is closed on the solenoid valve. If either the control box or solenoid valve has no power, it must be replaced.
Check the solenoid valve or manifold check valve if the room creeps out after being retracted. If these parts are not functioning properly or leaking they must be taken out and replaced.
Check if the RV is leaking oil or if the solenoid valve is bad if the room creeps in after being extended.
Adjust the room stops if the room doesn't seal tightly when fully extended or retracted. This is done by tightening the screws or bolts (depending how it is attached). Doing so will raise the stops and make the room seal tightly.
Check the rack sensing valve if one side of the room will not move while trying to extend or retract the room.