Check the fuse panel for blown fuses. Identify the circuit which controls the slide-outs, using the owner's manual, and verify that the fuse hasn't blown. Replace a blown fuse, and try the slide-out again.
Check the RV's battery voltage. The 12V DC motors which operate the slide-out mechanisms pull large amounts of power. If the battery is weak, the slide-out mechanism will not have enough power to operate properly. If the battery is weak, start the mobile home's engine, and then try to retract the slide-out again.
Remove the switch plate, and the switch from the wall which operates the slide-out. Check the circuit with a multimeter, also known as a volt-ohm meter. Press the leads against the positive and negative leads of the switch, and then activate the switch. The multimeter should read the presence of 12V DC current in the circuit. If power does not flow through the circuit, one of two problems exist. Either a wire in the circuit has shorted out, or a fuse has blown.
Examine the framework under and around the slide-out. Also examine the area inside the mobile home. If something as small as a table knife or spatula landed in the slider's area of operation, it can prevent the slide-out compartment from operating properly. Slide-outs are designed to not operate if anything presents a reasonable amount of resistance. This safety feature prevents human injury. Remove any body panels necessary to get an unobstructed view of the mechanisms.
Visually inspect the aluminum tracks under the slide-out. Two or three tracks (depending on the size of the slide-out) run the length of the slide-out, and are attached to the main frame of the mobile home via nylon rollers, or rack-and-pinion supports. Look for gravel or dirt built up in the track. Look for damaged rollers or bent support arms which cannot operate properly. These parts can be visually inspected from the exterior of the mobile home, underneath the slide-out.
