RV slide-out not working: troubleshooting by slide type

Common symptoms

• You press the switch and nothing happens: no motor sound, no lights on the controller.
• The room moves slowly, stops partway, or only moves in one direction.
• One side moves a few inches and stops.
• The room goes out or comes in crooked.
• Red and green lights blink on the slide controller or the wall touchpad.

Quick checks before anything else

• The house battery is charged, and the engine or generator is running or the RV is plugged in.
• Lights and other 12V loads you don’t need are turned off.
• Transit bars (the metal bars that lock the room for travel) are removed.
• Nothing blocks the room inside (furniture, rugs, open cabinets) or outside (posts, trees, a folded-over seal).
• Leaves, water and branches are off the top of the room.
• The RV is level, and on a motorhome the parking brake is set.
• The slide fuse or breaker on the 12V panel is good.

What causes it?

• Low battery voltage The most common cause. The room crawls, stalls, or the controller shows a low-voltage code.
• Blown fuse or tripped breaker Nothing happens at all, and the controller lights stay dark.
• Bad ground or loose connection The room works some days and not others.
• Something in the way The room stops at the same spot every time, or a motor current fault appears.
• Motors out of step On in-wall slides, the room comes out crooked after it was stopped partway.
• Failed motor, wiring or actuator One side won’t move, or the motor runs and the room doesn’t.

Step-by-step: RV slide-out troubleshooting, low voltage first

When your RV slide-out is not working, start with power, because low voltage can look like a dead motor or a bad controller. Do these steps in order, then read the section for your slide type.

1. Find out which slide system you have Check the owner’s manual packet and the controller label. In-wall (Schwintek) and SlimRack slides have a motor in each side wall. Through-frame slides have tubes and a motor or actuator under the RV. Hydraulic slides have a 12V pump with a fluid tank.
2. Measure the battery voltage Put a meter on the posts. A charged 12V lead-acid battery reads about 12.6 volts at rest. Lippert says to charge if an in-wall controller sees less than 11 volts. A SlimRack controller flags low voltage below 12 volts and will not move the room at 10.5 volts or less. Keystone notes that being plugged in may not be enough, so charge a weak battery first. If it won’t hold a charge, see our guide to an RV battery not charging when plugged in.

   

3. Help the battery while the room moves Lippert says to have the engine or generator running, or the RV on shore power, before you move a SlimRack room. Keystone also says to turn off lights and other 12V items you don’t need. Never jump or charge the battery from the controller’s power posts. Lippert says to do it at the battery.
4. Check the fuse or breaker Find the slide fuse or breaker on the 12V panel. Lippert says an in-wall slide needs at least a 30-amp breaker, and the RV maker’s papers show where it is. If a new fuse blows right away, there is a wiring fault, and that is a job for a tech.
5. Clean and tighten the power and ground Check the battery terminals, the ground wire to the frame and the plugs at the controller. Lippert’s through-frame and above-floor manuals say over 90% of unit electrical problems come from bad ground connections. With the battery disconnected, clean off corrosion and tighten anything loose.

   

6. Clear the path and meet the safety locks Remove transit bars and anything in the room’s path. Some systems also have interlocks (safety checks that block movement). Lippert’s in-wall manual says a motorhome’s ignition must be off. SlimRack wants the parking brake set and the transmission in park or neutral. Other Lippert systems need the ignition on, so check your manual.
7. Read the fault lights Find the controller and press the switch. On Lippert in-wall and SlimRack systems, the green light blinks to show which motor and the red light blinks the fault code. Write the code down before you clear it, then look it up in our Lippert slide-out error codes. If no lights come on in one or both directions, Lippert says to unplug and replug the switch wires at the board. If that fails, the switch or its wiring is bad.
8. Re-time an in-wall room that runs crooked Lippert says the controller loses its zero point (its starting count) when the room is not run fully in or out. Hold OUT until the room is fully out, bring it in 8 to 10 inches, and repeat at least three times until both sides move together. From then on, hold the switch 3 to 5 seconds at each end.

Differences by slide type

After the checks above, the fix depends on the drive system.

Lippert in-wall (Schwintek)

Each side has its own motor. If only one side moves 2 to 4 inches and stops, Lippert says to press the switch while a helper pushes the stuck side. Lippert calls code 8 the most common code. It usually means pinched or broken wiring, or a bad or unplugged motor. Code 5 means too much motor current, often from an obstruction, debris in the gear rack, or a wiper seal caught on the floor.

To bring the room in with an error showing, use the electrical override: press the mode button on the controller six times fast, hold the seventh press about five seconds until the lights flash, then hold IN. Override does not keep the motors in step, so stop if one side lags. Re-time the room afterward.

Lippert SlimRack

With the touchpad controller, minor faults clear when you press IN or OUT, and major faults clear with the SET STOPS/CLEAR FAULTS button on the back of the touchpad. After a major fault, Lippert says a dealer must reprogram the controller. The rocker-switch (auto-programmable) controllers go into Emergency Jog on a major fault, so you may need to press the switch many times. If the power is out or the override fails, Lippert’s last resort is to remove both motors and push the room in evenly. Both sides must move together. See the SlimRack fault codes for each flash pattern.

Through-frame electric

Lippert’s chart says a motor that runs while the room doesn’t move can mean the actuator has come loose from its front mounting bracket, so check the jam nuts. A slow room points to low voltage, a poor ground or very cold weather. If the room stalls mid-travel, crank it a short way with the manual override, then try the switch again. To crank it by hand, disconnect the battery first. Then use a 3/4 inch socket or a fifth wheel landing gear crank on the override extension. Turn clockwise to retract. Stop at the end of travel, because Lippert warns the gears can strip.

Hydraulic

A 12V pump pushes automatic transmission fluid (ATF) to the cylinders. Keystone says to keep the fluid within 1/2 inch of the top of the tank with the rooms in, and Lippert recommends ATF with Dexron III or Mercon 5. Keystone adds that the pump’s self-resetting breaker usually sits within 18 inches of the battery. When it trips, the slide seems to work only some of the time. To retract a Lippert through-frame hydraulic room by hand, run a drill with a hex bit clockwise in the override coupler. Lippert says a standard 38 inch room takes about 45 seconds.

When to call an RV tech

• A new fuse blows right away, or the breaker keeps tripping.
• Codes 6, 8 or 9 come back on an in-wall slide after you check the plugs.
• A SlimRack touchpad needed an override. Lippert requires a dealer to reprogram it.
• The room is stuck out and the override won’t bring it in, or only one side moves.
• You hear grinding, see a bent rack, or the room sags or drops.
• Hydraulic fluid leaks under the RV.

For how each system works and what each part does, see our RV slide-out repair guide.

Common questions