Lippert Slide-Out: “3 red flashes”
warning RV slide-out error codes
What it means
Low battery at start of cycle. When you pressed the switch, the supply voltage was already below about 8 volts, so the controller would not start the motors.
Most likely causes
- Discharged house battery most likely
- Battery disconnect switch off or charger/converter not working common
- Voltage drop from corroded or loose connections common
Safe checks you can do yourself
- Connect to shore power or generator and try again.
- Measure battery voltage; below ~12V indicates it needs charging.
- Verify the battery disconnect switch is on.
- Confirm the converter/charger is powering the 12V system.
How to reset / clear 3 red flashes
- Restore proper voltage (charge battery or connect shore power).
- Energize the extend/retract switch once to reset the controller.
- Energize the switch again for normal operation.
When to call a technician
If the battery is fully charged and connections are clean but the code persists, suspect a controller or charging-system fault.
Applies to
Schwintek In-Wall slide-out controller (Rev B and later) · Lippert OneControl-managed Schwintek slide systems
FAQ
What does Lippert Slide-Out code "3 red flashes" mean?
Low battery at start of cycle. When you pressed the switch, the supply voltage was already below about 8 volts, so the controller would not start the motors.
How do I reset Lippert Slide-Out 3 red flashes?
Restore proper voltage (charge battery or connect shore power). Energize the extend/retract switch once to reset the controller. Energize the switch again for normal operation.
What is the most common cause of 3 red flashes on a Lippert Slide-Out?
The most likely cause is discharged house battery.
Related · Lippert slide-out
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Sources
- Schwintek In-Wall Slideout System Operation and Service Manual — Error codes section, code 3: Low battery, voltage below 8 volts at start of cycle (Lippert Components, Inc.)
- Schwintek In-Wall Slideout Troubleshooting and Component Replacement — Red LED 3 Blinks: Low Battery (RV Upgrade Store (Lippert document))
Note: The 8V start threshold is from the manual; the system can still run rooms down to as little as 8V but performance suffers at low voltage.
● Last verified 2026-06-29 · compiled from manufacturer documentation. Codes can vary by model year — always cross-check your unit’s manual.