4-6
Easy Fix
LiftMaster · Garage Door Openers
Safety reversing sensors misaligned, blocked, or disconnected.
Quick Answer
Error code 4-6 on your LiftMaster Garage Door Openers means: Safety reversing sensors misaligned, blocked, or disconnected.. This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
How to Fix It
1
Clean both safety sensor lenses.
2
Align sensors until indicator LEDs are solid.
3
Inspect low-voltage sensor wires for cuts/loose terminals.
4
Remove objects from door threshold path.
5
Test door close cycle.
Pro Tip
This is a common issue that most users can resolve without specialized tools. Try the first step before moving on to more complex solutions.
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