LiftMaster · Garage Door Opener Moderate

4-6 — LiftMaster 4-6 — Safety-Sensor Condition on Close Command

4-6 means a safety-sensor condition (the same as code 1-1 or 1-2 — sensors obstructed, misaligned, or wires shorted/reversed) was present when the opener was commanded to close. Check the safety sensors and their wiring. (Diagnostic meaning corrected against the official Chamberlain Group / LiftMaster Security+ 2.0 chart; flash-code meanings can vary by opener family — confirm for your exact model.)

Keep using it?
Yes, with caution
DIY difficulty
Easy
Typical cost
$25-40
Verified against
liftmaster.com ↗

The fix

LiftMaster Safety Sensor Kit (041-0136, replaces 41A5034)

Safety sensor fault present at the moment of a close command

$25-40 easy difficulty 30 min Tools: screwdriver

Diagnose first: Same root cause family as 1-1/1-2 — check sensor alignment and wiring before replacing parts.

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How to fix it

  1. Clear any obstruction and clean/realign the safety sensors until the LEDs are steady.
  2. Check the sensor wiring for shorts or reversed connections.

Why it happens

Typical signs: Door will not close · Flash code 4-6

  • Safety-sensor condition present at close command A 1-1/1-2 condition (sensors obstructed, misaligned, or wires shorted/reversed) existed when close was commanded.

Other parts sometimes needed

If diagnosis points to a failed part, these are the common replacements. As an Amazon Associate we earn from qualifying purchases.

  • Garage door opener safety sensors Common replacement
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More LiftMaster garage door opener codes

1-1 1-1 — Safety Sensor Obstructed, Misaligned, or Disconnected 1-2 1-2 — Safety sensor wire shorted or reversed 1-3 1-3 — Door control or wire issue 1-4 1-4 — Safety sensors misaligned 1-5 1-5 — No RPM Detected at Start of Movement 1-6 1-6 — Unexpected RPM After Stop at Open

All LiftMaster codes → All garage door opener codes →

Always unplug an appliance before servicing it. This guide is for informational purposes and is not a substitute for a qualified technician. Verified against manufacturer documentation: liftmaster.com.