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 →

Frequently asked questions

What does the 4-6 code mean on a LiftMaster garage door opener?

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.)

What causes the 4-6 code on a LiftMaster garage door opener?

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.

Is it safe to keep using a LiftMaster garage door opener with a 4-6 error?

Yes, with caution. This is rated a moderate-severity fault.

How do I fix 4-6 on a LiftMaster garage door opener?

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

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.