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error Chamberlain

Error Code 4 UP / 6 DOWN

The garage door opener will not close and the lightbulbs flash. Safety sensors are misaligned or were momentarily obstructed.

? What Causes This

Safety sensors are misaligned or were momentarily obstructed.

How to Fix It

  1. Realign both sensors to ensure both LEDs are steady and not flickering.
  2. Make sure nothing is hanging or mounted on the door that would interrupt the sensor's path while closing.

Source: page 38 of the official manual

From the manual

Manual page 38 — Chamberlain error 4 UP / 6 DOWN

This error code appears in:

Chamberlain Chamberlain Garage Door Opener