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Red check indicator flashing + Error code

Red check indicator light flashing and error code displayed — Air conditioner stopped due to trouble

Mitsubishi Heavy Industries · Packaged Air Conditioners

What does Red check indicator flashing + Error code mean?

When the air conditioner encounters an issue, it stops operating. The red check indicator light on the wired remote control will flash, and an error code will be shown in the ON timer display area, along with 'STANDBY' and the 'ROOM TEMPERATURE' display. If multiple units are connected, the lowest numbered unit's error displays first.

Common Causes

  • Internal malfunction or fault detected by the system.
  • Problem with a connected indoor unit (if multiple units are installed).

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Identify the error code displayed on the remote control. The error code will appear in the ON timer display area.

  2. 2

    If multiple indoor units are connected, press the AIR CON No. button to enter display mode, then use the up/down buttons to cycle through units and their error codes.

  3. 3

    Press the ON/OFF button once to turn off the error display and return to stop mode. Press it again to redisplay errors if needed.

  4. 4

    Note the specific error code and contact your dealer or service technician, providing them with the code for diagnosis.

  5. 5

    If the problem persists after attempting to clear the error, refrain from further operation and seek professional assistance.

Browse all codes in this manual (21)
Verified technical data. Last updated: April 2026

Related Faults

Abnormal Compressor NoiseCompressor Making Abnormal Sound or Vibrating — Indicates a serious internal issueAbnormal DisplayAbnormal Display on Electric Component Box/Control Panel — Indicates an electrical issueAbnormal Fan NoiseFan Making Abnormal Sound or Vibrating — Indicates an internal issue
Source: Mitsubishi Heavy Industries Packaged Air Conditioners
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