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A5

A5 — No ACK error (M-NET Remote controller only)

Mitsubishi Electric · MXZ Air Conditioners

What does A5 mean?

This M-NET remote controller error means that a device on the network did not acknowledge receiving a transmission (No Acknowledge). This indicates a failure in communication with a specific networked component.

Common Causes

  • A faulty device on the M-NET network.
  • Incorrect addressing for a device.
  • Broken or interrupted communication line.
  • Power issue to a specific networked device.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Check the power supply to all devices connected on the M-NET network to ensure they are powered on.

  2. 2

    Verify the address settings for all devices to ensure they are unique and correctly configured.

  3. 3

    Inspect the M-NET communication wiring for any breaks, shorts, or loose connections along the network.

  4. 4

    Power cycle the entire M-NET system after verifying connections and addresses.

  5. 5

    If the error persists, a qualified technician should investigate the specific devices on the network for responsiveness.

Browse all codes in this manual (40)
Verified technical data. Last updated: April 2026

Related Faults

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Source: Mitsubishi Electric MXZ Air Conditioners
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