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A2

A2 - 2 red flashes, 5 green flashes — Hardware error of transmission processor (Lossnay)

Mitsubishi Electric · Air Conditioning

What does A2 mean?

This fault indicates a hardware error within the transmission processor of a Lossnay unit. Check the communication wiring and the unit's board.

Common Causes

  • Faulty communication wiring
  • Hardware error on the Lossnay board
  • Noise interference on communication lines

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Inspect the communication wiring for damage or loose connections.

  2. 2

    Check the connections on the Lossnay board.

  3. 3

    Ensure there is no excessive electrical noise near the communication lines.

  4. 4

    Consider a possible fault with the Lossnay board itself.

Browse all codes in this manual (170)
Verified technical data. Last updated: April 2026

Related Faults

0.5-second ON / 0.5-second OFF blinkUpper lamp blinks 0.5-second ON/OFF - Miswiring or serial signal error00Normal operation - No error codes1 beep during error display mode1 beep during error display mode - Unit has an error (different code)
Source: Mitsubishi Electric Air Conditioning
Open Manual (Page 16)Search more codes in this manual