CodeRegistry
Brands
  1. Home
  2. Mitsubishi Heavy Industries
  3. Air Conditioners
  4. E5 / Indoor Red LED 2 flashes
About·Privacy·Terms

CodeRegistry — Your global library for technical solutions.

For your safety: always follow the equipment manufacturer’s official manuals. CodeRegistry is an independent help site and is not affiliated with the brands listed here.

E5 / Indoor Red LED 2 flashes

Error E5 / Indoor Red LED Flashes Twice — Outdoor unit microcomputer failure

Mitsubishi Heavy Industries · Air Conditioners

What does E5 / Indoor Red LED 2 flashes mean?

Error E5, shown by the indoor unit's red LED flashing twice, indicates a failure in the outdoor unit's microcomputer. This critical component manages the outdoor unit's operations.

Common Causes

  • Outdoor unit microcomputer failure

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Perform a power reset by turning off the entire system's main power for a few minutes, then turning it back on.

  2. 2

    This error typically requires replacement of the outdoor unit's main control board.

  3. 3

    Contact a certified Mitsubishi Heavy Industries technician for inspection and repair.

  4. 4

    Avoid attempting internal repairs yourself as it may void warranties and pose safety risks.

Browse all codes in this manual (110)
Verified technical data. Last updated: April 2026

Related Faults

01Power source faulty — RUN LED OFF, TIMER LED flashes 1 time05Wired remote control wiring error — RUN LED OFF, TIMER LED flashes 5 times35Cooling high pressure control activated — RUN LED flashes 3 times, TIMER LED flashes 5 times
Source: Mitsubishi Heavy Industries Air Conditioners
Open Manual (Page 2)Search more codes in this manual