CodeRegistry
Brands
  1. Home
  2. Mitsubishi Heavy Industries
  3. Air Conditioners
  4. E2 / Indoor Red LED 1 flash
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.

E2 / Indoor Red LED 1 flash

Error E2 / Indoor Red LED Flashes once — Indoor unit address duplication or too many units

Mitsubishi Heavy Industries · Air Conditioners

What does E2 / Indoor Red LED 1 flash mean?

Error E2, shown by a single flash of the indoor unit's red LED, indicates that an indoor unit's address is duplicated or more than 49 indoor units are connected to the network, which exceeds the maximum limit.

Common Causes

  • Duplication of indoor unit address
  • More than 49 indoor units are connected on a network

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Consult the system installation manual to review and correct indoor unit address settings.

  2. 2

    Ensure each indoor unit has a unique address assigned.

  3. 3

    If more than 49 indoor units are present, the system configuration needs to be adjusted by a professional.

  4. 4

    Turn off and then on the main power supply after making any address changes.

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