E6/E7 - The indoor and outdoor units are not communicating properly.
Mitsubishi Electric lists E6 and E7 together as an indoor/outdoor unit communication error. That usually means the system cannot reliably exchange control or status signals between the indoor and outdoor sections.
Applies to the PEAD-M50-140JAA installation-manual family; installed controller wording can vary slightly by model.
Severity
High
Display
Shown as check code E6 or E7 on the wired remote controller. On supported self-check patterns, three beeps/flashes map to E6/E7.
Support first?
Often not
Models in range
PEAD-M50JAA(D), PEAD-M60JAA(D), PEAD-M71JAA(D)
What to do first
Start with these checks
- 1Switch the unit off at the controller and isolate power if safe to do so, then restart after a short wait.
- 2If accessible, check whether the outdoor unit has power and is not obviously shut down.
- 3Arrange service if the code remains after restart.
Likely causes
What usually sits behind this code
Interconnecting control wiring fault
Loose terminal connection between indoor and outdoor units
Outdoor or indoor control-board communication fault
Power or polarity issue affecting communications
Contact support
Contact customer support if any of these apply
- !E6 or E7 persists after a restart
- !The indoor unit runs but the outdoor unit does not start
- !The controller is unresponsive or other communication faults appear
- - The official table combines E6 and E7 under the same communication-error meaning.
- - Communication-related faults can overlap with outdoor-unit-specific errors in the same manual.
Related codes
Nearby codes in this family
More ranges
More Mitsubishi Electric air-conditioner ranges
Source notes
Source and scope
Source: Mitsubishi Electric Australia installation manual
The PEAD-M50-140JAA installation manual lists E6 and E7 as 'Indoor/outdoor unit communication error'.
Last reviewed: 2026-04-19
This entry reflects Mitsubishi Electric's official code description, but the precise failed board, cable, or terminal still needs hands-on diagnosis.