Error code
recall-serial-signal-3-blinks Failure-memory recall: serial-signal communication fault
How it shows on the unit 3 blinks, then 2.5 seconds OFF, repeating in the failure-memory recall mode
Applies to 12 models
What this means
The serial signal from the outdoor unit was not received for up to 6 minutes, indicating an indoor-to-outdoor communication or miswiring fault.
When to call a technician
This fault involves refrigerant, pressure, or electrical work that must be handled by a certified technician under EU F-gas rules. Do not attempt to open the refrigerant circuit, access mains wiring, or adjust pressure components yourself. Contact a qualified installer or servicer for this one.
See the Mitsubishi Electric manual (hosted by an authorized distributor)Hosted by an authorized distributor rather than by the manufacturer. We link to manuals, we never host them.
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