Mitsubishi Multi Communication System Reset

Do not just press the "Stop" button on the remote. Go to the electrical panel. Turn off the dedicated circuit breaker for the outdoor unit AND the indoor unit(s). You must kill power to the entire M-Net network.

Resetting the Mitsubishi Multi Communication System (MMCS) ranges from a quick 10-second reboot to a full factory wipe, depending on the severity of the issue. mitsubishi multi communication system reset

Press and hold Settings and Map buttons together for 4 seconds. Do not just press the "Stop" button on the remote