Mitsubishi Electric · FR-D700 Inverter
A transmission error has occurred between the inverter and the outdoor unit PCB, possibly due to a loose connection at the 'Cal' terminal. This disrupts critical communication and control signals.
Click steps to track your progress.
Inspect the communication wiring between the inverter and outdoor unit PCB for secure connections.
Verify the connection at the 'Cal' terminal on the outdoor unit PCB, ensuring it is tight and corrosion-free.
Check for signs of damage or corrosion on the communication terminals themselves.