Mitsubishi Electric · PWFY Air Conditioners
This error code indicates a detected issue with the heat sink temperature sensor (THHS). This could be due to a short circuit (indicating a high temperature) or an open circuit (indicating a low temperature), typically occurring either before or during the inverter's operation.
Click steps to track your progress.
Inspect the wiring and connector for the THHS sensor for any visible damage, wear, or loose connections.
Ensure the connector is fully and securely plugged into its port.
If the unit continues to display this error when attempting to start operation, it points towards a potential failure of the Inverter (INV) board.
A qualified service technician should perform further diagnostics and replacement if necessary.