Panasonic CS-VZ9SKE Service Manual page 131

17.4.30 F96 (Transistor Module Over-temperature Protection)
Troubleshooting
Check if the ventilation of the outdoor unit is interrupted by dust, etc.
Check if the heat radiation by the heat sink of the outdoor unit control board
is interrupted by dust, etc.
Diagnosis Procedures and Cause
No abnormality is observed
Heat radiation is not interrupted
Ventilation is
interrupted
Heat radiation
is interrupted
131
Measures to be Taken
Fix the problem.
Fix the interrupted heat radiation
problem.
Replace the outdoor unit control board.