Pioneer YN020GMFI22M2D Service Manual page 73

8.4.2.14 P6 (Inverter module (IPM) malfunction) diagnosis and solution.
Error Code
Malfunction decision
conditions
Supposed causes
Trouble shooting:
P6
When the voltage signal that IPM send to compressor drive
chip is abnormal, the display LED will show "P6" and AC will
turn off.
● Wiring mistake
● IPM malfunction
● Outdoor fan ass'y faulty
● Compressor malfunction
● Outdoor PCB faulty