Pioneer CB009GMFILCFHD Service Manual page 99

16.3.7 IPM malfunction or IGBT over-strong current protection diagnosis and solution (P0)
Error Code
Malfunction decision
conditions
Supposed causes
Trouble shooting:
P0
When the voltage signal that IPM send to compressor drive chip
is abnormal, the display LED will show "P0" and AC will turn off.
Wiring mistake; IPM malfunction; Outdoor fan ass'y faulty
Compressor malfunction; Outdoor PCB faulty
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