Carrier DHMSHAQ09XA1 Service Manual page 26

DIAGNOSIS AND SOLUTION (CONT)
IPM malfunction or IGBT over−strong current protection diagnosis and solution (P0)
Error Code
Malfunction decision conditions
Supposed causes
Troubleshooting
Check the wiring between main the
PCB and the compressor
Check the IPM
Check the outdoor fan and the
outdoor unit ventilation
Check the compressor resistance
Replace the outdoor main PCB
P0
When the voltage signal, that the IPM sends to the compressor drive chip is abnormal, the display
LED displays P0"and the air conditioner turns off.
·Wiring mistake
·IPM malfunction
·Outdoor fan assembly faulty
·Compressor malfunction
·Outdoor PCB faulty
No
Yes
Yes
values
Yes
Correct the connection or replace
Yes
the wires and connectors.
Replace the IPM board or replace
No
the main PCB
Please refer to the solution of
No
Speed Has Been Out Of Control
malfunction
No Replace the compressor.
26
Fan