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10.12 Error Code: PC 04(Inverter compressor drive error diagnosis and solution)
Description: An abnormal inverter compressor drive is detected by a special detection circuit, including
communication signal detection, voltage detection, compressor rotation speed signal detection and so on.
Recommended parts to prepare:
•
Connection wires
•
IPM module board
•
Outdoor fan assembly
•
Compressor
•
Outdoor PCB
Troubleshooting and repair:
Check the wiring between the
PCB and compressor
Is it improperly wired?
Ensure proper connections or
replace the wires and connectors.
YES
Check the IPM.
NO
Is it functioning
properly?
Replace the IPM board or
replace the outdoor PCB.
NO
Check the outdoor fan and
the outdoor unit ventilation.
YES
Is it functioning
properly?
Please refer to “Fan
Speed Malfunction.”
NO
Check the compressor
resistance values.
YES
Are they within
acceptable parameters?
Replace the compressor.NO
Replace the outdoor PCB.
YES
Note: For certain models, outdoor PCB could not be removed separately. In this case, the outdoor
electric control box should be replaced as a whole.
****Disclaimer****
The error codes and descriptions are for reference only. If your system displays any of
these codes contact a qualified technician to investigate the matter further.