Carrier 40MBFAQ Service Manual page 26

40MBFAQ: Service Manual
DIAGNOSIS AND SOLUTION (CONT.)
PC 04 (Inverter compressor drive error Diagnosis and Solution)
Description: An abnormal inverter compressor drive is detected by a special detection circuit, including a communication
signal detection, voltage detection, and compressor rotation speed signal detection.
Recommended parts to prepare:
• Connection wires
• IPM module board
• Outdoor fan assembly
• Compressor
• Outdoor PCB
Troubleshooting
NOTE: For certain models, the outdoor PCB cannot be removed separately. In this case, the outdoor electric control box should be replaced
as a whole.
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
Check the wiring between the
PCB and compressor.
Is it improperly wired?
NO
Check the IPM.
Is it functioning
properly?
YES
Check the outdoor fan and
the outdoor unit ventilation.
Is it functioning
properly?
YES
Check the compressor
resistance values.
Are they within
acceptable parameters?
YES
Replace the outdoor PCB.
Ensure proper connections or replace
YES
the wires and connectors.
Replace the IPM board or
NO
replace the outdoor PCB.
Refer to "Fan Speed"
NO
Malfunction.
NO Replace the compressor .
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