Midea MCD-48HRFN1-M(D) - Inverter Compressor Drive Error Diagnosis and Solution

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17.4.11 Inverter compressor drive error diagnosis and solution(P4)
Error Code
P4
Malfunction conditions
Abnormalities in the inverter compressor drive is detected by a
special detection circuit, which can perform communication
signal detection, voltage detection, and compressor rotation
speed signal detection.
Potential causes
● Wiring mistake
● IPM malfunction
● Faulty outdoor fan assembly
● Compressor malfunction
● Faulty outdoor PCB
Trouble shooting:
Check the wiring between the main
PCB and compressor. Is it improperly
wired?
Ensure proper connection or
replace the wires and connectors
Yes
No
Check the IPM. Is it functioning
properly?
No
Yes
Replace the IPM board or replace
the main PCB
Check the outdoor fan and the
outdoor unit ventilation. Is it
functioning properly?
No
Please refer to “Fan Speed
Malfunction”
Yes
Check the compressor resistance
values. Are they within acceptable
parameters?
No Replace the compressor
Yes
Replace the outdoor main PCB