Midea MSR1-24HRDN1-QC2W Service Manual page 33

Does compressor
operate?
YES
Is refrigerant
circulation
volume normal?
NO
Charge refrigerant
Is abnormality
the same after
gas charging?
NO
9.2.8 P4(inverter compressor drive error) diagnosis and solution.
Is the connection of
compressor good? Is the
wiring sequence right? The
voltage range proper?
Replace the outdoor E-box.
If the problem comes to
again, check coil resistance
of inverter compressor, is it
right?
NO
Is the connection
good?
Is protector
normal?
Check the outdoor
main PCB. Is there
some problem?
YES
NO
YES
NO
YES
YES
NO
NO
Reconnect and retest.
Replace the protector.
Replace the outdoor PCB.
Check refrigerant system (such
as clogging of capillary, etc)
Reconnect and retry
Replace inverter compressor
31