Everwell MKTH1223E-16 - 3.2.17 Troubleshooting P9: Compressor Drive Protection

Air Conditioner Service Manual
46
3.2.17 P9---The compressor driving protection (the compressor load abnormal)
When compressor start up or in the process of operation, if:
(1). MCU can’t test the feedback signal from compressor, or
(2). Tested a abnormal signal from compressor, or
(3). The compressor startup abnormal.
The outdoor unit will shut off, and show P9 protection.
(The unit will re-startup 6 times continuously, if it still can’t work normal, then show P9 code)
Display P9
Normal protection as the
High pressure and Low
pressure not balance.
End
Check the compressor
wires U/V/W sequency
& connection,
CORRECT?
No
Yes
No
Starts up the unit less than
3 minutes while it stopped?
The compressor stops at
once while it starts up
Yes
Re-correct wires
Replace ODU PCB
Still P9?
Still P9?
Yes
No
No
Yes
Re-start after
3minutes