Haier 1U71S2SG1FA Service Manual page 237

[4] Communication Failure Between Module Ans Ecu
Check if wire between
PCB and power module is
Check if communication
abnormal(if signal LED
flashes abnormally)
If power module is
abnormal
Solve the failures due
to relative information
[5] Module Operated Overload
Check if voltage of power
supply is normal
Check if wiring of
electric box is correct
normal(compressor coil
resistor, insulation)
Compressor load too
much,check the reason
abnormal
N
circuit of PCB is
N
N
Y
Y
If compressor is
Y
If power module is
normal
Y
Y
Adjust communication wire
Y
Replace PCB
Y
Replace power module
N
Improve power supply circuit
N
Correct the wiring due to diagram
N
Replace compressor
N
Replace power module
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