LG ARWN038GA2 Service Manual page 74

Troubleshooting Guide
Error No. Error Type
AC input instant over cur-
73*
rent error (Matter of soft-
ware)
■ Error Diagnosis and Countermeasure Flow Chart
Is installation
condition normal?
Yes
Is input voltage normal?
Yes
Is AC input Wire connection
condition normal?
Yes
Is compressor
Wire connection
condition normal?
Yes
Is inverter PCB assembly
normal?
Yes
Recheck power and
installation condition
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Error Point
Inverter PCB input 3 phase power
current is over 50A (peak) for 2ms
1.Check Pipe clogging/distortion
2.Check Covering (Indoor/outside Unit)
No
3.Check EEV connector assemble condition/normal operation
4.Check refrigerant pressure
' Reassemble or manage if abnormality found
Check
No
R~S / S~T / T~R phase voltage is 380V 10%
R~N / S~N / T~N phase voltage is 220V 10%
→ Check connection condition and wiring if power is abnormal
1.Check L (L1), N (L2) connection condition
No
2.Check wire disconnection and wiring
→ Reassemble if abnormality found
1.Check inverter PCB assembly U,V,W connector connection condition
No
2.Check wire disconnection and wiring
3.Check compressor terminal connection condition(bad contact)
→ Reassemble if abnormality found
No
Check inverter PCB assembly IPM normality
→ Replace inverter PCB assembly
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Main Reasons
1.Overload operation (Pipe clog-
ging/Covering/EEV defect/Ref.
overcharge)
2.Compressor damage (Insulation
damage / Motor damage)
3.Input voltage abnormal
4.Power line assemble condition
abnormal
5.Inverter PCB assembly damage
(input current sensing part)
LGE Internal Use Only