LG ARUN Series, Service Manual

Page: 122 / 134

Troubleshooting Guide
- 122 -
Copyright ©2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
1.Fan motor defect/ assemble condition abnor-
mal
2.Fan motor connector misconnection(Hall sen-
sor, U,V,W ouput)
3.Fan PCB defect
Error No. Error Type Error Point Main Reasons
Fan Motor initial starting failure
Fan Starting Failure
Error
79*
Master 791
Slave 792
■
Error Diagnosis and Countermeasure Flow Chart
Is fan motor connection
condition normal?
1. Check if color of motor output terminal(U,V,W) connector matched with PCB’s
2. Check wire disconnection and wiring
→
Reassemble or replace if abnormality found
Is fan PCB assembly normal?
Yes
No
Recheck power and
installation condition
Yes
No
1. Check resistance between each motor output terminal
(16.8
Ω ±
5% at 75
°
C)
2. Check insulation resistance between ODU fan motor terminal(U,V,W) and pipe
(over 100M
Ω
)
→
Replace fan motor if abnormality found
No Are the resistance
Between each phase and insulation
resistance of motor output
terminal normal?
Check ODU fan motor assemble condition and locking
→
Reassemble or replace if abnormality found
No
Is fan motor assemble
condition normal?
Fan motor wire connection
Measuring fan motor phase
resistance
Hall Sensor connection
Check fan PCB assembly IPM normal
→
Replace Fan PCB assembly
Fan wire wiring
Measuring insulation resistance
between fan terminal & chassis