LG MULTI V IV ARNU07GTU 2 Series Service Manual page 110

Troubleshooting Guide
Error
Error Type
No.
52*
Communication error
Master 521
between
Slave1 522
(Comp1/Comp2 PCB
Slave2 523
' Main PCB)
Slave3 524
n Error diagnosis and countermeasure flow chart
Is communication
LED (Yellow) of
Comp1/Comp2 PCB
PCB on?
Yes
Is communication cable
connected correctly?
Yes
Is Main PCB normal?
Yes
Replace Comp1/Comp2 PCB
* The method of checking Main PCB and Comp1/Comp2 PCB (If normal, communication LED blinks)
Comp1 Communication
LED
Comp1 Communication
Connector
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Error Point
Main PCB of Master unit
of Master unit canʼt
receive signal from
Comp1/Comp2 controller
No
Re-connect communication cable
No
Re-connect communication cable
No
Replace Main PCB
Com2 Communication
LED
Comp2 Communication
Connector
1. Power cable or communication cable is not
connected
2. Defect of outdoor Main PCB or
Comp1/Comp2 PCB
Communication Connector &
LED in Comp1 PCB
Communication Connector &
LED in Comp2 PCB
- 110 -
Main Reasons
LGE Internal Use Only