LG MULTI V 5 Manual Book page 59

External PCB Main PCB
Wiring Fault Case
Copyright ©2017 LG Electronics. Inc. All right reserved.
Only for training and service purposes
116
_TROUBLE SHOOTING GUIDE BOOK
Indoor Unit
Communication PCB
- 132 -
LGE Internal Use Only
Error
Error Type Error Point
No.
Error No. Error Type Error Point
57*
Failing to receive
Master 571 Failing to receive inverter
Communication er-
Communication error : Main
inverter signal at
signal at main PCB of
Slave1 572
ror : Main PCB →
57*
PCB --> Inverter PCB
main PCB of Out- Outdoor Unit
Slave2 573
Inverter PCB
door Unit
Slave3 574
n Error diagnosis and countermeasure flow chart
Are there any
No
communication wire 1. Check communication wiring conditions
connections normal? 2. Check connector conditions
→ Rewire them if abnormality found.
Yes
Is Inverter PCB
No
1. Replace Inverter PCB
assembly
normal?
Yes
Is there any error Yes
1. Replace Main PCB
when power reset?
No
Recheck power and
installation condition
Fan board Inverter PCB 1
Communication
LED
Communication
LED
Copyright ©2017 LG Electronics. Inc. All right reserved.
Only for training and service purposes
Main Reasons
Main Reasons
1. Bad Connection Between Comp PCB and
1. Bad Connection Between Inverter PCB and
Comp PCB
Comp PCB
2. Communication Wire Noise Effect
2. Communication Wire Noise Effect
3. ODU Main PCB Damage
3. ODU Main PCB Damage
4. ODU Main PCB Damage
4. ODU Inverter PCB Damage
Inverter PCB 2 Main PCB
Communication LED
Communication
LED
- 133 -
LGE Internal Use Only
117
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