Communication Error (Indoor Unit - Main Pcb) - LG multi V PLUS Service Manual

Self-diagnosis function
Fault diagnosis and Trouble shooting guide
Error
Error Item
Display No.
Communication error
(indoor unit - main PCB)
53
Trouble shooting Flow
Is power supplied to all indoor units?
Are communication
lines of indoor units normal?
Is automatic addressing
performed accurately?
Is communication circuit part of the
outdoor unit normal?
Check or replace the indoor unit PCB
278 Trouble Shooting Guide
Meaning
If failing to receive
indoor unit signal at
main PCB
No
Yes
No
Yes
No
Yes
No
Yes
Major Error Occurrence Cause
• No connection of communication line
• Short or fusing of communication line
• Poor outdoor unit PCB or indoor unit PCB
Check and connect power line.
Check and connect the
communication line.
Perform automatic addressing again.
Check or replace the main PCB