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Self-diagnosis function
1. Bad Connection Between Main PCB and
Inv. PCB
2. Communication Wire Noise Effect
3. ODU Main PCB Damage
Error
No.
Error Type
Error Point
Main Reasons
Failing to receive inverter
signal at main PCB of
Outdoor Unit
Communication error : Main
PCB --> Inv. PCB
57
n
Error diagnosis and countermeasure flow chart
Are there any
communication wire
connections normal?
Is Inv. PCB
assembly
normal?
Is there any error
when power reset?
Recheck power and
installation condition
1. Check communication wiring conditions
2. Check connector conditions
→
Rewire them if abnormality found.
1. Replace Inv. PCB
1. Replace Main PCB
No
No
No
Yes
Yes
Yes
Inv. PCB
Main PCB