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TROUBLESHOOTING
4-2. Troubleshooting by symptom
4-2-1. When there is no power at Inverter PCB (F Room Inverter, LC3-3A)
Is the power plug connected?
Is the CN101, 102 Connector inserted
correctly?
Has AC 120V been applied to CN102
①-③?
Is the FUSE on the Inverter PCB
blown?
Has DC 310V applied to both ends of
the BD1+,-?
Is DC 13.2V applied to C121 or T1⑥-
①?
Is DC 15V applied to C108?
Is DC 5V applied to C111?
Is DC 5V applied to C118?
Is the Panel PCB working normally?
Has any of the soldering on the PCB
been short-circuited or open-
circuited?
Connect the power plug again and check
if the connection between the power outlet
and the power plug is loose
If the connector is connected incorrectly,
connect it properly (CN101,102)
Check the assembly and wire connections
Replace Fuse (AC 250V 2.0A)
Replace the Inverter PCB
Replace the Inverter PCB
Replace REG1 (7815)
Replace REG2 (5V LDO)
Replace REG3 (5V LDO)
Check the wire harness
Replace the PANEL PCB
Replace the Inverter PCB
Normal (Recheck)
No.
No.
No.
Yes
No.
No.
No.
No.
No.
No.
No.
Yes
Yes
Yes
No.
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Start
AC120V and DC170V flow
on the Inverter PCB Power
Circuit. Therefore, please be
careful when repairing the
unit or measuring values.
Caution
- To check the Inverter PCB,
refer to the 'Operations' and
'Refer' sections in this manual
The voltage checking method
AC120V: CN102 ① ↔ ③
The voltage checking method
DC 13.2V: T ① ↔ ⑥
Check with the Inverter
PBA
- Check the Main PCB wires.
- Check the Door Panel PCB
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