LG Multi-Inverter Type, Service Manual

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4. Trouble Shooting
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Copyright ©2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
05
/
53
Title
Communication
(Indoor
→
Outdoor)
• Communication poorly
• Power input AC 220V. (Outdoor, Indoor)
• The connector for transmission is disconnected.
• The connecting wires are misconnected.
• The communication line is shorted at GND.
• Transmission circuit of outdoor PCB is abnormal.
• Transmission circuit of indoor PCB is abnormal.
Display
code
Title Cause of error Check point & Normal condition
Check Point
1. Check the input power AC230V. (Outdoor, Indoor unit)
2. Check the communication wires are correctly connected.
Adjust the connection of wire Confirm the wire of "Live",
"Neutral"
3. Check the resistance between communication line and
GND. (Normal : Over 2M
Ω
)
4. Check the connector for communication is correctly con-
nected.
5. If one indoor unit is operated normally, outdoor PCB is no
problem.
Check the another indoor unit.
* CH05 is displayed at indoor unit, CH53 is displayed at
outdoor unit.
6. If all indoor unit is displayed CH05 but outdoor PCB not
display
CH53 : Check the CN_COM and CN_POWER is correctly
connected.
• 27/30/40k
1. In Case of CH53, Check the Connection
→
L , N at the ter-
minal block
• 48/56k
1. In Case of CH05, Check the Connection
→
CN-POWER,
CN-COMM at the Main PCB
2. In Case of CH53, Check the Connection
→
CN-COMM at
the Main PCB
→
L , N at the terminal block
▶ ▶
A4UW276FA3/A5UW306FA3/A5UW406FA3/A7UW406FA3/A8UW486FA3/A9UW566FA3
< TERMINAL BLOCK >
< MAIN PCB >
L N
N
L
N
L N
CN-Power
CN-COMM