Lg Electronics LA120CPO 사용자 설명서

Turn off Main Power

Turn on Main Power

Does "beeping" sound is made from the Indoor Unit?

Primarily, the operating condition of Micom is OK.

Check the voltage of power(About AC 115V, 60Hz)

• Main power's voltage
• Voltage applied to the unit
• Connecting method of Indoor/Outdoor connecting

cable

• Check PWB Ass'y(Outdoor unit)

- Fuse
- Pattern damage
- Varistor(ZNR01J)

Check the connection housing for contacting

• Connector related to CN-POWER
• Connector related to CN-FAN
• Connector contacting of Outdoor Fan/Compressor
• Display PWB Ass'y Check
• Connector related to CN-DC/DC

Check each load(Indoor/Outdoor Fan Motor,
Compressor, Stepping Motor) and contacting 
condition of related connector(including connecting
cable of Indoor/Outdoor Unit)

PCB Board Operation Check

Items

• Power Transformer

(Outdoor unit)
- Input Voltage
- Output Voltage

• IC01D(7812) Output

(Indoor/Outdoor unit)

• IC02D(7805) Output (Indoor unit)

IC03D(7805) Output (Outdoor unit)

• IC01A(KIA7036, Reset IC)

OSC01B(4MHz)
(Indoor/Outdoor unit)

• Replace SMPS

Module

• Replace IC01D

• Replace

IC02D(Indoor unit)
IC03D(Outdoor unit)

• Replace faulty parts

- About AC115V±10% - Check the power voltage
- About DC15V±3

• DC +12V

• DC +5V

• Voltage of Outdoor unit Micom No. 18, 

Voltage of Indoor unit Micom No. 43 and 
soldering condition

Content

Remedy

NO

YES

(After 20 seconds)