Electronic Parts Troubleshooting; Electronic Parts Troubleshooting Guide - LG Universal System Air Conditioner Service Manual

Troubleshooting Guide

3. Electronic Parts Troubleshooting Guide

❇ Refer to electronic contorol device drawing & schematic diagram.
Trouble 1
Check the voltage of power(AC220V/AC240V, 50Hz).
• The voltage of main power.
• The voltage applied to the unit.
• The connecting method of Indoor/Outdoor connecting cable (each color)
• The P.W.B. Ass'y
(Fuse, Noise Filter, Power Transformer, IC01D, IC02D, etc.)
The operation check of the P.C.B. Ass'y
Procedure
1) The input voltage of power trans-
former.
2) The output voltage of power
transformer.
3) IC01D(7812)
4) IC02D(7805)
5) IC01A(KIA7036)
82 Universal System Air Conditioner
The Product doesn't operate at all.
Turn off the main power and wait until LED on outdoor PCB is off.
Turn on the main power again.
Does "Beeping" sound is made from the indoor unit?
NO
1) AC230V ± 30V
: Check the rated voltage
2) 14V ± 3V
3) DC12V
4) DC5V
5) The voltage of micom pin 29
: DC4.5V↑
Specification
YES
• Primarily, the operating condi-
tion of Micom is O.K.
• Check CN-DISP1
Remedy
1) Replace
power transfomer.
2) Replace
power transfomer.
3) Replace IC01D.
4) Replace IC02D.
5) Replace IC01A.