Electronic Parts Troubleshooting Guide - LG AS-C076QLA0 Service Manual

Electronic Parts Troubleshooting Guide

1. Product does not operate at all.
(* Refer to Electronic Control Device drawing and Schematic diagram.)
Check the voltage of power(About AC 220V, 60Hz)
• Main power's voltage
• Voltage applied to the unit
• Connecting method of Indoor/Outdoor connecting
cable
• Check PWB Assembly
- Fuse
- Pattern damage
- Varistor(ZNR01J)
Check the connection housing for contacting
• Connector related to CN-TAB1, RY-COMP NO.3
• Connector related to CN-MOTOR
• Connector contacting of Outdoor Fan/Compressor
• Display PWB Assembly Check
Items
• SMPS Transformer
(Indoor unit)
- Input Voltage
- Output Voltage(ZD02D)
• IC04D(7805) Output
(Indoor/Outdoor unit)
• IC01A(KIA7036, Reset IC)
X01(8MHz)
Does "beeping" sound is made from the Indoor Unit?
NO
(About AC 220/240V, 50Hz)
Main PCB Board Operation Check
- About AC220V/240V ± 10% - Check the power voltage
- About DC12V
• DC + 5V
• Voltage of Micom No. 2,
(DC +4.5V over) and Soldering condition.
Turn off Main Power
(After 10 seconds)
Turn on Main Power
Primarily, the operating condition of Micom is OK.
Check each load(Indoor/Outdoor Fan Motor,
Compressor, Stepping Motor) and contacting
condition of related connector
Content
-42-
YES
Remedy
• Replace Trans
• Replace IC04D
• Replace faulty parts