Trouble Shooting Guide - LG 42LK450 Service Manual

Trouble shooting guide

1. Power-up boot check
Check stand-by Voltage.
P403 9~12pin : +3.5V_ST
ok
Check Micom Voltage
IC1002 pin 48 : +3.5V
ok
Check X1002 clock
32 KHz
ok
Check P403 PWR_ON.
1pin : 3.3V
ok
Check Multi Voltage
P403 2pin:20V or 24V ,17pin:12V
ok
Check IC402/3/5/6/7/10 Out Voltage
IC402 : 2.5V
IC403 : 1.26V
IC405 : 3.3V
IC406 : 6V
IC407 : 1.5V
IC410 : 5V
ok
Check X201 Clock
24 MHz
ok
Check LVDS Power Voltage
Q409 : 12V
ok
Check Mstar LVDS Output
ok
Check Inverter Control & Error Out
P403 18 pin : High
P403 24 pin : low
ok
Change Module
Copyright ⓒ 2011 LG Electronics. Inc. All right reserved.
Only for training and service purposes
No
Check Power connector
No
Replace L404
No
Replace X1002
No
Re-download Micom software.
No
Replace Power Board
No
Replace IC402/3/5/6/7/10
No
Replace X201
No
Replace Q409
No
Replace Mstar(IC101) or Main Board
No
Check Power Board or Module
ok
Main B/D 3.5V Line
Short Check
No
Replace Micom(IC1002) or Main board
※ When the PCB is EAX63529602
IC406 : 5V
IC410 : N/A
ok
Replace Power board.
LGE Internal Use Only