LG BUSWLJR, Service Manual

Page: 16 / 42

- 16 - LGE Internal Use Only Copyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
TROUBLE SHOOTING
Check stand-by Voltage.
P401 3, 5, 6pin : +3.5V_ST
Check Power connector
Main B/D 3.5V Line
Short Check
Check X101 clock
24 MHz
Replace X101
Check P401 PWR_ON.
1pin : 3.3V
Replace Mstar(IC101) or Main board
Check Multi Voltage
P401 9pin:24V ,13pin:12V
Replace Power Board
Check Inverter Control
P401 2 pin : High
Check Power Board or Module
Check IC403/4 Output Voltage
IC403 : 1.15V / IC404 : 1.5V
Q406 : 3.3V
Replace IC403/4, Q406
Re-download software.(IC102, IC1300)
Check Micom Voltage
L206 : +3.3V (AVDD_NODIE)
Replace L206
Check LVDS Power Voltage
Q405 : 12V
Replace Q405
Check Mstar LVDS Output
Replace Mstar(IC101) or Main Board
Change Module
ok
ok
ok
ok
ok
ok
ok
ok
ok No
No
ok
Replace Power board.
ok
No
No
No
No
No
No
No
No
1. Power-up boot check