- 19 - LGE Internal Use OnlyCopyright © LG Electronics. Inc. All rights reserved.
Only for training and service purposes
TROUBLESHOOTING GUIDE

1. Check the booting Voltage

Make sure the Stand-by Voltage.
P401 3, 5pin : +3.5V_ST
Make sure the Micom voltage.
L301 : +3.5V_ST
Make sure the output of MSTAR
LVDS.
Make sure the Multi Voltage.
P401 9, 10pin : 24V, 13~15pin : 12V
Make sure the CLK of X300
Is 10MHz.
Make sure the CLK of X300 is
10MHz.
Exchange the LCD Module.
Make sure the Output Voltage of IC
402/3/7.
IC402 : 2.5V, IC403: 1.1V, IC407 :
1.5V, Q403 : 3.3V
Push Micom Reset(SW300) and
make sure the PWR_ON
P401 1pin : 3.3V
Make sure the voltage of LVDS
Power.
Q409 : 12V
Make sure the Power
Connector.
Exchange the L301.
Exchange the Mstar(IC101
or Main board.
Exchange the circuit
board.
Exchange the X300.
Exchange the circuit or
check the LCD module.
Exchange the
IC402/3/7, Q403.
Re-download of
Firmware.
Exchange the Q409.
Make sure the disconnection of
Main board 3.5V circuit.
Exchange the Mstar(IC101)
Or Main board
Exchange the
Circuit board.
No
No
No
No
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No