3-11
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
MAIN PART
MAIN ELECTRICAL TROUBLESHOOTING GUIDE
No power on
by ADAPTOR
A
Replace ADAPTOR
NO
YES
1. POWER (DC-DC CONVERTER) CIRCUIT
A. POWER
Is ADAPTOR
out 9V
Replace F1
NO
YES
YES
Is F1 OK.
Replace U4
Replace
CON1 or CON2
No +3.3V
No +5V
No LCD power
No +1.8V
YES
YES
NO
Replace U4
Is U4
3.3V OK?
No power on
by BATTERY
A
Replace BATTERY
NO
YES
Is
BATTERY
OK?
YES
A