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3-6
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
No 5.0VD
Is there
about 5.3V at the IC153
pin1?
Check 5.3VA on SMPS Board
YES
YES
NO
Is there
about 4V ~ 5V at the IC153
pin4?
Check the “PWR CTL H”
signal from µ-COM
YES
NO
Check the IC153 and Replace
No 2.5V
Is there
about 3V ~ 3.8V at the IC151
pin1?
Check D154 and D123
on SMPS Board
YES
YES
NO
Is there
about 4V ~ 5V at the IC151
pin4?
Check the “PWR CTL H”
signal from µ-COM
YES
NO
Check the IC151 and Replace
ELECTRICAL TROUBLESHOOTING GUIDE