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3-6
Copyright © 2008 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 Pin 1?
Check 5.3VA on SMPS board
YES
YES
NO
Is there about 4V ~ 5V at
the IC153 Pin 4?
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 Pin 1?
Check D154 and
D127 on SMPS board
YES
YES
NO
Is there about 4V ~ 5V at
the IC151 Pin 4?
Check the “PWR CTL H”
signal from µ-COM
YES
NO
Check the IC151 and replace
No 3.3V
Is there about 3.8V at
the IC152 Pin 1?
Check D127 on SMPS
board and replace
YES
YES
NO
Is there about 4V ~ 5V at
the IC152 Pin 4?
Check the “PWR CTL H”
signal from µ-COM
YES
NO
Check the IC152 and replace