
Copyright © 2011 LG Electronics. Inc. All right reserved. - 23 - LGE Internal Use Only
Only for training and service purposes
5. POWER
Check U901,T901,D901,D906,ZD901,Q904,U902,U903
Check U901 pin 6
Vcc is 30V?
Check D904, C913
NO
YES
Check U901 PIN5
output is PWM?
Check D907, Q901
NO
Check start
voltage for the pin8
of U901
Check R908, R911, U901
YES
NO
YES
No Power
(Power Indicator Off)
Check AC line
volt
Check the
voltage of C907(+)
Check AC line
Check F901, BD901
NO
YES
NO