LG CM4520 Service Manual page 37

AUDIO ELECTRICAL TROUBLESHOOTIHG GUIDE
No 12 V
YES
Is Vcc
(15 V) supplied to Q953
collector?
YES
Is the
13 V Supplied to Q953
base?
YES
Check or replace Q953.
No 5 V
YES
Is Vcc
(6 V) supplied to IC951
Pin1?
YES
Check
IC951 Pin4 "H".
YES
Check or replace IC951.
NO
Check or replace D921.
NO Check P-CTRL "H" signal
from μ-COM.
NO
Check or replace D923.
NO Check P-CTRL
"H"' signal from μ-COM.
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