LG RN7 - Page 44

No PVDD
YES
F901 normal?
Replace F901 (Use the same fuse).
YES
NO
BD901 normal? Replace BD901.
YES
YES
NO
TH901 normal?
Replace TH901.
YES
YES
NO
Is Vcc
(10 V ~ 18 V) supplied to
IC901 pin2?
D903 normal?
YES
NO
Check or replace D903.
• Check P_CTRL HIGH signal from MCS.
• Check PC902.
Q901 normal? Replace Q901.
Check or replace Q911.
YES
NO
D951 normal?
Replace D951.
YES
NO
Is there about 2.5 V
at IC951 pin1?
Replace IC951.
YES
NO
Q911 base HIGH?
Power line of main PCB is short.
NO
NO
Model PVDD Fuse FET
ON5/ RN5 34 V 5 A Q901
ON7/ RN7 47 V 5 A Q901
ON9/ RN9 58.5 V 8 A Q901, Q902
POWER (SMPS)
3-17
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