No Power Ddcon/Ldo - Sony X900E Series Service Manual

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1-3. NO POWER DDCON/LDO

DDCONs CHECK ON JK*
START
Check fuse
no
F9001
Is fuse OK?
yes
Check Vcc voltage
no
C9023
Is voltage >18V?
yes
Check Enable pin
no
voltage
Is voltage >2.5V?
yes
Change DDCON IC
XBR-49/55/65/75X900E
Change Fuse
No Power U-Com Failure
NG
(Both side are No power.)
Check
F9000
On JK* board
NG
(Only single side is
OK
19.5V or 24V.)
(Both side are
19.5V or 24V.)
Q9002 or
drive circuit around Q9002
on JK* board
TROUBLE SHOOTING
AC Adaptor
F9000
IC Ref Voltage supply
IC9000 +12V_MAIN
23