Sony KD-49X8005C Service Manual page 120

1) Power Off Checking*1
Power Off Check*1
Segment "XS"?
Yes
No
(1) B-PWB
PVDD-GND short ?
Yes
(See Note 1)
No
(2) B-PWB
LDO out short ?
Yes
(See Note 1)
No
(3) B-PWB
Fuse broken ?
Yes
(See Note 1)
No
Replace B-PWB
KD-49/55X8005C,XBR-55/65X800C,805C,807C,809C,810C
Note 1:
(1) PVDD-GND short check
Measure impedance between PVDD and GND at C7706,
C7707.
If impedance is <100Ω → NG
(2) LDO out short check
Measure impedance between +3.3V and GND at C9130.
If impedance is <100Ω → NG
(3) Fuse open check
Measure impedance of fuse F7700, F7702 5A (12.5V)
If fuse open → NG
(1) K-PWB
PVDD-GND short ?
Yes
(See Note 2)
No
(2) K-PWB
LDO out short ?
Yes
(See Note 2)
No
(3) K-PWB
Fuse broken ?
Yes
(See Note 2)
No
Note 2:
(1) PVDD-GND short check
Measure impedance between PVDD and GND at C7722, C7762, C7782,
C7834.
If impedance is <100Ω → NG
(2) LDO out short check
Measure impedance between +3.3V and GND at
C7909.
If impedance is <100Ω → NG
(3) Fuse open check
Measure impedance of fuse
F7702, F7704, F7705, F7701 5A (12.5V)
F7700 3.15A (DDC5V)
If fuse open → NG
Power Off Check*3
Measure the Speaker
impedance by multi-meter
Less than 3Ω ?
Confirm the speaker
Cut or shorted
to the chassis ?
Return to LED 3x blinking
Replace K-PWB
or Power Off Checking*3
TROUBLE SHOOTING
Replace Speaker
Yes
No
harness
Replace Speaker Harness
Yes
No
120