Sony BRAVIA KDL-55W900A, Service Manual

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RB1G
CHASSIS
W900A/904A/905A
Troubleshooting
3-3-4. Main Board Power On Checking (for Main SP Lch & Rch)
No Checking Item OK NG If

NG If

NG
1 Check Switching Freq = 384kHz or No switching Go to next checking. 1 Check
IC4601 side-terminal of
L4601,L4602,
L4603,L4604 Switching Freq 384kHz or
768KHz ±20KHz
Vrms = dont care No switching
frequency at
either one of the
CL Go to next checking.
2 Check F4601 MainSP
(for BA2 and BM board
only) V(before fuse) = 12.5V ± 0.5V
V(after fuse) = 12.5V ± 0.5 V No voltage. Check fuse broken?
Check CN9101 Pin 8
&10 got 12.5V? Change fuse (5A).
Check power supply
board audio VCC.
3 Check F4601 MainSP
(for BKE and BKX V(before fuse) = 19.5V ± 0.5V
V(after fuse) = 19.5V ± 0.5 V No voltage. Change fuse (5A).
Check power supply
(
board only) ( ) p pp y
board audio VCC.
4 Check IC4601 (Pin
8) and C4601 (Pin 27)
(for BKE and BKX
board only) V(before fuse) = 3.3V ± 0.5V
V(after fuse) = 3.3V ± 0.5 V No voltage. Check +3.3V_MAIN
supply.
Size B* Board Type G* Board
Type
OTHERS JP
40” BA2-S BA2-W G1A
Note:
86
46” BA2-S BA2-W G1A
55” BA2-S BA2-W G1B
Note:
(AYU2) – IC9000
(Brownie)- IC9001