No Sound (Power Off Check); No Sound (Power On Check) - Sony X900E Series Service Manual

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3-2. NO SOUND (POWER OFF CHECK)

Power Off Check
From 2.2 LED BLINKING 3X
(AUDIO ERROR)
Yes
(1) B board
PVDD-GND short ?
No
Yes
(2) B board
LDO out short ?
No
Yes
(3) B board
Fuse broken ?
No
Replace B board
Speaker Impedance
Rated Impedance
KP woofer
KP front
KS/KH
XBR-49/55/65/75X900E
Power Off Check
From NO SOUND
Measure the Speaker
Yes
impedance by multi-meter.
NG value of
right table?
No
Confirm the speaker
Yes
harness
Cut or shorted
to the chassis ?
No
Return to
2.2 LED BLINKING 3X
(AUDIO ERROR)
or NO SOUND
NG Value
4ohm less than 3.2ohm
6ohm less than 4.8ohm
8ohm less than 6.4ohm

3-3. NO SOUND (POWER ON CHECK)

Replace Speaker
Replace Speaker Harness
TROUBLE SHOOTING
PVDD (POWER_AU) voltage is
240W AC Adaptor model
Power On Check
200W AC Adaptor model
From 2.2 LED BLINKING 3X
Built-in power supply model : 12.5V
(AUDIO ERROR)
Measurement point is same as (1) PVDD-GND
short check.
(4) PVDD check
Yes
PVDD is supplied to
B board for a moment
No
before LED 3x blinking ?
No
Yes
Replace Power-Supply *
OK ?
No
Return to 2.2 LED BLINKING 3X
(AUDIO ERROR)
*Power-Supply is
AC Adaptor model : JK board & AC Adaptor
built-in power supply model : G board
: 24.0V
: 19.5V
Finish
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