Sony A1E Series Service Manual page 30

FLOW
3-2. NO SOUND (POWER OFF CHECK)
Power Off Check
From 2.2 LED BLINKING 3X
(DC ALERT AND AUDIO ERROR)
Yes
(1) DKA board
Fuse broken ?
No
Yes
(2) DKA board
PVDD-GND short ?
No
Yes
(3) DKA board
LDO out short ?
No
Replace DKA board
(1) Fuse open check
Measure impedance of fuse F3202, F3203, F3204 5A (12.5V)
If fuse open  NG
(2) PVDD-GND short check
Measure impedance between PVDD and GND at capacitor C3305.
If impedance is <100Ω  NG
(3) LDO out short check
Measure impedance between +3.3V and GND at C3372.
If impedance is <100Ω  NG
XBR-55/65A1E
Power Off Check
From NO SOUND
Measure the SWF
Yes
impedance by multi-meter
Less than 3Ω ?
No
Measure the Speaker
Yes
impedance by multi-meter
Panel module
Less than 3Ω ?
No
Confirm the speaker
Yes
harness
Cut or shorted Speaker Harness
to the chassis ?
3-3. NO SOUND (POWER ON CHECK)
Power On Check
From 2.2 LED BLINKING 3X
(4) POWER_AU* check
Replace
POWER_AU is supplied to
SWF
DKA for a moment
before LED BLINKING 3X ?
Replace
Replace G* board
Replace
Return to LED BLINKING 3X
TROUBLE SHOOTING
*Power_AU is same as PVDD
Yes
No
No
Yes
OK ?
No
Finish
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