Pioneer VSX-820-K Service Manual page 31

5
QQ
3 7 63 1515 0
Step 2: Power supply
CN701 (Pin 1)
Is the voltage
0 to 3.3 V?
Yes
CN701 (Pin 9)
Is the voltage
3.3 V?
Yes
CN701 (Pin 12)
Is the voltage
5 V?
Yes
CN701 (Pins 13, 14)
Is the voltage
TE
L 13942296513
3.3 V?
Yes
Q711 (collector)
Is the voltage
3.3 V?
Yes
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SUB_ON
No
Diagnose the MAIN Assy.
SUB MICOM 3.3V
No
Diagnose the MAIN Assy.
HDMI_5V
No
Diagnose the MAIN Assy.
HDMI_3.3V
No
Diagnose the MAIN Assy.
SUB MICOM 3.3V
Is Q711
No No
base voltage
2.6 V?
Yes
Check the parts and
patterns in the path.
Replace Q711,
IC706, etc.
Is Q714
No
Replace Q714.
collector voltage
0 V? (base is 3.3 V)
Yes
Check the parts and
patterns in the path
Q711, Q714, etc.
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7
2 9
8
IC704 (Pin 3)
Is the voltage
3.3 V?
Yes
IC704 (Pin 2)
Is the voltage
1.8 V?
Yes
IC701 (Pin 3)
Is the voltage
3.3 V?
Q Q
3 6 7 1 3 1 5
Yes
IC701 (Pin 2)
Is the voltage
1.2 V?
Yes
To Step 3
co
.
VSX-820-K
7
8
9 4 2 8
HDMI 3.3V
No
Check the parts and patterns in
the path.
HDMI 1.8V
No No
Is IC704
abnormally
hot?
Yes
The output and GND may be short-circuited.
Check the path between them.
HDMI 3.3V
No
Check the parts and patterns in
the path.
0 5 8 2 9 9 4 2 8
HDMI 1.2V
No No
Is IC701
abnormally
hot?
Yes
The output and GND may be short-circuited.
Check the path between them.
m
8
9 9
A
B
Replace
IC704.
C
9 9
Replace
IC701.
D
E
F
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