Sony STR-DH590, Руководство по обслуживанию

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STR-DH590
33
SECTION 5
TROUBLESHOOTING
Flow of repair (when sound is not outputted)
NG
OK
OK
OK
Work completed
OK OK
Work completed
NG
NG
Check that FFCs between
H59-DIGITAL board and
MAIN board are connected
certainly.
The voltage of the following
pin is 2.8 V.
H59-DIGITAL board: IC3001
pin 86 (FUSE_DETECT)
The voltage of the following
pin is 3.3 V.
H59-DIGITAL board: IC3001
pin 106 (PROTECT)
Check the surrounding circuit
of +7V regulator (IC102 on the
MAIN board), and replace the
defective parts.
The voltage of the following
pins are less than 2.13 V.
H59-DIGITAL board: IC3001
pin 87 (TEMP_SENSOR_1)
pin 88 (TEMP_SENSOR_2)
pin 89 (TEMP_SENSOR_3)
Check the surrounding circuit
of thermistors (TH100 to
TH102 on the MAIN board),
and replace the defective parts.
NG The following fuses are not
damaged.
MAIN board: F102, F103
STANDBY board: F901
START
The “PROTECT”
is not displayed on
the display panel.
A
– Continued the
page 34 –
B
– Continued the
page 34 –
OK
OK
Not improved
OK
OK
NG
NG NG
NG
Between the +59 V line/–59 V
line and the ground does not
short-circuit.
Check that the defet is
improved, even if you do the
following works.
1. Short-circuit the both ends
of the C3074 on the
H59-DIGITAL
board.
2. Perform the “Shipment
Mode” (refer to page 24)
Check that the power transistor
(Q120, Q121, Q130, Q131,
Q140, Q141, Q150, Q151,
Q160, Q161 on the MAIN
board), the power amplifier
(Q126, Q136, Q146, Q156,
Q166 on the MAIN board) and
the surrounding circuit are not
defect.
Check that the surrounding
circuit of current detect
(Q114, Q115, Q124, Q125,
Q134, Q135, Q144, Q145,
Q154, Q155, Q164, Q165,
Q174, Q175 on the MAIN
board) are not defect.
Check the surrounding circuit
of protector (Q101, Q102,
Q103, Q104, Q105 on the
MAIN board) and replace the
defective parts.
Check the surrounding circuit
of the power transistor
(Q120, Q121, Q130, Q131,
Q140, Q141, Q150, Q151,
Q160, Q161 on the MAIN
board) and surrounding circuit
of the power amplifer (Q126,
Q136, Q146, Q156, Q166 on
the MAIN board), and replace
the defective parts.
NG Check the surrounding circuit,
and replace the defective parts.
Replace the H59-DIGITAL
board.
Measure the power transistor
(Q120, Q121, Q130, Q131,
Q140, Q141, Q150, Q151,
Q160, Q161 on the MAIN
board) with a tester, and check
the following things.
1. The circuit does not
short-circuit.
2. The resistance is normal.