Troubleshooting - Sony STR-DN1080 Service Manual

Flow of repair (when sound is not outputted)
START
NG
The "PROTECTOR" Check that FFCs between
is not displayed on MB-1613 board and MAIN
the display panel. board are connected certainly.
OK Check completed
The voltage of the following
pin is 2.8 V.
MB-1613 board: IC3002
pin 74 (FUSE_DET)
The voltage of the following
pins are less than 2.13 V.
MB-1613 board: IC3002
pin 95 (TEMP_SENSOR2)
pin 96 (TEMP_SENSOR1)
pin 97 (TEMP_SENSOR3)
The voltage of the following
pin is 3.3 V.
MB-1613 board: IC3002
pin 76 (PROTECTOR)
Check that the defet is
improved, even if you do the
following works.
1. Short-circuit the both ends
2. Perform the "Shipment
Not improved
Replace the MB-1613 board.
A
– Continued the
page 46 –
SECTION 5

TROUBLESHOOTING

NG
OK
NG
OK
NG The following fuses are not
OK
of the C3015 on the
MB-1613 board.
Mode" (refer to page 32)
Check the surrounding circuit
of +7V regulator (IC1351 on the
MAIN board), and replace the
defective parts.
Check the surrounding circuit
of thermistors (TH1251 to
TH1253 on the MAIN board),
and replace the defective parts.
Work completed
damaged.
MAIN board: F910, F911
STANDBY board: F901
OK
Check that the power transistor
(Q1550, Q1551, Q1600, Q1601,
Q1650, Q1651, Q1700, Q1701,
Q1750, Q1751, Q1800, Q1801,
Q1850, Q1851 on the MAIN
board), the power amplifier
(Q1570, Q1620, Q1670, Q1720,
Q1770, Q1820, Q1870 on the
MAIN board) and the
surrounding circuit are not
defect.
OK
Check that the surrounding
circuit of current detect
(Q1554, Q1555, Q1604, Q1605,
Q1654, Q1655, Q1704, Q1705,
Q1754, Q1755, Q1804, Q1805,
Q1854, Q1855 on the MAIN
board) are not defect.
OK
Check the surrounding circuit
of protector (Q1320, Q1321,
Q1323, Q1324, Q1325 on the
MAIN board) and replace the
defective parts.
STR-DN1080/ZA810ES
NG
Between the +59 V line/–59 V
line and the ground does not
short-circuit.
OK
NG
Check the surrounding circuit
of the power transistor
(Q1550, Q1551, Q1600, Q1601,
Q1650, Q1651, Q1700, Q1701,
Q1750, Q1751, Q1800, Q1801,
Q1850, Q1851 on the MAIN
board) and surrounding circuit
of the power amplifer (Q1570,
Q1620, Q1670, Q1720, Q1770,
Q1820, Q1870 on the MAIN
board), and replace the
defective parts.
NG Check the surrounding circuit,
and replace the defective parts.
NG
Measure the power transistor
(Q1550, Q1551, Q1600, Q1601,
Q1650, Q1651, Q1700, Q1701,
Q1750, Q1751, Q1800, Q1801,
Q1850, Q1851 on the MAIN
board) with a tester, and check
the following things.
1. The circuit does not
short-circuit.
2. The resistance is normal.
OK
B
– Continued the
page 46 –
NG
45
SYS SET