Troubleshooting - Sony HT-ST9 Service Manual

1. "PRTCT" is displayed on the OLED display after turning the power on
"PRTCT", "PUSH" and "POWER"
display alternately in the OLED
display after turning the power on.
Yes
IC7004, IC7005, IC7007, IC7008
on the AMP board is burned out.
No
"PRTCT", "PUSH" and "POWER" is
not displayed alternately in the
OLED display, when removing the
speakers (SP1 to SP10) and
turning the power on.
No
The voltage of the following is 3.3 V.
MB1406 board: IC3004 pin 96
(DRIVER_SD)
No
The voltage of the following is 12 V.
AMP board: IC7004, IC7005,
IC7007, IC7008
No
Check and repair the IC7001 and
surrounding circuit on the AMP
board.
SECTION 4

TROUBLESHOOTING

Yes
Replace the IC7004, IC7005,
IC7007, IC7008 on the AMP board.
Check and replace the speakers
Yes
(SP1 to SP10) and connection
cable (SPC1 to SPC4).
Yes
The voltage of the following is 3.3 V.
MB1406 board: IC3004 pin 50
(DC_DET)
OUT_D line (pin 27, 28), OUT_C
line (pin 32), OUT_B line (pin 35)
and OUT_A line (pin 39, 40) of
IC7004, IC7005, IC7007, IC7008
on the AMP board do not
short-circuits or opens.
If there is no abnormality, replace
the IC7004, IC7005, IC7007,
IC7008 on the AMP board.
Mounted parts on the INPUT_D line
Yes
(pin 15), INPUT_C line (pin 14),
INPUT_B line (pin 6) and INPUT_A
pin 2
line (pin 5) of IC7004, IC7005,
IC7007, IC7008 on the AMP board
short-circuits or opens.
The PWM signal is inputted
INPUT_D line (pin 15), INPUT_C
line (pin 14), INPUT_B line (pin 6)
and INPUT_A line (pin 5) of IC7004,
IC7005, IC7007, IC7008 on the
AMP board.
Check and repair the IC7006 and
surrounding circuit on the AMP
board.
– From the page 54 –
No
Yes
Repair the short-circuit and opening
of mount parts.
No
Yes
Replace the IC7004, IC7005,
IC7007, IC7008 on the AMP board.
No
HT-ST9
A
53