Sony SA-CT800 - No Sound Output; Power Not Turning On

HT-CT800
HT-CT800
4343
3. The sound is not outputted
Entering the “DEMO MODE” (touch
the [INPUT] button for five seconds),
and then the “DEMO MODE” sound
is outputted.
(Touch the [1] button to release the
“DEMO MODE”)
The sound is not outputted.
No
Yes
Check the signal path for being inputted to
the IC101 on the MB-1612 board, and
then replace the complete MB-1612 board.
(IC101 and digital power amplifier
(IC6005) on the MB-1612 board is OK)
Yes
The voltage of the following is 33 V.
MB-1612 board: IC6005 pin 29 to 31,
36 to 38 (PVDD)
Yes
No
The PWM signal is inputted INPUT
_A (pin 5), INPUT_B (pin 6), INPUT
_C (pin 14) and INPUT_D (pin 15)
lines of IC6005 on the MB-1612
board.
Check the B+ line and signal line of
the IC705 and IC6004 on the MB-
1612 board, and then replace the
complete MB-1612 board.
Check the fuses (F6002, F6003) on the
MB-1612 board and if it damaged, replace
the fuses (F6002, F6003) on the MB-1612
board.
No
Yes
Check the OUT_A (pin 39, 40), OUT_B
(pin 35), OUT_C (pin 32) and OUT_D
(pin 27, 28) lines of IC6005 on the MB-
1612 board do not short-circuits or opens.
If there is no abnormality, replace the
IC6005 on the MB-1612 board.
4. Power is not turned on
Power is not turned on.
The voltage of the following is 33 V.
POWER board: CN904 pin 3 to 5
The voltage of the following is 12 to
18 V.
POWER board: CN904 pin 9
The voltage of the following is 3.3 V.
MB-1612 board: IC5001 pin 1
Yes
POWER board is damaged.
Yes
Yes
Vibrator (X5001) on the MB-1612
board is oscillated after AC input.
Yes
Fuse (F901) on the POWER board
conduct the electricity.
No
No
No
Replace the MB-1612 board.
The reset signal is inputted to pin
49 of IC5001 on the MB-1612 board
after AC input.
Check the area surrounding IC5005 on
the MB-1612 board, and then replace the
MB-1612 board.
Yes
Yes
No
Replace the MB-1612 board.
No
Replace the fuse (F901) on the POWER
board.
No
Replace the MB-1612 board.
The voltage of the following is 3.3 V.
MB-1612 board: C356 (JL326)
MB-1612 board: C364 (JL330)
The voltage of the following is 12 to 18 V.
MB-1612 board: IC306 pin 5
SYSSET
2019/09/2422:06:08(GMT+09:00)