Troubleshooting - Sony HT-NT3 Service Manual

1. "PRTECT" is displayed on the fl uorescent indicator tube after turning the power on
"PRTECT" is displayed on the
fluorescent indicator tube after
turning the power on.
Yes
"PRTECT" is not displayed, when
Yes
removing the speaker and turning Check and replace the speaker.
the power on.
No
Check that AMP board IC6001
Yes
Exchange AMP board IC6001
pin 27, 28, 32, 35, 39 and 40 is
(6-721-742-01)
short to GND.
No
AMP board damage. Exchange
complete AMP board.
2. The video of HDMI is not displayed normally
No
Check that each power supply is
Refer to the "Power is not turned
supplied. on" on page 27.
Yes
Check that only the digital output No
Check the settings on the menu
(HDMI) is affected.
screen.
Yes
Check that the input voltage of the
No
Refer to the "Power is not turned
following pin is around 7.4V - 8V.
on" on page 27".
MB-1407 board IC5014 pin 5 (VIN).
Yes
Check that the output voltage of the
Check that the input voltage of the
No
following pin is 5V. MB-1407 board
following pin is 3.3V. MB-1407
IC5014 pin 4 (VOUT). board IC5014 pin 1 (CONT).
Yes
Exchange the MB-1407 board IC5014.
Part No. : 6-718-999-01
Description: IC MM1839A50NRE
Exchange the MB-1407 board CN5012.
Note: When CN5012 is exchange, be
Check that there are no
careful of the quality of soldering
No
abnormalities in MB-1407 board
enough.
CN5012.
Part No. : 1-821-398-41
Description: HDMI CONNECTOR
Yes
(HDMI OUT ARC HDCP 2.2)
Perform other analyses.
HT-NT3
SECTION 4

TROUBLESHOOTING

No Refer to the "Power is not turned
on" on page 27".
Yes
3. The sound is not outputted
Yes
The sound is not outputted.
4. Power is not turned on
Power is not turned on.
Yes
Reprogram IF - con.
Yes
The voltage of the following is 20V/32V
SWITCHING REGULATOR (3L405W):
CN101 pin 2 to 4 and 8.
Yes
Check AMP board CN6007 pin 2 is 12V.
Yes
Check pin 1 of CN301 in MB-1407 board.
Yes
Check MB-1407 board IC3004 pin 1
Yes
Check X3001 on the MB-1407 board
whether is oscillating or not after AC IN.
Yes
Check the reset signal of pin 49 of
IC3004 on MB-1407 board during AC IN
or power on (there is a quick low pulse
to indicate reset signal).
Yes
Check PCONT1: pin 119
Check PCONT3: pin 123
Check SPARTA_PCONT: pin 65
Yes
Check each voltage with reference
to the schematic diagram and check
that there is no problem in them.
Yes
Check the related IC on MB-1407 board.
27 27
No Change FFC insert to AMP Board
Check that the signal is input to
CN6004.
AMP board IC6002 pin 24 and 27.
Yes
Check that the PWM signal is
No
outputted from the following pins. Exchange AMP board IC6002
AMP board IC6002 pin 38, 39, 40,
(6-718-105-01)
41, 48 and 49.
Yes
Check that the signal is outputted
No
Exchange AMP board IC6001
from AMP board IC6001
pin 27, 28 and 32 (SP FRONT R) (6-721-742-01)
pin 35, 39 and 40 (SP FRONT L)
No
Replace the SWITCHING
REGULATOR (3L405W).
No
Check IC6003 funtion.
No
No
Check pin 3 of CN703 in MB-1407
Replace MB-1407 board.
board.
Yes
No
Replace MB-1407 board.
No
Replace MB-1407 board.
No
Replace MB-1407 board.
No
Replace MB-1407 board.
No
Power supply IC is damaged.
Exchange the power supply IC.
HT-NT3