Sony KDL-40NX725 Service Manual ▷ View online
KDL-40NX725 28
SECTION 4 - TROUBLESHOOTING
PROTECTION SHUTDOWN
Self Diagnosis
Supported model
Critical voltages and circuit operations are monitored by the CPU
on the Main Board. If a fault is detected the Self-Diagnostic function
in the TV will force the TV to shut down by the CPU. The monitored
circuit in which the fault occurred will cause the CPU to flash the
standby LED in groups of repeating sequences. The number of
blinks in these groups identifies which voltage or circuit caused the
protection event.
Not all of the available protect codes are used in every model.
Not all of the available protect codes are used in every model.
For example, models that are LED backlit do not use the 4-blink
balancer error as this circuit is found in models that are backlight
with fluorescent lamps. The 4-blink error is however, used to identify
an issue with the LD Board for models that contain a LD Board.
The information in this section contains the protect circuits and
diagnostics codes used in the models listed in this manual.
“Figure
4-3. Diagnostic Table” on page 30
provides guidance in locating
the possible component causing the shutdown.
STANDBY LED FLASH COUNT
Ambient Sensor/
(IR) Infrared Receiver
Picture Off /
Timer LED
Standby LED
Power LED
FIGURE 4-1. LED DISPLAY
2 times
5 times
LED ON 0.3 sec.
LED OFF 0.3 sec.
LED OFF 0.3 sec.
LED OFF
3 sec.
FIGURE 4-2. BLINK COUNT
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SECTION 4 - TROUBLESHOOTING
2X Blink - Main Power Error
A loss of REG12V from the power supply triggers this protect event.
A loss of REG12V from the power supply triggers this protect event.
The usual cause is a failure of the main switching supply. In some
instances, excessive loading on the secondary supply lines can
cause the switching regulator to stop, or fail again, if a replacement
board is installed.
3X Blink- DC Regulator/Audio Error
The Audio error can occur due on of the following error conditions.
3X Blink- DC Regulator/Audio Error
The Audio error can occur due on of the following error conditions.
● Defective DC Regulator on Main Board
● Defective Audio Amplifier (Main Board)
● Loss of AU12V (Open F4200 on Main Board)
● Loss of AU12V (Open Fuse on Power Supply Board)
In most cases, replacement of the main board will remedy a 3X error.
4X Blink – Balancer Error
The 4X error code is only used on models incorporating local
4X Blink – Balancer Error
The 4X error code is only used on models incorporating local
dimming LED backlighting. If a failure occurs on the LD board or one
of the LED’s fails in the panel the TV will shut down and display this
diagnostic code. Models using conventional non-local dimming LED
backlighting do not utilize this error code.
5X Blink - TCON Error
The 5X blink protection mode indicates a communications error
5X Blink - TCON Error
The 5X blink protection mode indicates a communications error
between the TCON Board and the X-Reality microprocessor on the
Main Board. If the TCON is available for replacement, replace the
TCON. If the TCON is not available, the LCD panel must be replaced
since the TCON circuit is part of the LCD panel assembly. In rare
cases a loose or defective LVDS cable could also be the cause.
6X Blink - Converter System Failure
If the converter circuit (located on the power supply board) fails to
If the converter circuit (located on the power supply board) fails to
start or shuts down due to an over-voltage or over-current condition,
the unit will shut down and generate a 6X error code. The diagnostic
page labels this as a “Backlight Failure” even though the backlights
are not a source of the problem.
7X Blink – Temperature Error
If the temperature inside the television becomes excessive, the
7X Blink – Temperature Error
If the temperature inside the television becomes excessive, the
temperature sensor (located on the BATL board) notifies the unit
to shut down and display a 7X error. Excessive temperature errors
will always occur when the unit has been running a while and can
be caused by excessive ambient heat or improper ventilation of the
television.
If the television shuts down immediately, this can be caused by a
If the television shuts down immediately, this can be caused by a
defective temperature sensing IC or failure of the communications
bus between the IC and the microprocessor. Replacement of the
main board is necessary.
10X Blink – IR Sync Transmitter Failure
A failure of the infrared sync transmitter circuits on the HEM2 board
10X Blink – IR Sync Transmitter Failure
A failure of the infrared sync transmitter circuits on the HEM2 board
will cause a 10X error and replacement of this board will usually
rectify the problem. In rare cases, the main board could be the
source of the failure.
KDL-40NX725 30
SECTION 4 - TROUBLESHOOTING
DIAGNOSTIC CODE DESCRIPTIONS
The Diagnostic Table provides an overview of the number of times the standby LED blinks and the possible location.
Diagnostic Item
Diagnostic Item
Description
Number of times
Standby LED blinks
Probable Location
MAIN_POWER
Main Power Error
2
G4 Board
DC_ALERT
DC Regulator/Audio Error
AUD_PROT
Audio Error Detection
BALANCER
Balancer Error
4
LCD Panel
LD Board
TCON ERR
TCON Error
P_ID_ERR
Panel ID NVM Error
BACKLITE
Backlight Error
6
G4 Board
TEMP_ERR
Temperature Error
7
Ventilation
BATL Board
EMITTER
Emitter Error
10
HEM2 Board
3
BATL Board
5
TCON Control MT Board
FIGURE 4-3. DIAGNOSTIC TABLE
NOTE: To provide information to customers regarding how to use their TV features or FAQs, refer the customer to the iManual on their TV.
KDL-40NX725 31
SECTION 4 - TROUBLESHOOTING
VIEWING THE SELF CHECK DIAGNOSTIC HISTORY
It is possible to bring up past occurrences of a failure for confirmation
on the Self Check diagnostic history screen. This feature is useful for
failures which are intermittent or when the customer is not sure what
is causing the television to shut down.
1. TV must be in standby mode. (Power off).
2. Press the following buttons on the Remote Commander
within a second of each other:
3.
DISPLAY
Channel
5
Volume
-
POWER
.
* NOTE: This differs from accessing Service Adjustments Mode
(Volume +)
Total operation time by hour (MAX:65535)
Boot count (MAX:65535)
Panel operation time by hour (MAX:65535)
Total operation time by hour (MAX:65535)
Boot count (MAX:65535)
Panel operation time by hour (MAX:65535)
-------------- -------------- -------------- 01
-------------- -------------- -------------- 00
-------------- -------------- -------------- 00
-------------- -------------- -------------- 00
-------------- -------------- -------------- 00
-------------- -------------- -------------- 00
002 MAIN_POWE
003 DC_ALERT
003 AUD_PROT
004 BALANCER
005 HFR_ERR
005 P_ID_ERR
12345-00333-06789
12345
-
00333
-
06789
-
-
-------------- -------------- -------------- 00
006 VLED
-------------- -------------- -------------- 00
005 TCON_ERR
-------------- -------------- -------------- 00
-------------- -------------- -------------- 00
-------------- -------------- -------------- 00
-------------- -------------- -------------- 00
006 BACKLITE
007 TEMP_ERR
010 EMITTER
-------------- -------------- -------------- 00
007 FAN_ERR
-------------- -------------- -------------- 00
012 IA
-------------- -------------- -------------- 00
SELF CHECK
StandBy LED Flash Count
Diagnostic Item
Diagnostic Item
Error Count
(00-99)
-------------- -------------- -------------- 00
-------------- -------------- -------------- 00
101 VPC_WDT
-------------- -------------- -------------- 00
102 MEPS_WDT
-------------- -------------- -------------- 00
103 HOST_WDT
-------------- -------------- -------------- 00
104 STBY_WDT
-------------- -------------- -------------- 00
000 RGB_SEN
000 RESERVED
000 RESERVED
FIGURE 4-4. SAMPLE SELF CHECK DIAGNOSIS PAGE
CLEARING THE SELF CHECK DIAGNOSTIC LIST
Since the diagnostic results displayed on the screen are not
automatically cleared, always check the self-diagnostic screen after
you have completed the repairs to be sure you have cleared the
result display to “0”.
1. To clear the Error history and Error count
press
8
0
.
RESETTING THE LCD PANEL OPERATING HOURS
The 3 sets of numbers displayed on the lower left corner of the screen
indicates the total accumulated operating hours of the television and
the operating hours of the LCD panel. Total operating hours is on the
left, boot count in the center and panel hours in the right group (The
center numbers are not used.)
1. To clear the LCD Panel operating hours of the LCD
Panel after replacing the panel, press
7
0
.
EXITING THE SELF CHECK DIAGNOSTIC SCREEN
1. To exit the Self TCON tconDiagnostic screen, turn off
the power to the TV by pressing the
POWER
button on
the remote or the
POWER
button on the TV.
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