Sony KV-BT21M40 Service Manual ▷ View online
– 5 –
KV-BT21M40/BT21P52/BT21P52/L/BT21P52/N
RM-W101
2. DISPLAY OF
STANDBY (1)
INDICATOR
FLASH COUNT
3. STOPPING THE
STANDBY (1)
INDICATOR FLASH
Turn off the power switch on the TV main unit or unplug the power cord from the outlet to stop the STANDBY (1)
indicator from flashing.
indicator from flashing.
4. SELF-DIAGNOSTIC SCREEN DISPLAY
For errors with symptoms such as "power sometimes shuts off" or "screen sometimes goes off" that cannot be confirmed,
it is possible to bring up past occurrences of failure on the screen for confirmation.
it is possible to bring up past occurrences of failure on the screen for confirmation.
[To Bring Up Screen Test]
In standby mode, press buttons on the remote commander sequentially in rapid succession as shown below:
In standby mode, press buttons on the remote commander sequentially in rapid succession as shown below:
Display
/ Channel 5 / Volume
/ Power
/ TV
˘
Note that this differs from entering the service mode (volume [+]).
Note that this differs from entering the service mode (volume [+]).
The following screen will be displayed indicating the error count.
Diagnostic Item
Flash Count*
+B overcurrent
2 times
V-Protect
4 times
IK (AKB)
5 times
Power Supply NG (+5V)
8 times
for Video processor
* One flash count is not used for self-diagnosis.
Lamp ON 0.3 sec.
Lamp OFF 3 sec.
Lamp OFF 0.3 sec.
2 times
4 times
5 times
8 times
2 :
0
3 :
N/A
4 :
0
5 :
1
8 :
0
101 :
N/A
SELF DIAGNOSTIC
Numeral "0" means that no fault was detected.
Numeral "1" means the number of a fault occurrence (1 ~ 255).
Numeral "1" means the number of a fault occurrence (1 ~ 255).
STANDBY (1) indicator
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KV-BT21M40/BT21P52/BT21P52/L/BT21P52/N
RM-W101
A BOARD
IC001
Y/CHROMA JUNGLE
A BOARD
IC001
SYSTEM
A BOARD
IC003
MEMORY
FROM
CV BOARD
IC1751 PIN 5
IK-AKBIN
I/HLDWN
IO-BDAT
V-guard
BDA
DISPLAY
O-LED
A BOARD
IC804
V. OUT
REF
5
84
32
122
A BOARD
FROM
Q816
Collector
99
13
3
5. HANDLING OF SELF-DIAGNOSTIC SCREEN DISPLAY
Since the diagnostic results displayed on the screen are not automatically cleared, always check the self-diagnostic
screen during repairs. When you have completed the repairs, clear the result display to “0”.
screen during repairs. When you have completed the repairs, clear the result display to “0”.
Unless the result display is cleared to “0”, the self-diagnosis function will not be able to detect subsequent faults after
completion of the repairs.
completion of the repairs.
[Clearing the result display]
To clear the result display to “0”, press buttons on the remote commander subsequent as shown below when the
self-diagnostic screen is being displayed.
To clear the result display to “0”, press buttons on the remote commander subsequent as shown below when the
self-diagnostic screen is being displayed.
8
, -
[Quitting Self-diagnostic screen]
To quit the entire self-diagnostic screen, turn off the power switch on the remote commander or the main unit.
To quit the entire self-diagnostic screen, turn off the power switch on the remote commander or the main unit.
6. SELF-DIAGNOSTIC CIRCUIT
[+B overcurrent $OCP%]
Occurs when an overcurrent on the +B(135V) line is detected by pin 32 of IC001 (A board).
If the voltage of pin 32 of IC001 (A board) is more than 4V, the unit will automatically go to
standby.
If the voltage of pin 32 of IC001 (A board) is more than 4V, the unit will automatically go to
standby.
[V-PROTECT]
Occurs when an absence of the vertical deflection pulse is detected by pin 13 of IC001
(A board).
(A board).
[IK $AKB%]
If the RGB levels* do not balance within 15 sec after the power is turned on, this error will be
detected by IC001 (A board). TV will stay on, but there will be 5 times LED blinking.
detected by IC001 (A board). TV will stay on, but there will be 5 times LED blinking.
Occurs when IC001 internal HV protect detects an abnormal H-Pulse (frequency) due to
improper power supply to IC001. TV cuts off high voltage power of anode CRT. No picture
will be detected. eg: IC602, IC604 go faulty.
improper power supply to IC001. TV cuts off high voltage power of anode CRT. No picture
will be detected. eg: IC602, IC604 go faulty.
* (Refers to the RGB levels of the AKB detection Ref pulse that detects IK.)
POWER SUPPLY NG (+5V)
for VIDEO PROCESSOR
for VIDEO PROCESSOR
– 7 –
KV-BT21M40/BT21P52/BT21P52/L/BT21P52/N
RM-W101
SECTION 1
DISASSEMBLY
1-1.
REAR COVER REMOVAL
1-2.
SPEAKER REMOVAL
1-3.
CHASSIS ASSY REMOVAL
1-4.
SERVICE POSITION
1-5.
TERMINAL BRACKET REMOVAL
1-6.
A BOARD REMOVAL
2 Rear cover
1 Eight screws
(+BVTP 4
(+BVTP 4
× 16)
1 Four screws
(Washer Head)
(+P4
(Washer Head)
(+P4
× 16)
2
Terminal bracket
3 Two screws
(+BVTP 4
(+BVTP 4
× 16)
1 One screws
(+BVTP 3
(+BVTP 3
× 12)
A Board
– 8 –
KV-BT21M40/BT21P52/BT21P52/L/BT21P52/N
RM-W101
• REMOVAL OF ANODE-CAP
Note:
• After removing the anode, short circuit the anode of the picture tube and the anode cap to the metal chassis, CRT
shield or carbon paint on the CRT.
• REMOVING PROCEDURES
1
Turn up one side of the rubber cap in the direction
indicated by the arrow A.
indicated by the arrow A.
2
Using a thumb pull up the rubber cap firmly in the di-
rection indicated by the arrow B.
rection indicated by the arrow B.
3
When one side of the rubber cap is separated from
the anode button, the anode-cap can be removed by
the anode button, the anode-cap can be removed by
turning up the rubber cap and pulling it up in the
direction of the arrow C.
direction of the arrow C.
• HOW TO HANDLE AN ANODE-CAP
1
Do not damage the surface of anode-caps with
sharp shaped objects.
sharp shaped objects.
2
Do not press the rubber too hard so as not to
damage the inside of anode-cap.
A metal fitting called the shatter-hook terminal is
built into the rubber.
damage the inside of anode-cap.
A metal fitting called the shatter-hook terminal is
built into the rubber.
3
Do not turn the foot of rubber over too hard.
The shatter-hook terminal will stick out or damage
the rubber.
The shatter-hook terminal will stick out or damage
the rubber.
anode button
a
a
b
b
c
1-7.
PICTURE TUBE REMOVAL
Note:
• Pls make sure the TV set is not in standing position before removing necessary CRT support located on bottom
right and left.
1) Place the TV set with the CRT face down on a cushion jig.
2) Remove the rear cover.
3) Unplug all inter connecting leads from the Deflection Yoke, Degaussing Coil and CRT grounding strap.
2) Remove the rear cover.
3) Unplug all inter connecting leads from the Deflection Yoke, Degaussing Coil and CRT grounding strap.
qs
Earth Coating Assy
9
Holder, DGC(2) Removal
4
Anode Cap Removal
5 C Board Removal
7 Chassis Assy Removal
0
Spring Tension(2) Removal
qd
Nut, Special, CRT (4)
qa
Degaussing Coil
3 Loosen the Neck Assembly
fixing screw and remove
6
Loosen the Deflection Yoke
fixing screw and remove
8 Support, CRT(2) Removal
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