Read Sony KV-21FA210 (serv.man2) Service Manual online
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KV-21FA210
Self-Diagnostic Screen Display
For errors with symptoms such as “power sometimes shuts off” or “screen sometimes goes out” that cannot be confirmed, 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:
Display
Channel 5
Sound Volume -
Power ON
Self-Diagnostic Screen Display
Numeral “0” means that no fault was detected.
Numeral “1” means a fault was detected one time only.
SELF DIAGNOSTIC
2: 000
3: N/A
4: 000
5: 001
101: N/A
3: N/A
4: 000
5: 001
101: N/A
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”.
Unless the result display is cleared to “0”, the self-diagnostic function will not be able to detect subsequent faults after completion of the repairs.
Clearing the Result Display
To clear the result display to “0”, press buttons on the Remote Commander sequentially when the diagnostic screen is displayed, as shown below:
Channel 8
ENTER
Quitting the Self-Diagnostic Screen
To quit the entire self-diagnostic screen, turn off the power switch on the Remote Commander or the main unit.
Self-Diagnostic Circuit
+B overcurrent (OCP)
Occurs when an overcurrent on the +B (135V) line is detected by pin 72 of IC001 (A Board). If the voltage of pin 72 of IC001 (A Board) is less than 1V
when V.SYNC is more than seven verticals in a period, the unit will automatically turn off.
I-Prot
Occurs when an absence of the vertical deflection pulse is detected by pin 78 of IC001 (A Board). Power supply will shut down when waveform interval
exceeds 2 seconds.
IK (AKB)
If the RGB levels* do not balance within 2 seconds after the power is turned on, this error will be detected by IC001 (A Board). TV will stay on, but
there will be no picture.
*(Refers to the RGB levels of the AKB detection Ref pulse that detects 1K).
Note that this differs from entering the Service Mode (Sound Volume + ).
A BOARD
IC001
Y/CHROMA JUNGLE
A BOARD
IC545
V. OUT
A BOARD
IC001
SYSTEM
A BOARD
IC002
MEMORY
IK-AKBIN
FROM
CV BOARD
IC1751 PIN 5
I-HLDWN
FROM
A BOARD
IC561
PIN 7
72
O-LED
REF
I-Prot
IO-BDAT
BDA
DISPLAY
51
3
78
79
53
5
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