SONY KV-21FS120 - KV-24FS120 - LED BLINKING CODES - DISASSEMBLY

APPLICABLE TO:  SONY 

KV-20FS120 RM-Y194 US SCC- S61K-A,

KV-20FS120 RM-Y194 CND SCC- S59H-A,

KV-21FM120 RM-W151 LATIN NORTH SCC- S60X-A,

KV-21FS120 RM-Y194 LATIN NORTH SCC- S60Y-A,

KV-21FS120 RM-Y194 LATIN SOUTH SCC- S73A-A

KV-21FA310 RM-Y180 LATIN NORTH SCC- S60T-A,

KV-21FA310 RM-Y180 LATIN SOUTH SCC- S60U-A,

KV-24FS120 RM-Y194 US SCC- S61L-A,

KV-24FS120 RM-Y194 CND SCC- S59J-A,

KV-25FS120 RM-Y194 LATIN NORTH SCC- S73B-A

KV-25FS120 RM-Y194 LATIN SOUTH SCC- S73C-A.

• When an error occurs, the STANDBY/TIMER LED will fl ash a set number of times to indicate the possible cause of the problem. If there is more than one error, the LED will identify the first of the problem areas.  Results for all of the following diagnostic items are displayed on screen. No error has occurred if the screen displays a “0”.
• If a +B over current is detected, stoppage of the vertical deflection is detected simultaneously. The symptom that is diagnosed first by the micro controller is displayed on the screen.

Diagnostic Item Flash Count [One fl ash count is not used for self-diagnostic.]

+B Overcurrent  à 2 times

I-Prot  à  4 times

IK (AKB)  à 5 times.

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] à [CHANNEL-5] à [SOUND VOLUME (-Ve)] à [POWER ON].

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] à  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.

+B over current (OCP)

Occurs when an over current 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 defl ection 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.

LED BLINKING CODES [DETAILS]

Diagnostic Item Description	No. of times STANDBY/ TIMER lamp flashes	Self-Diagnostic Display/Diagnostic Result	Probable Cause Location	Detected Symptoms
Power does not turn on	Does not light	----------	• Power cord is not plugged in. • Fuse is burned out (F601). (A Board)	• Power does not come on. • No power is supplied to the TV. • AC Power supply is faulty.
+B over current (OCP)	2 times	2:0 or 2:1	• H.OUT (Q506) is shorted. (A Board) (20”/21” models only) H.OUT (Q505) is shorted. (A Board) (24”/25” models only) • RGB Amp (IC1751) is shorted. (CV Board)	• Power does not come on. • Load on power line is shorted.
I-Prot	4 times	4:0 or 4:1	• +13V is not supplied. (A Board) • IC545 is faulty. (A Board)	• Has entered standby state after horizontal raster. • Vertical defl ection pulse is stopped. • Power line is shorted or power supply is stopped.
IK (AKB)	5 times	5:0 or 5:1	• Video OUT (IC545) is faulty. (A Board) • IC001 is faulty. (A Board) • Screen (G2) is improperly adjusted	• No raster is generated. • CRT Cathode current detection reference pulse output is small.

DISASSEMBLEY

REAR COVER REMOVAL (ALL EXCEPT KV-21FA310)

Remove screws.

REAR COVER REMOVAL (KV-21FA310 ONLY)

Lift to remove Sub-woofer.

Remove screws.

CHASSIS REMOVAL

SERVICE POSITION

• Push down on clips to release K Board, then unplug the 2 pin woofer connector and move out of the way.
• Press on catch tab to release A Board.
• Disconnect remaining cables to allow A Board to be removed.