Self-Diagnostic Function - Sony TRINITRON KV-20FS120 Service Manual

The units in this manual contain a self-diagnostic function. If an error occurs, the STANDBY/TIMER LED will automatically begin to fl ash. The number
of times the LED fl ashes translates to a probable source of the problem. A defi nition of the STANDBY/TIMER LED fl ash indicators is listed in the
instruction manual for the user's knowledge and reference. If an error symptom cannot be reproduced, the Remote Commander can be used to review
the failure occurrence data stored in memory to reveal past problems and how often these problems occur.
Diagnostic Test Indicators
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 fi rst 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".
No. of times
Diagnostic Item
STANDBY/ TIMER
Description
lamp fl ashes
Power does not turn on Does not light
+B overcurrent (OCP)*
2 times
4 times
I-Prot
5 times
IK (AKB)
*If a +B overcurrent is detected, stoppage of the vertical defl ection is detected simultaneously. The symptom that is diagnosed fi rst by the
mircrocontroller is displayed on the screen.
**Refer to Screen (G2) Adjustments in Section 2-4. of this manual.
Display of Standby/Timer LED Flash Count
2 times
4 times
5 times
LED ON 0.3 sec.
LED OFF 0.3 sec.
Diagnostic Item
+B Overcurrent
I-Prot
IK (AKB)
*One fl ash count is not used for self-diagnostic.
Stopping the Standby/Timer LED Flash
Turn off the power switch on the TV main unit or unplug the power cord from the outlet to stop the STANDBY/TIMER LAMP from fl ashing.
KV-20FS120/21FM120/21FS120/21FA310/24FS120/25FS120

SELF-DIAGNOSTIC FUNCTION

Self-Diagnositc
Probable Cause Location
Display/
Diagnostic Result
• Power cord is not plugged in.
• Fuse is burned out (F601). (A Board)
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)
4:0 or 4:1 • +13V is not supplied. (A Board)
• IC545 is faulty. (A Board)
• Video OUT (IC545) is faulty.
5:0 or 5:1
(A Board)
• IC001 is faulty. (A Board)
• Screen (G2) is improperly adjusted.**
LED OFF
3 sec.
Flash Count*
2 times
4 times
5 times
KV-20FS120/21FM120/21FS120/21FA310/24FS120/25FS120
Self Diagnosis
Supported model
Detected Symptoms
• Power does not come on.
• No power is supplied to the TV.
• AC Power supply is faulty.
• Power does not come on.
• Load on power line is shorted.
• Has entered standby state after horizontal raster.
• Vertical defl ection pulse is stopped.
• Power line is shorted or power supply is stopped.
• No raster is generated.
• CRT Cathode current detection reference pulse
output is small.
Standby/Timer LED
8