KV-25FS12 - Sony TV Service Manual (repair manual). Page 6

*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.

 

+B Overcurrent 

 

2 times

 

V-STOP   

 

4 times

 

IK (AKB)   

 

5 times

 

*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.

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. If the screen displays a “0”, and error has occurred.

Power does not turn on 

+B overcurrent (OCP)* 

I-Prot

IK (AKB)

Does not light

2 times

4 times

5 times

2:0 or 2:1

4:0 or 4:1

5:0 or 5:1

• Power cord is not plugged in.
• Fuse is burned out (F601). (A Board)

• H.OUT (Q502) is shorted.(A Board)
• IC702 is shorted. (CB Board)

• +13V is not supplied. (A Board)
• IC502 is faulty. (A Board)

• Viedo OUT (IC502) is faulty. (A Board)
• IC1301 is faulty.  (MB Board)
• Screen (G2) is improperly adjusted.**

• 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.