Hello
It is due to the self fault diagnosis function built in with every latest Sony sets. According to the faults, and section, number of blinks will deffer in numbers. In your set, two blinks indicates that there is some short circuit occured due to some component faults inside the circuit board of your TV. This fault is calle [OCP], Over Current Protection.
It may be sometimes due to the fault of shorted LOT [Line Output Transformer], or its driver transistor has a short between its collector to emitter leads, or any capacitor shortage, or any kind of short, which causes heavy current flow from the regulated power supply section of your TV.
You just start with the horizontal output transistor stated above. It can be located very near to the LOT. usually screwed onto a metal plate, to radiate heat from it while it works. You just resolder it out from the board and check with multimeter, preferably an analogue one, and measure its collector to emitter resistance, both forward and in reverse mode. If it has a short you will get almost full deflection in the multimter movement. If it is so, you have to suspect the LOT said above too, because horizontal output transistor failure indicates some LOT trouble also.
If so just replace the transistor with same type and number, and switch on the tv just for a short period, say 3 or 4 seconds, and feel the temperature of the replaced transistor with your bare hand, after switch-off the set by unpluging from AC mains outlet. If it overheats, there is some overload, and it is mainly due to the above said LOT. There is an other chance too for this fault. That is deflection yokes' winding short. It is very rare, 1/1000 may occur. Normally an LOT short is found in most cases. If the transitor overheats as said earler, replace the LOT also.
Without the transitor, you just connect a filament bulb of 220v 100W or so, between the main positve rail of the DC supply voltage 130vDC. If the bulb glows constantly, you can make sure that the short is due to lot fault.
An other posibility is shorted secondary filter capacitor and retifier diode. The 130VDC is derived from the secondary side of the SMPS transformer at the power regulator section. There is a rectifier diode and an electrolytic fulter capacitor, normally come to the value of 220MFD 160V or so. If the capacitor gets shorted, it will give a heavy load as stated earlier. Check these components also. OK.
We ran a typical Apple Macbook Pro 17 battery of tests, including games, applications, and a couple other areas. Time constraints limited the amount of testing we could get done before the NDA lift (and it's already a few hours late), but we will be providing a follow-up article with further testing and information. That said, if there are any specific areas that you'd like to see tested, feel free to e-mail me or leave a comment.
Sir
Most of the Sony sets I've got for reapir for the last 37 years of my service, this type of fault I detected a few, occured in the horizontal section itself. I haven't seen no other section related to this fault. Standby light blinks two times, stops and repeat an other two and so on, is very rare case in Sony sets I've came across. Anyway you are doing the most advanced techeneque in testing field, what can I adivce you. Check the entire horizontal section, from oscillator to output. Sometimes the fault may be due to any tiny component like a disc ceramic capacitor or so in that section. But I'm sure that the fault is in the horizontal section itself. I've no other comments.
Gopakuamar.
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