LG 50PK590 WILL TURN ON BUT NO SOUND NO PIC

[samisat]

Hi guys I got this plasma in which when you press the power button ,will comes up but only got back light,no sound ,no picture.I checked power supply and there is not any O/C components.any help Please?
Thanks for your time.
sami

[downunder]

Hi sami,

Might be a good idea to run the Auto Gen on the control board, test points R51, R52, and set if test patterns are displayed.

Bruce

[samisat]

Thanks mate unfortunately I haven't got GAN however i got faulty lamp in screen as going to light up,  then goes off.
  http://www.tv.quuq.org/forum/Smileys/default/c017.gif

[downunder]

GAN? what's that, geeks and nerds?

Auto Gen is an inbuilt pattern generator, activated by disconnecting Control board from Main, shorting out the test holes at R51/R52 on the control board, then switching the tv on. If PSU and scan circuits are working, patterns are generated on the screen. Conclusion - main board is faulty.

And you haven't got a faulty lamp in the screen - it's a plasma tv - they don't have lamps.

Bruce

[Turnip]

Hi folks,
Have one in where it works normally for several days then cuts to S/by Red Led glowing and won't turn on again 'till the next day maybe where it works for some while then cuts again, but it doesn't noticeably click (Favourite issue)

Found some stuff -

For various no go faults R927 & R929(20R 5W)
IC301(3BR1565JF   6 pin chopper) & D304(SR104)
IC701(F4316MSF17   28 pin chip) 
R103  R104(both 240k)  R105  R106(both 150k)  R107(100k) – One series string
R108  R109  R110  R111(all 680k)  R112(620k)  R113(560k) – Other series string, all SMD.

Resistor strings OK - (Checked every one with one end disconnected)  Tend to suspect IC301 though it hasn't popped D304.

Wonder if anyone has thoughts about a 'non click' situation - Thanks - Chris.

[downunder]

Hi Chris,

IC701 has been known to cause int power problem. May be a place to start.                     Bruce

[Turnip]

Thanks Bruce, have one on order,

Just curious a folks always say the set clicks but mine doesn't.

Another chap mentioned that those resistor strings are dubious although maybe read ok - Also that the glue securing the SMD resistors can become suspect - Met that before, mostly on early Sammies - Guess change the lot - Chris.

[CleoHel]

Thanks Bruce, have one of the best rangefinder binoculars ever on order,

Just curious a folks always say the set clicks but mine doesn't.

Another chap mentioned that those resistor strings are dubious although maybe read ok - Also that the glue securing the SMD resistors can become suspect - Met that before, mostly on early Sammies - Guess change the lot - Chris.

Same TV, same problem. My head is spinning from this right now. Please update this thread if you make any progress, Samisat. I'll do the same. Cheers for all the troubleshooting, folks!

[Turnip]

Hi Cleohel,

In my case replacing the resistor strings and a couple of chips and a diode as mentioned - Did the job - Well, it hasn't been back yet, but never can tell - Chris.

PS - Guess you've checked those two big 22R though they were OK on mine.