LG 50PS3000 No Voltage

[Easky15]

Got this 50 inch LG plasma TV in, When power lead is connected the tv goes into standby with red LED, When i turn the set on the LED changes to blue and it clicks but i get no display or light from the screen, Tested with a multi meter and im getting 0 volts on both Va and Vs.... Is this a common fault with this tv?

[Alastair E]

Re: LG 50PS3000 No Voltage

Common fault on All Plasma sets!

Check for shorts on Vs lines to both Y-SUS and X-SUS.

[Easky15]

Re: LG 50PS3000 No Voltage

Here's a few pics of the power board, I'm not really sure where to check first, Could you suggest where to start..

https://lh5.googleusercontent.com/-b...225_113946.jpg

https://lh6.googleusercontent.com/-w...225_113936.jpg

https://lh4.googleusercontent.com/-5...225_113906.jpg

[tom66]

Re: LG 50PS3000 No Voltage

Have you tried isolating the Y-sus and Z-sus? Shorted Z-sus is very common on these, usually the TV will buzz loudly when you try to turn it on followed by relays will clicking off.

[Easky15]

Re: LG 50PS3000 No Voltage

Yeah Tom, I already tried disconnecting all boards from power board one at a time and always got the same thing accept for when I removed the main board I got nothing then.

[MagicSmoke]

Re: LG 50PS3000 No Voltage

If it still blows fuse when Y and Z boards are disconnected then fault is on PSU. It can be a bad diode, a shorted Fet, or a number of other things.

[Easky15]

Re: LG 50PS3000 No Voltage

Its not blowing fuses, just no va or vs voltage when set is on, led change from red to blue as if tv is on,

[MagicSmoke]

Re: LG 50PS3000 No Voltage

Some PSU's will shut down VS and VA if there is no load on it. Are any other voltages different or present when tv is on compared to off?

You should be able to jumper 5v Stby to PS-on with a resistor to force PSU on to check other voltage readings. There may also be a VS on pin or the like to activate the VS and VA volts.

Cannot see pin legend on bottom right connector in your pics. Too fuzzy.