LG 50PS3000 not powering up

[rickysmith482]

Hi All
First post here so be kind to the newbie.
I have an LG 50PS3000 and when I power up the blue light flashes then a bright screen that looks like a colour negative appears for a couple of second then the TV clicks and powers off. I have been told it may be the power supply board shutting down due to a failing ZSUS board. Can anybody confirm and if so tell me how to identify the location of the offending ZSUS board so that I might get the part number and find a replacement.
Thanks in advance.
Ricky

[PlainBill]

Re: LG 50PS3000 not powering up

Hi All
First post here so be kind to the newbie.
I have an LG 50PS3000 and when I power up the blue light flashes then a bright screen that looks like a colour negative appears for a couple of second then the TV clicks and powers off. I have been told it may be the power supply board shutting down due to a failing ZSUS board. Can anybody confirm and if so tell me how to identify the location of the offending ZSUS board so that I might get the part number and find a replacement.
Thanks in advance.
Ricky

The operative word is 'might'. Replacing the Z-sustain because someone said it 'might' be the problem is a little like buying an expensive pair of shoes because someone said they 'might' improve your social life.

The service manual is available at Elektrotanya.

When you remove the back of the TV, the Z-sustain is on the right hand side, the Y-sustain on the left as you face the back of the TV. The standard troubleshooting process is to disconnect the power cables to the Z-sustain and turn the TV on. If it still won't power up the Z-sustain is NOT the problem. Reconnect the Z-sustain and unplug the Y-sustain power cable. Again, try to turn on the TV. If it STILL won't power up, the probable cause is the power supply. Try disconnecting both Y and Z sustains. If it now powers up, the problem is almost certainly the power supply.

PlainBill

[mikehiw]

Re: LG 50PS3000 not powering up

Sorry to drag up an old thread, but I have what sounds like the very same issue.

It started with image retention showing over the main picture as a purple hazy picture. This has been going on for around a month. This morning the TV turned up, showed this purple haze, went white and went back into standby.

Disconnecting power from Zsus or Ysys boards made no odds.

Vs and Va are within spec during the short time before the TV goes back into standby.

I'm no stranger to electronics but I haven't a clue with it comes to TVs - I've checked as much as I can find I should be checking, but now I'm out of ideas. Caps all look clean and flat.

[mikehiw]

Re: LG 50PS3000 not powering up

Just having a better look at this - I was mistaken when I disconnected the Zsus board.

Disconnecting it does indeed keep the TV on. When leaving it connected, there is a loud whine from the zsus board before it switches the whole unit off.

Any suggestions on where I should be looking for a component level repair? If I have to buy expensive boards to repair it, I may as well bin the TV and put the money towards a new one I wanted anyway.

[tw2005]

Re: LG 50PS3000 not powering up

Just having a better look at this - I was mistaken when I disconnected the Zsus board.

Disconnecting it does indeed keep the TV on. When leaving it connected, there is a loud whine from the zsus board before it switches the whole unit off.

Any suggestions on where I should be looking for a component level repair? If I have to buy expensive boards to repair it, I may as well bin the TV and put the money towards a new one I wanted anyway.

Post the board number and some hi res shots. how expensive is too much?

For example there appears to be 3 or 4 types of ZSUS and this one $30 but shipping can be a killer.
http://www.shopjimmy.com/lg-ebr58838...h3a-z-zsus.htm

Shorted out transistors would be where I'd start looking.