LG 50PS3000-ZB.BEKLLJP

[daz]

hi guys
this one comes out of standby, you get a blank grey-ish screen for 1 second then it switches to the tv picture which is hazy white with lots of red dots, this lasts another second then the set shuts down.
any ideas??
thanks
daz
forgot to say, fault was intermitent, set would run for some time then the picture would go white.red then shut down

[Ohm Supplies]

Daz,

Have you tried disconnecting the y-sus?
regards
ANdy

[daz]

hi andy
yes unplugging the ysus allows the set to start, as does unplugging one at a time the upper buffer,lower buffer, lvds cable, ribbon con from cntl pcb to ysus.
finaly noticed (getting slow these days) 15v to zsus high at 17v and a short fet on zsus, atempts at repair failed, looks like i need two boards but customer is tight so onto the scap pile it went (for the time being)
thanks

daz

[daz]

Hi all,
ohm supplies now do a kit to fix this fault, which I tried but it didn’t work, suspect my failed attempt to repair the z sus pcb may have caused damage to the control pcb.
this seems to be a common fault on this set, the z sus gets too hot and fails due to the control pcb being faulty. However the TV will run ok for a while before this happens.
If anyone has had this fault before and has swopped the control pcb, do you still have the old pcb you could lend me? It should allow the set to run for a short time so I can do some checks.
Here is a pic
Thanks
Daz

ebr54863601

[Ohm Supplies]

Hello,

the repair kit has been well tested and used by LG service agents for a few months with no problems, the x and control board both need to have the parts fitted to stop over heating, the new fets do run hot for a short time then settle. Fitting a new contol board doesnt seem to work but a used one might be ok (never done it)

regards
Andy

[dougc]

Yes, just used one of Andy's kits & it was spot on & comparitively easy to fit.

[daz]

hi guys
sorry i didnt explain the fault very well, i no longer have the original fault, after fitting a fet which was not upto the job, it failed (with a bang) i fitted the kit i got off andy which contained the fet and all the components that failed the second time, i now have no pic at all, nothing seems to be running, and i have had  a good check around all the pcbs and i can find no faulty components, so i am guessing i blew the control pcb, hence the request for a control pcb to try. i suspect if i had fitted the the kit when i had the original fault it would have fixed the set.  but at the time i did not know a kit was alvailable, you live and learn i guess.
thanks
daz