LG plasma 60PK250N no go

[PowerAmpFreak]

Hi all.
This plasma LG 60PK250N acts strange.
PSU operates correct giving exact voltages both low and high voltages.
Y and X main no drive at all. All cold heatsinks. Power components measures OK.
No LED activity on logic board. It should flash in one Hz or so.
Don't know what it detects.
Tried to activate testmode, shorting the testpads on logic, no LVDS, but it won't activate.
Tried another logic and another mainboard, no difference.
What do you say guys?

[tw2005]

Re: LG plasma 60PK250N no go

Pot shot guess but what happens with the logic isolated from the x or y boards? I don't know the layout .

[PowerAmpFreak]

Re: LG plasma 60PK250N no go

Nothing happens when disconnecting the ribbons between X / Y and logic.

[tw2005]

Re: LG plasma 60PK250N no go

disconnect power from x and y or check if M5V is shorted which is supplied to x, y and the logic. Since the logic is totally dead by 2 maybe 5v missing. Got any training guides?

[PowerAmpFreak]

Re: LG plasma 60PK250N no go

All powersupply lines are OK from PSU. (as told in post #1)
Logic board gets proper power, get warm, local regulator +3,3V and +1,8V giving voltages within spec.
The logic isn't dead, the led is not flashing.

[tw2005]

Re: LG plasma 60PK250N no go

All powersupply lines are OK from PSU. (as told in post #1)
Logic board gets proper power, get warm, local regulator +3,3V and +1,8V giving voltages within spec.
The logic isn't dead, the led is not flashing.

no worries, then i don't know.

if you don't have it, the 60pk750 training guide could be handy.

[PowerAmpFreak]

Re: LG plasma 60PK250N no go

Will check that. Thanks!
If memory serves me right, the flashing led on the logic means it recieve LVDS from mainboard.
But then it would be possible to start the testmode since it's not in need of LVDS.

[tw2005]

Re: LG plasma 60PK250N no go

I wonder what ctrl_en does , runs from ysus to ctrl board. and ctrl_on from zsus. they give levels when running 0.09v & 0.48V

[PowerAmpFreak]

Re: LG plasma 60PK250N no go

It appeard I actually had two BAD ctrl boards.
Found a third one, and set works!
Thanks TW for your assistance!

[tw2005]

Re: LG plasma 60PK250N no go

It appeard I actually had two BAD ctrl boards.
Found a third one, and set works!
Thanks TW for your assistance!

must fix a lot of tvs just to have 2 ,60" logic boards laying around.

[PowerAmpFreak]

Re: LG plasma 60PK250N no go

The other boards were actually for 50" sets. They are not perfect match and picture have timing issues. But still enough to verify.

[tw2005]

Re: LG plasma 60PK250N no go

The other boards were actually for 50" sets. They are not perfect match and picture have timing issues. But still enough to verify.

had a feeling you did something sneeky like that