LG 42PG20 no video

[microvibe]

Have lg 42pg20. When I got it the tv it would just click then turn off. Disconnected zsus and it would turn on and stay on. Replaced 4 blown fets on zsus now when I turn on it stays on but no panel glow or any thing.

I have all correct voltages from psu to ysus but from ysus to zsus I have 188v for vs and 3v for zsus no changes when buffer disconnected. Can't find any shorts on ysus ethier. Not sure what to check on ysus or do I just get new ysus?

[freakaftr8]

Re: LG 42PG20 no video

Are those IPM modules under the heat syncs?

[microvibe]

Re: LG 42PG20 no video

No just gets attached this model doesn't have those ipm

[freakaftr8]

Re: LG 42PG20 no video

Do you have VSCAN on Ysus? And are there two buffer boards or just One?

[microvibe]

Re: LG 42PG20 no video

There is just one buffer board. There is no vscan voltage it's like 3 volt with or without buffer connected.

[freakaftr8]

Re: LG 42PG20 no video

So what you're saying is you are getting VS voltage to YSUS not ZSUS? What is VS voltage per panel label?

[microvibe]

Re: LG 42PG20 no video

Vs going to ysus and vs leaving ysus to zsus at 188v as per panel spec. Va is 59v as per panel spec.

[freakaftr8]

Re: LG 42PG20 no video

Ok. What are you measuring that only has 3v?

[microvibe]

Re: LG 42PG20 no video

The vsc vsy points with and without buffer connected.

[microvibe]

Re: LG 42PG20 no video

Did more testing replaced more shorted fets on zsus.

From connector ysus to zsus I have 188v on vs the 3 zsus labeled pins have 31v. When I put test pattern jumper on control board the zsus pins jump from 31v to 60v still no image on screen. The connection from zsus to control board I get 4.8v on 15v pins and nothing on the sus on or sus dn pins. I tested vsc and vsy on ysus with and without buffer jumps to 28v when control board in test pattern mode.

Any ideas where check

[microvibe]

Re: LG 42PG20 no video

Was thinking I have bad ysus but cant find any shorts .