42PC3D No Prime

[mmartell]

I swore off these sets but here we are...

Set wouldn't turn on until I disconnected the zsus. Powers on and stays on, can hear the static from the speakers on what must be Antenna input but there is no screen prime at all.

I have VS, VA, Vsc but no -Vy. Have not removed the ysus to check components yet. Could shorted buffers pull down just -Vy ?

Also the zsus has no blown fuses so why would it need to have the power harness disconnected for the tv to start ?

And is it safe to run the panel with the x buffers disconnected ?

[mmartell]

Re: 42PC3D No Prime

At some point the zsus fulfilled its destiny as vs is now shorted to ground on it. I'm going to pull the ysus to see if I can find why -Vy is missing. Is -Vy generated straight from Vs on the little sub board ?

I also took some measurements from the dc-dc converter and they don't look right. There are three what I thought were voltage regulators there but the measurements are off unless I'm doing it wrong. Are they not measured at pin 3 with respect to ground ?

[mmartell]

Re: 42PC3D No Prime

Should there be a blinking led on this control board ? I have three temp leds but there is another one at D11 (in a different board location) which never lights.

Also -Vy is missing with buffers both connected and disconnected. If I remove the ribbon going to the control board it comes back rock solid at -200v.

Does this sound like a control board issue ?

[ReeceyBurger123]

Re: 42PC3D No Prime

Yes Led should blink common issue on these is the Ipm under Zmain failing.

[mmartell]

Re: 42PC3D No Prime

This happens with zsus removed. Thanks for the heads up on the blinking light, will order a control board.

[mmartell]

Re: 42PC3D No Prime

This one ended badly. The folding table it was on had a leg give out resulting in the screen cracking itself on the concrete floor. Off to plasma heaven lol.