Samsung PN58C7000 wont power up

[noahc72]

Re: Samsung PN58C7000 wont power up

This is the chart I am talking about. Just trying to go back through and check everything again.

[noahc72]

Re: Samsung PN58C7000 wont power up

Ok, so new main board - tv powers on (doesn't cycle like earlier) but no picture and won't turn off. Checked ps_on and it's really low like 0.1 or so. My earlier post about this was wrong. I had the standyby pin, not ps_on.

Logic board??

[noahc72]

Re: Samsung PN58C7000 wont power up

Do you have to set the new board up in the service menu - panel size/ make

Missed this earlier. Does his need to be done? How do you get to the service menu?

[noahc72]

Re: Samsung PN58C7000 wont power up

Unless I'm measuring wrong, Vs and Va at the connections to x and y boards are way off. I put my meter on 200v dc. Is that the right setting? The readings are off by at least a factor of 10.

I also noticed that since it will now go into standby (led on) after you plug it in that PS_ON is 3.25 in standby and goes to 0.12 after its switched on.

Anyone know what this means?

[tom66]

Re: Samsung PN58C7000 wont power up

Unless I'm measuring wrong, Vs and Va at the connections to x and y boards are way off. I put my meter on 200v dc. Is that the right setting? The readings are off by at least a factor of 10.

I also noticed that since it will now go into standby (led on) after you plug it in that PS_ON is 3.25 in standby and goes to 0.12 after its switched on.

Anyone know what this means?

Maybe your multimeter battery is low - check a new unused AA battery, should measure about 1.6V.

[noahc72]

Re: Samsung PN58C7000 wont power up

Battery looks ok

[tom66]

Re: Samsung PN58C7000 wont power up

Battery looks ok

Unplug both Y and Z and retest.

[noahc72]

Re: Samsung PN58C7000 wont power up

Same reading either way - with meter on 200Vdc, Va is ~1.6 and Vs ~12.0

[tom66]

Re: Samsung PN58C7000 wont power up

Same reading either way - with meter on 200Vdc, Va is ~1.6 and Vs ~12.0

Hmm, way too low. Probably a problem with the PSU then - not sure what though. What is the VSON voltage?

[noahc72]

Re: Samsung PN58C7000 wont power up

Nothing on VSON.

I have 2 power boards. The original and one supposedly pulled from a new/screen damaged tv. All the readings are the same or close on both. Can the logic board cause this? It seems like it could if I'm reading that troubleshooting chart correctly. Otherwise I somehow got another defunct power board.

[tom66]

Re: Samsung PN58C7000 wont power up

Nothing on VSON.

I have 2 power boards. The original and one supposedly pulled from a new/screen damaged tv. All the readings are the same or close on both. Can the logic board cause this? It seems like it could if I'm reading that troubleshooting chart correctly. Otherwise I somehow got another defunct power board.

VSON is probably the problem - needs to be high to send a signal to turn the panel on - usually comes from control board did you replace this?

[noahc72]

Re: Samsung PN58C7000 wont power up

Control board = main or logic board? I did replace the main board.

VSON is from power to logic right? That's the only place I see it.

[tom66]

Re: Samsung PN58C7000 wont power up

Control board = main or logic board? I did replace the main board.

VSON is from power to logic right? That's the only place I see it.

Logic board is the board next to the main board - controls Y and Z sus - from what I remember on the one Samsung plasma I repaired (same "C" series PDP but only 42") it was the board which gave the VSON voltage to turn everything on. However, it's unlikely that it's turning it off for no reason (unlikely to go faulty) - check power is good to the board, check the fuse on it (usually one on Samsung boards), check for loose connectors/cold joints etc. Do you still have the original board to compare with the board that makes the chime?

[noahc72]

Re: Samsung PN58C7000 wont power up

When you asked if I replaced the control board were you talking about the main board or logic board?

Right now I have 2 power boards and 2 main boards. I have tried all possible combos and the results are the same. I also have a replacement logic board on the way.

[noahc72]

Re: Samsung PN58C7000 wont power up

I don't see any fuses on the main boards. Also I mentioned before that the ps_on doesn't look right - 3.25 in standby and 0.12 on. Same with both main boards.

[tom66]

Re: Samsung PN58C7000 wont power up

I don't see any fuses on the main boards. Also I mentioned before that the ps_on doesn't look right - 3.25 in standby and 0.12 on. Same with both main boards.

3.25V is fine for PSON, and sometimes it's active low - must go low to turn PSU on. Don't ask me why, seems strange, but that's how they do it. If you have good 18V etc then main PSU is working, but if VSON is missing then something is up with whatever creates it. These fuses are tiny can you post a pic of your logic board? so I can point out any that may be there.

[noahc72]

Re: Samsung PN58C7000 wont power up

Ok, guess I misunderstood PSON. I thought it was supposed to stay at 3+.

[noahc72]

Re: Samsung PN58C7000 wont power up

pic attached

[selldoor]

Re: Samsung PN58C7000 wont power up

I don't see any fuses on the main boards. Also I mentioned before that the ps_on doesn't look right - 3.25 in standby and 0.12 on. Same with both main boards.

Have you tested ANY fuses if so which.

Thread is getting too long have you posted good clear pictures of the fronts
and backs of all your boards.
Post pics of All the connectors on the power supply other than the one we have.

[tom66]

Re: Samsung PN58C7000 wont power up

There's a fuse on that board with F5A on it and the board has a fuse marker next to it (in the triangle.)

LEDs on control board, do they light up?