Samsung PN58C7000 wont power up

[noahc72]

2010 Samsung plasma shut itself off the other day and won't turn back on. Red light flashes a few times, then stops, makes a click and repeats. Searching the internet I thought for sure it was the Samsung capacitor issue, but I took the TV apart and looked at all of the capacitors and they all looked fine. Rather than having to replace them until I found the right one I just ordered a whole new power board. Just installed it and no luck - same problem. Any thoughts on what it could be?

Thanks

[tom66]

Re: Samsung PN58C7000 wont power up

Can you take a picture of the inside of your TV? This sounds like a shorted Y-sustain, Z-sustain or Y-buffer.

[noahc72]

Re: Samsung PN58C7000 wont power up

It's a large TV, anything specific I need to zoom in on?

Thanks for the reply

[tom66]

Re: Samsung PN58C7000 wont power up

An overall shot would be good - we need to know the general layout of the boards.

[noahc72]

Re: Samsung PN58C7000 wont power up

pic attached

[tom66]

Re: Samsung PN58C7000 wont power up

Okay, from your picture, the lefthand big board is the Y-Sustain (Y-Main in Samsung terminology) and the right is the Z-Sustain (X-Main.) These connect to the plasma panel and provide the drive waveforms to make it light up and display a picture.

Disconnect the main connector from the power board to the Y-sustain. Do this while the unit is unplugged and has been left for at least 1 minute.

Then attempt to power up the unit. You won't get a picture, but does the power LED behaviour change?

IF it did not change, unplug it and leave for one minute. Then connect the Z-sustain. Check again if the LED does something different.

If it powers up with one of the boards removed, that is the faulty board.

With the Y-sustain the fault can also be caused by the Y-buffer board, but first do these checks, then the buffers can be tested.

[noahc72]

Re: Samsung PN58C7000 wont power up

Tried with y disconnected, no change. Tried with z disconnected, no change.

The click is coming from the power board if that matters.

[tom66]

Re: Samsung PN58C7000 wont power up

Do you have a multimeter?

[noahc72]

Re: Samsung PN58C7000 wont power up

Yes

[tom66]

Re: Samsung PN58C7000 wont power up

Okay, please take a detailed, close picture of the connector going from the power supply to the main board (the board with the inputs on it.)

[noahc72]

Re: Samsung PN58C7000 wont power up

Which one is the main board, y?

[noahc72]

Re: Samsung PN58C7000 wont power up

Oh I get it. Sorry

[noahc72]

Re: Samsung PN58C7000 wont power up

this?

[tom66]

Re: Samsung PN58C7000 wont power up

It looks like it has some labels next to it. One pin is labelled "PS ON". If possible, can you check this pin?

[noahc72]

Re: Samsung PN58C7000 wont power up

I dont see one with ps on, there is sw power.

Also I don't have too much experience with this, what is the correct way to check the pin?

[noahc72]

Re: Samsung PN58C7000 wont power up

Ok I see ps on on the power board. Looks like it goes to sw power on the main board. Not sure how to test it though.

[tom66]

Re: Samsung PN58C7000 wont power up

Ok I see ps on on the power board. Looks like it goes to sw power on the main board. Not sure how to test it though.

Sorry, I wasn't clear - check it with your meter set to 20 VDC. When you go to turn TV on (out of standby) it should rise to around 3 or 5 VDC and stay there.

[noahc72]

Re: Samsung PN58C7000 wont power up

Do I take that connector off and then test the pin?

Also I should have posted - there is no turning it on. Its stuck in this loop so the only thing i can do is plug it in or unplug it. Once you plug it in it will start again and the only way to stop it is unplug it.

[selldoor]

Re: Samsung PN58C7000 wont power up

Leave the connector on - you should be able to get the red lead into the connector.
If you cant, but you can get it onto the swpower pin use that.
- black lead on ground screw just below the socket.
Let it run through its cycle and report what voltages show as the various stages.
In your first post you say the led blinks - How many times -is it always the same- may be an error code.

[noahc72]

Re: Samsung PN58C7000 wont power up

I guess I should have been more precise. The led blinks 6 times, then stops, there is a click from the power board, few second pause, then click again and so on. The led stays off after the 6 blinks.

Tested the ps on - stays at zero then goes to 1.2-1.4 when the click happens and drops back to zero. Does this mean a problem with power?