Samsumg Plasma 58" PN58B540 PowerSupply Shutdown

[Tony2706]

Hi All. First Post. I have a Samsung plasma that is shutting itself down. After the shutdown, the set remain powered off with the red standby light on. When cold, the tv takes 10ish minutes to shutdown. If I try to re-turn on the set, the time to shutdown gets shorter. I was convinced that the power supply board (BN44-00280A) was bad so today I replaced it. No change after the replacement. Not sure if it is related, but prior to the shutdown the plasma screen has intermittent static sounds. This may be normal, but it just doesn't sound right. Besides this when the set is on, the picture looks normal.

Any help diagnosing the problem would be greatly appreciated.

[Tony2706]

Re: Samsumg Plasma 58" PN58B540 PowerSupply Shutdown

Update: Power supply remains on when both the Y and X cards are not plugged in.

Voltages from PS to main board:
VS_ON: 3.2
PS_ON: 0.08
GND: 0.0
GND:0.0
5.3V: 5.11
5.3V: 5.11


Voltages on X output:
1:VS: 205
VS: 205
GND: 0.0
GND: 0.0
15V: 14.9



Voltages on Y output:
VS: 209
VS: 209
GND: 0.0
GND: 0.0
15V: 14.9
VA: 54.3
VA: 54.3

[freakaftr8]

Re: Samsumg Plasma 58" PN58B540 PowerSupply Shutdown

Try one bard at a time, leave the Y sustain connected, run the tv, if it shutsdown, connect z, leave y disconnected. Of course there will not be a screen..

[Tony2706]

Re: Samsumg Plasma 58" PN58B540 PowerSupply Shutdown

In both cases the tv shuts down (Y alone and Z alone). During both tests the audible popping sounds were more prevalent.

[Tony2706]

Re: Samsumg Plasma 58" PN58B540 PowerSupply Shutdown

Ok. Based on reading another thread and a hunch, I unplugged the touch button and IR input to the control board. Now the tv has been running for 15 minutes with both the Y and Z connected. Good screen output. This appears to be a bad IR or push button or maybe the control board itself. Any suggestions on how to isolate the problem?

[Ltank]

Re: Samsumg Plasma 58" PN58B540 PowerSupply Shutdown

Piping from the speakers or capacitors? If so which boards? Any evidence from boards?

[Tony2706]

Re: Samsumg Plasma 58" PN58B540 PowerSupply Shutdown

Yes it appears so. The left side aluminum bracket will arc to the multimeter probe. I unplugged the speakers and it is still there. This leaves the Y sustain and its buffer. Any suggestions to find the shorting?

[Tony2706]

Re: Samsumg Plasma 58" PN58B540 PowerSupply Shutdown

There appears to be a conductive tape running the length from top to bottom. Has a charge on it. I do not see anything similar on the right side. Is this expected?

[Tony2706]

Re: Samsumg Plasma 58" PN58B540 PowerSupply Shutdown

Is there any tricks on removing the tv control button board? I removed the hot glue dots but appears to be glued in also.

[Tony2706]

Re: Samsumg Plasma 58" PN58B540 PowerSupply Shutdown

Here is some more info that might help.

Attached is a large view of the back of the TV. The issue I am having is on the lower left of the picture. The second image is a close up of the button control module. On the side of the aluminum frame you can see the conductive tape (at least that is what I think it is). The voltage is hard to determine with the DMM. It appears to be fluctuating. Is this normal to have a voltage on the tape?

I have disconnected the button control module from the main board and it is still powered. I believe this is coming from the charge on the conductive tape since I do not see anywhere else that the button control module could be getting any power. As soon as I plug the assembly into the main board, the tv shuts down.

Any troubleshooting ideas would be greatly appreciated! Thanks for all the help to get me this far.

[dysplastic]

Re: Samsumg Plasma 58" PN58B540 PowerSupply Shutdown

Did this one ever get solved? I have the same problem with mine.

[dysplastic]

Re: Samsumg Plasma 58" PN58B540 PowerSupply Shutdown

Here is some more info that might help.

Attached is a large view of the back of the TV. The issue I am having is on the lower left of the picture. The second image is a close up of the button control module. On the side of the aluminum frame you can see the conductive tape (at least that is what I think it is). The voltage is hard to determine with the DMM. It appears to be fluctuating. Is this normal to have a voltage on the tape?

I have disconnected the button control module from the main board and it is still powered. I believe this is coming from the charge on the conductive tape since I do not see anywhere else that the button control module could be getting any power. As soon as I plug the assembly into the main board, the tv shuts down.

Any troubleshooting ideas would be greatly appreciated! Thanks for all the help to get me this far.

Hi Tony, did you ever solve this problem?