Proscan 40LC45S57 with red LED and clicking.

[mattd1979]

The TV model is Proscan 40LC45S57. What happens when I plug it in is I here a repetitious high pitch wine pulse as the LED stays constant red and you here the speakers popping and the relays inside clicking in sync. I removed the back cover to do a visual inspection to see if there were any blown capacitors or burnt ICs but couldn't tell visually. I decided to go ahead and disconnect the cable that runs from the power board over to the back light inverter. After disconnecting the inverter cable and reconnecting the power cord, I saw a red LED on the power board come on(was previously not lit.) and the red LED on the front of the TV switched off and a blue LED switched on. I then grabbed my flash light and shined it through the back side of the LCD panel and I could see that the "No Signal" message was displaying. So apparently there must either be a short in the inverter board or do you think that maybe the power supply isn't strong enough to supply power to the inverter and it is cycling? I had also noticed that when I turned the TV off there is a high pitch wine coming from what looks like the smaller of the two transformers on the power supply board.

What can I do at this point to determine which board is the problem? Could it have both a bad inverter and a PSU board?

Thanks,
Matt

[dcapper]

Re: Proscan 40LC45S57 with red LED and clicking.

Does the panel have the voltages on a sticker on the panel? Unhook the cables from the power supply and meter the voltages. You could still have a bad cap. Meter those too if you have a cap meter. The whine you hear could be a draw on the power supply. The inverter could be shorted causing the whine. Does the whine stay if you disconnect the inverter from the power supply?

[mattd1979]

Re: Proscan 40LC45S57 with red LED and clicking.

The wine sound is sounds like a high pitch ghost busters siren like that of a mouse. When I unplug the inverter and plug the power cord back to it, it becomes a steady high pitch sound like that of an old CRT TV when it is off but goes away once turned on. Also the unit will fully power up and I can see the "No Signal" message dancing around the screen if I take a flash light and shine in through the back. The voltages are stencil screened onto the board. I have included some attachments of the board and a close up of the connector that feeds the inverter. I removed the inverter cable from the PSU and powered it up. I found that all of the 24V legs on the connector read 24V. The SW leg reads 4.7 and the PWM leg reads 2.5V.

[budm]

Re: Proscan 40LC45S57 with red LED and clicking.

Show us good clear pictures of the inverter board, also straight shot pictures of the power supply board.

[mattd1979]

Re: Proscan 40LC45S57 with red LED and clicking.

I have attached some more pics of the PSU board and inverter board. I don't have a cap tester so unable to test them.

I tried taking the pics in such a way that you could lay them out together to create one big picture.













Here are the PSU board pics.

[mattd1979]

Re: Proscan 40LC45S57 with red LED and clicking.

Anybody have any ideas? Bad PSU or bad inverter?

[mattd1979]

Re: Proscan 40LC45S57 with red LED and clicking.

I have noticed that there seems to be more people in need and not enough people that are knowledgeable enough to help. I say this because in just a day's time a single post can end up on a second page and unless someone actually decides to move to the next page to read the post to help, it is lost. So, I have posted again to keep it close to the top and noticeable to those who do or may know the cause of said problem.

[mattstolte]

Re: Proscan 40LC45S57 with red LED and clicking.

I have noticed that there seems to be more people in need and not enough people that are knowledgeable enough to help. I say this because in just a day's time a single post can end up on a second page and unless someone actually decides to move to the next page to read the post to help, it is lost. So, I have posted again to keep it close to the top and noticeable to those who do or may know the cause of said problem.

If you have 24 volts going to the inverter and the inverters not turning on, then the only thing it could be is inverter.. because u said u seen the no signal sign. So that shows ur main and tcon are working correctly. Goto ebay get a cheap inverter and try it.

[budm]

Re: Proscan 40LC45S57 with red LED and clicking.

OK, so the fuses on the inverter board are good? Check and see if they have 24Cdc on both ends of the fuses.

[mattd1979]

Re: Proscan 40LC45S57 with red LED and clicking.

According to the printing next to the two fuses on the inverter board, they are both 125v at 7amps. Are there fuses somewhere else that I don't see? I did check for continuity on those two fuses and they ohm out good. As for power, the PSU board will not power up as long as it is connected to the inverter board. It keeps rebooting very fast.

[budm]

Re: Proscan 40LC45S57 with red LED and clicking.

"As for power, the PSU board will not power up as long as it is connected to the inverter board. It keeps rebooting very fast." OK, it is either that the inverter is drawing too much (shorted MOSFETS, CAPS, ETC.) power which will cause the power supply to go into shutdown mode to protect itself, or the 24V power supply has problem.

[mattd1979]

Re: Proscan 40LC45S57 with red LED and clicking.

That is the delima I am facing. Trying to figure out which is the actual problem so that I don't end up buying extra parts.

[mmartell]

Re: Proscan 40LC45S57 with red LED and clicking.

mattstolte already answered your dilemma in post #8.

[mattd1979]

Re: Proscan 40LC45S57 with red LED and clicking.

I just didn't want to go and by an inverter just to find out that the real problem was with a failing power supply board.

[mattd1979]

Re: Proscan 40LC45S57 with red LED and clicking.

Will the following work as a substitute for the inverter that I have? Mine is a INV40N14A and the longer set of numbers above it is 02098ac91906253a1 on my board. The one below is INV40N14B.

http://www.ebay.com/itm/Westinghouse...item3f28f62861

Also, is there a way to put a load on the PSU board to mimic the inverter connection to see if it still trips out?

[RJARRRPCGP]

Re: Proscan 40LC45S57 with red LED and clicking.

The wine sound is sounds like a high pitch ghost busters siren like that of a mouse.

That reminds me of the sound of death on laptop PSUs!

[mattd1979]

Re: Proscan 40LC45S57 with red LED and clicking.

Is there anyway I can test the inverter or the PSU board independently? If so then please give me some instruction on how to go about proceeding. Thanks

[mattstolte]

Re: Proscan 40LC45S57 with red LED and clicking.

Ok if the power supply will not power up as it is connected to inverter then there's proly a short on inverter cause if it will power without it. Then inverter is shorting it down. U can goto shopjimmy to look up ur part number

[mattd1979]

Re: Proscan 40LC45S57 with red LED and clicking.

Just wanted to let everyone know that replacing the inverter indeed restored the TV back to operational standards. I found a good board on Ebay for $14.00 including shipping. It looked brand new and was well packaged.

I noticed on the backside of the original inverter board that it has three brown spots in the lower left corner area. On the front side of the board it has three small ICs under the large transformer. You can see them in the first picture of the group of pictures in post #5.