Vizio VP50 HDTV20A turns off unexpectedly

[awyea]

The tv would turn off after about 20 minutes of being powered on, although the picture is quite good when running. I took it apart and replaced 6 bulging on the power supply. All were 2200uf 10v, and I replaced them with new panasonic caps. I checked the Vs and Va, both are fine. I read about some cold solder joints, so I touched up quite a few solder points. The tv will still turn off after about 20 minutes or so.

Also, right after I replaced the caps, the tv stayed on for a good 2 hours or so until I turned it off. I figured this was a good test and put everything back together and moved the tv back upstairs. It is much cooler in the basement. Does the power supply have some sort of overheat protection? I'm lost.

[MagicSmoke]

Re: Vizio VP50 HDTV20A turns off unexpectedly

You will have to replace all of the low voltage caps. 25 or so in total.

I had to do this on my P50hdtv10a PSU.

What is the part number on your PSU?

[awyea]

Re: Vizio VP50 HDTV20A turns off unexpectedly

LJ44-00132B is the part number I think. I also found a bulging cap on the x board.

[tw2005]

Re: Vizio VP50 HDTV20A turns off unexpectedly

Similar samsung model with similar PSu had issues with cracked solder on the heatsinked FETS. i had one and it would randomly turn off, it could stay on for an hour,several hrs, all day.

when i flexed the board in the middle it shutdown, was fine after a reflow of the FETs, so i guess it depends on what you reflowed. The fets can blow from what i've read when it has these bad joints.

[awyea]

Re: Vizio VP50 HDTV20A turns off unexpectedly

Replaced all of the low-voltage caps, did a FET reflow again, still turns off after 5-10 minutes. Also, my green light has stopped coming on. Any other ideas?