TV goes dim then switches off?

[AliRidha]

Hi guys i have a 32' Vistron tv and for some reason after a few minutes of switching it on the top part of the tv goes dim then the screen switches off even though it still has a green light showing it on, i have to switch it off then on to get it working again.
this is the first time it has happened and has occured 4 times while writing this question

 

[Shaun o]

The problem is common with most Lcd based tv`s and computer monitors, if not of a well known brand.
And the reason why in most cases is because of the electronic components used to make the power board and the video decoder board. on cheaper branded sets the components used will be cheaper quality.

Anything from turning on the tv, and it not showing an image, to the back light dimming then the screen turning off in operation is a problem in most cases with the power board section internal to the Lcd tv.
The main culprits, or the most common are bad capacitors on the power board.
If you open the Tv up and locate the power board a simple inspection of the capacitors and the state they are in can be seen visually. The sign of a bad capacitor can be that other than it being flat it is domed on its top surface, or on its lower surface where it is soldered to the circuit board.
A sticky liquid may also be present.
In any of the two cases each capacitor should be replaced with the correct state voltage value, and micro farad rating that is printed on the side of the capacitor.
Capacitors can be bought from most electronics stores such as tandy, Radio shack or any online electronics component supplier such as RS.
Remove the bad capacitors, de solder, taking note of the polarity and position they are soldered to the board.
Denoted by a stripe, on one side of the capacitor.
Place your new ones, the same way as each is denoted.
Solder to the board.

And in most cases it resolves when a tv is turned on but fails to produce a visual picture, or if the display, back light goes off after a few seconds or minuets of operation.

The problem, starts to happen with any tv or monitor over about three to four years of use.

It`s not the hardest thing to do, you just need to open up the Tv, get the correct new capacitors for each of the old that look worn or damaged.

And have a solder iron, solder and flux for very little cost.

 

[AliRidha]

The problem is common with most Lcd based tv`s and computer monitors, if not of a well known brand.
And the reason why in most cases is because of the electronic components used to make the power board and the video decoder board. on cheaper branded sets the components used will be cheaper quality.

Anything from turning on the tv, and it not showing an image, to the back light dimming then the screen turning off in operation is a problem in most cases with the power board section internal to the Lcd tv.
The main culprits, or the most common are bad capacitors on the power board.
If you open the Tv up and locate the power board a simple inspection of the capacitors and the state they are in can be seen visually. The sign of a bad capacitor can be that other than it being flat it is domed on its top surface, or on its lower surface where it is soldered to the circuit board.
A sticky liquid may also be present.
In any of the two cases each capacitor should be replaced with the correct state voltage value, and micro farad rating that is printed on the side of the capacitor.
Capacitors can be bought from most electronics stores such as tandy, Radio shack or any online electronics component supplier such as RS.
Remove the bad capacitors, de solder, taking note of the polarity and position they are soldered to the board.
Denoted by a stripe, on one side of the capacitor.
Place your new ones, the same way as each is denoted.
Solder to the board.

And in most cases it resolves when a tv is turned on but fails to produce a visual picture, or if the display, back light goes off after a few seconds or minuets of operation.

The problem, starts to happen with any tv or monitor over about three to four years of use.

It`s not the hardest thing to do, you just need to open up the Tv, get the correct new capacitors for each of the old that look worn or damaged.

And have a solder iron, solder and flux for very little cost.

thanks you helped alot, now that i found the problem i think am just going to throw it and buy a proper tv like LG or Samsung, and you were correct about how long ive had it: i had it for about 3 years.
i have also noticed that the screen gets very hot when its about to switch off