LCD TV ?Overheating? - Solution?

_Maffu_

Hi folks,
I've been given a wharfedale LCD2610AF television which is just out of warranty.
It works fine when first switched on but after a while the screen breaks down into multicoloured vertical lines and eventually goes black. I noticed that it was giving off tremendous amounts of heat at this point and thought it may be overheating.
Sure enough, if you leave it to cool down you then get another 10-20 minutes out of it.

Why am I posting this here?
Well, the sudden appearance of an overheating problem this close to end of warranty smacks a little of built-in obsolescence and I would like to find a way to fix it without having to buy a new tv. I have thought about bodging a PC fan into it but I'm not sure where to take power from.
Any TV engineers out there able to offer a solution?
Thanks for your time.

Matt

davester

tell whoever bought it to try the shop , if its just out of warrenty then under sales of goods act you can claim that its was substandard to only last 1 year. TV should last longer than that according to Trading standards. So unless the TV has been opened then you souldnt have a problem proving it wasn't your fault i.e pouring coke down the back.

wuckfit

if you suspect components overheating, then the simplest way is to get a tin of freezer spray (maplin, rs, cpc etc) and spray suspect components when the unit is powered up. If the picture suddenly restores, you've found a duff component.

Be warned though, Lethally high voltages can exist inside any tv, so if you're in ANY doubt as to what you're doing then leave well alone.

computershack

Its not overheating, its got a failing chip. Could be any of them but when you've got the back off and with it running, feel round them and you'll find one thats red hot. When the fault occurs, spray that chip with a can of freeze spray and if it goes away, that chip needs replacing.

Now here's the bad bit - its usually not economically viable and soldering with a soldering iron is out.

aliEnRIK

You realise if its getting THAT hot it could go up in flames?

Inactive

aliEnRIK wrote: »

You realise if its getting THAT hot it could go up in flames?

My thoughts entirely..

_Maffu_

The heat seems to be coming from the backlights rather than the circuit board.

@Computershack the reason I suspected overheating is because, in my (admittedly limited) experience, chips either work or they don't - they don't work for a bit then give up, then start working again unless there is some other factor causing the failure, usually an environmental one like overheating. I thought that perhaps there was some internal heatshielding (I had a look and its all packed very tightly in there) that may have come loose and the heat coming off it seemed to back that up.

@alienrik and @Inactive It's not so hot that you could dry clothes in front of it or something. Mind you you've scared me now.

@davester I can't take it to the shop since the original owner (my mate who gave it to me) did that when it first went wrong and they told him to knob off. Had it been me I would have kicked up a stink but he just took it back home, bought a new telly and left this one unused in his spare room for six months. I had it off him as he was about to throw it in a skip and I thought it a shame for it to just get thrown if there was a chance of fixing it.

Oh well, unless any more replies come in in the next day or so, it looks like I'll just have to put my hand in my pocket for a new one.
Thanks everyone for taking the time to reply.

computershack

aliEnRIK wrote: »

You realise if its getting THAT hot it could go up in flames?

Really? Experience as a bench engineer tells me otherwise.....

And also in my experience as a bench engineer...chips DO work for a bit until they overheat. Been that way at least since the 1980's when I had my first job as a bench engineer repairing videogame mainboards.

aliEnRIK

computershack wrote: »

Really? Experience as a bench engineer tells me otherwise.....

And also in my experience as a bench engineer...chips DO work for a bit until they overheat. Been that way at least since the 1980's when I had my first job as a bench engineer repairing videogame mainboards.

Ive seen monitors on fire ~ and if you ask firemen im pretty sure theyll have a story or two to tell about tvs and the like

_Maffu_

computershack wrote: »

And also in my experience as a bench engineer...chips DO work for a bit until they overheat. Been that way at least since the 1980's when I had my first job as a bench engineer repairing videogame mainboards.

That's what I'm saying - if the chip itself was !!!!!!ed wouldn't it fry itself and stop working altogether? Whereas if it was merely being used in an environment where there was too much ambient heat (eg from faulty backlights) there would be a more gradual deterioration and the chip would start to work again once the enviroment cooled down? Also would one overheating chip be enough to make such a large unit radiate heat the way it does?
I'm not questioning your expertise here computershack - I'm trying to understand, clarify and perhaps clutch wildly at straws :0)

davester

Depends on the actual temperature the chip gets too, there was a nice video on Youtube of Pentiums vs AMD while playing Doom 3 and they removed the heatsink. AMD melted , Pentiums didn't just crashed