Broken TV, help with attemping repair.

lindos90

Hi, Im not sure if this should be here or in the tekkie forum, but hope someone can help.

We have a flat screen TV thats broken (it was on, then made a 'pop' and now does not come on at all, apart from a little red light).

My son is interested in seeing if he can mend it (nothing is lost if he cant, but he's interested in giving it a try and it would be a big achievement, as long as its not too expensive)

I know this maybe way beyond him, but are there any basic things he can check to start with, to try and identify the problem?

Things hes done so far:

-checked the fuse in the plug is working

-checked the power cable is working

-opened up the back, found a smaller fuse, took it to a shop for a replacement, they checked it and said fuse is fine

-looked at boards inside for evidence of shorting (burn marks etc), nothing obvious

-gently removed lots of dust!


Any help would be great, and of course I would supervise him doing anything thats suggested!

ormus

modern electronic equipment is not really suitable for diy repairs. you would need a fair basic knowledge of electronics first.
and test equipment. things like faulty capacitors are common failures.
if the PCB is faulty then the item is probably scrap.

the local tip is full of modern TVs, inc some very large expensive ones.

Inactive

lindos90 wrote: »

Things hes done so far:

-checked the fuse in the plug is working

-checked the power cable is working

-opened up the back, found a smaller fuse, took it to a shop for a replacement, they checked it and said fuse is fine

-looked at boards inside for evidence of shorting (burn marks etc), nothing obvious

-gently removed lots of dust!


Any help would be great, and of course I would supervise him doing anything thats suggested!

To be blunt, if he needed to take a fuse to a shop to have it tested, he really doesn't have a clue, I would leave well alone.

Electricity can be lethal in the wrong hands.

lindos90

Inactive wrote: »

To be blunt, if he needed to take a fuse to a shop to have it tested, he really doesn't have a clue, I would leave well alone.

Electricity can be lethal in the wrong hands.

Thanks for your advice. He took it to an electrical shop as it isnt a standard fuse, he just wanted to buy exactly the same one to replace it to see if it made any difference. It was actually the shop who offered to check it.

Point taken about messing around with electricity though!

OK_Sauce

I think the advice here is sound. He shouldn't really be messing around with electrical stuff. The fact the little red light was on would indicate the fuse and mains lead were ok so didn't need checking. If he hasn't grasped electrical fundamentals you could be left with more than just a faulty tv.

keystone

It'll be a blown capacitor most likely as Ormus suggests - its a very very common problem.

Get it repaired professionally - you can easily blow up the pcb by being overadventurous with a soldering iron or failing to take anti-static precautions.

Cheers

olias

OK_Sauce wrote: »

I think the advice here is sound. He shouldn't really be messing around with electrical stuff. The fact the little red light was on would indicate the fuse and mains lead were ok so didn't need checking. If he hasn't grasped electrical fundamentals you could be left with more than just a faulty tv.

Likewise, first thing that struck me, if the red light is on, it's getting power, why check the plug fuse and power cable?

I really am all for kids giving things a try and finding out how they work etc, and good on him for having a go, but....If he doesn't even realise that a light on the TV means there is power getting to it, then I really think he should stick to trying to fix mechanical things, and leave the electrics alone, try and encourage him along them lines.

Olias

McKneff

10 out of 10 for enthusiasm though:T:T

ormus

nomis21

I fixed my own as it was going to cost 80 just for an engineer to come out and look......!
Got info from googling and luckily there was a guy on ebay selling the required bits and bobs for less than a tenner.

Like said before capacitors are easily blown, you can tell this as they burst and buldge on the top....you need a steady hand with a soldering iron to take the old ones out and replace new ones, i replaced capacitors and still the tv would not power up....did more investigating and was hinted to replace the eprom....this is very tiny with 6 solder points and very hard to replace unless your good with a solder iron...anyhow got it up and running for less than 20 quid, would not like to thin how much a tv engineer would have charged me.!

Good luck and be careful

Ps capacitors can still hold a charge even if the tv is switched off.....dont make your hair stand up !

lindos90

Hi all, and thanks for the replies, obviously safety is the main issue, and I certainly wouldnt let him touch it without supervision, and obviously not plugged in.

My OH only remembered the red light after we had started checking things, so maybe we didnt need to check the plug or cable. But now he knows how to wire a plug, which wire is which, different fuse ratings etc. (With instructions to ALWAYS come to us before attempting to do anything and for us to check before using)

Sounds like we could be out of our depth here though, but wanted to get him thinking for himself, researching and trying to problem solve.

I guess I was hoping to get a good idea of what it could be and then 'steer' him towards discovering it himself. It would have done wonders for his confidence if he had!

My OH has access to soldering equipment at work, (mended my other sons DS last week) so if there ws an obvious capacitor he could have done it. Sounds like its going to be far to difficult though.

Thanks to again for all the advice, well appreciated!:T