TV only turns on with hairdryer(?)

It might be fixable if you have an hour

Most lkely it is a dry joint on one of the boards

Some flux and a heat gun could fix it , if you have the time , skills

Bulging caps would be the first thing to check
 
FARGO;30484439 said:
Random one but I have a Samsung PS42A456 plasma TV that I've got a good bit of use out of over the last ~9 years.

However, for the last three months it won't turn on unless I heat the 'innards' through the back panel vents with a hairdryer. When switched on at the wall, the red standby light illuminates momentarily then goes out and the tv is unresponsive - it will only come to life if I go through the above method, every time I power on at the wall.

I've tried different fuses, different power leads and also a factory reset. Aside from leaving it plugged in and turned on at the wall (which I'm reluctant to do) is there anything anyone can recommend? It's done be proud over the years!

I believe it may be an issue with the capacitors being old and swollen - and I don't have the savvy to fix such things if that's the case :(
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Sounds like you have one or more dry joints on the PCB.

Have you looked to getting it repaired?..would be cheaper than a replacement.

The Samsung Red Rose LCD's had a similar issue few years back, red stand-by light would flash and take anywhere between 10-15 mins to come on lol and was down to dry joints.

After 9 years i'd say you've had your monies worth though! :p
 
I've definitely had my monies worth! The annoying thing is that other than the process of turning it on, the set is fantastic and it'd be a shame to get rid if there's a relatively simple remedy.

I'll have the back off over the weekend and see if there's anything clearly amiss :)
 
If you are going to attempt to locate the fault by taking the back off, unplug the TV overnight. After you take the back off, plug back into the mains to check the standby light is not lit. Assuming it's not lit, you can test if it's a dry joint (not so likely in my opinion) by gently tapping the PCBs with something like the plastic handle of a screwdriver. If tapping one of the PCBs brings the TV back to life (standby LED lights up), then it would indicate a dry joint.

If there doesn't seem to be a dry joint, I'd start by carrying out a visual inspect for dodgy capacitors. This is the kind of thing you are looking for : http://electronics-diy.com/schematics/1260/repairing-switching-power-supply-3.jpg or even http://www.pcstats.com/articleimages/200302/capblown_6.jpg

If you see any capacitor(s) like those in the photos, try gently heating them up with your hairdryer. You will probably find that the TV starts to work properly very soon after the faulty capacitor(s) warms up.

Obviously be very careful when working on the TV with the cover removed. And if you know how to solder and are capable of replacing faulty components, you'll know the danger of charged capacitors.
 
Thanks for the very detailed explanation. I'll read a bit more around the topic before considering attempting a home fix.
 
FARGO;30487167 said:
Thanks for the very detailed explanation. I'll read a bit more around the topic before considering attempting a home fix.
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Last time I checked (ages ago), a TV repair guy would charge around £40 to inspect the TV and give you a report on what needs doing.
 
FARGO;30487167 said:
Thanks for the very detailed explanation. I'll read a bit more around the topic before considering attempting a home fix.
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If you aren't handy with a soldering iron, or don't feel confident in carrying out the repair, you could try to locate the fault and take the PCB to a TV repair shop/company (if you can find one) and ask them to do the work for you. If it is a capacitor, or even a dry joint, they should be able to do the job very cheaply for you, as they haven't got to do the fault finding or even guarantee the repair. You would obviously have to remove then replace the PCB yourself, but that should be reasonably easy.
 
SC0TTRS;30487176 said:
Last time I checked (ages ago), a TV repair guy would charge around £40 to inspect the TV and give you a report on what needs doing.
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or he could probably buy the board for £40 and just swap it out then take his old board to a pro to be fixed for a couple of quid as a backup.

he already knows the board is knackered why pay £40 for someone to tell him his board is knackered?
 
As others have said it's probably just a capacitor. We had a tv that wouldn't turn on but worked fine once it did.....after lots of power button pressing that is.

Should be able to spot one easily.
 
Leaving it on standby would be far cheaper to run than turning it off at the wall then using a hairdryer to heat it up to turn it on.
 
The only problem with leaving the TV in standby 24/7 is that eventually the faulty capacitor (if it is a faulty capacitor) is likely deteriorate to the point that after a power cut it will not be possible to revive it with a hairdryer. It should be a lot easier to pin down the fault while the capacitor can still be brought back to life with heat.

In a previous life I used to repair TVs, VCRs and satellite receivers. A common fault with early (analogue) Sky boxes was that the power supply would fail after the mains supply was removed then restored, quite often causing a small explosion and a fair bit of damage. It got to the point that we would warn customers about the risk of removing power from a Sky box before carrying out any other work. If we suspected that a Sky box was on the brink of self-destructing, we'd recommend that some of the capacitors in the power supply should be changed. There were kits of capacitors available that would prevent PSU damage, and I fitted quite a few before Sky Digital came along.
 
Psycho Sonny;30487356 said:
he already knows the board is knackered why pay £40 for someone to tell him his board is knackered?
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And we know this how?! From a few speculative comments on a general forum? Everyone is just guessing.. the OP doesn't know what the issue is otherwise he wouldn't be asking!
Forgot every OCUK forum member is a qualified TV repair technician along with a string of other keyboard qualifications. :rolleyes:
 
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