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Thread ID: 150915 2022-10-01 07:56:00 weird Tv behaviour - maybe just old age Tony (4941) Press F1
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1488670 2022-10-01 07:56:00 My tech challenged neighbour has an oldish 40" Samsung TV that has started misbehaving. When she powers it on the standby light flashes but nothing else happens. Then it stops flashing, then maybe starts again. Eventually after a long time (30+ mins sometimes) it staggers into life. At that point it can be turned off and on again with no issues - until she shuts it down overnight, whereupon the behaviour starts again the next time. That sort of makes me think it is some kind of warm-up issue, but I know no more.
Is this any sort of known problem with an easy fix? She has just about given up and my own technical analysis is that it is probably munted, but I'd like to kick it back to life for her if it can be done.
Tony (4941)
1488671 2022-10-01 08:32:00 Try giving it judicious bumps with your closed hand using the bottom part of your fist to see if there is a bad solder joint whilst it is switched on but not starting, don't bump it too forcefully of course, just small knocks.

Try along the edges of the unit, not the screen of course and also lighter knocks around the back surface.

Whilst it is running see if you can make it turn off by knocking it gently.
zqwerty (97)
1488672 2022-10-01 14:00:00 Failing capacitors in the power supply, most likely.
Possibly some other part with a thermal fault but the symptoms you describe are classic of marginal capacitors on their way out.

When cold, the ESR goes up, they don't work properly. After a time they warm up enough that the ESR drops to acceptable limits and it starts working.

You'd need to replace them. If you can solder, it's not a hard job. I've done it before in TVs, monitors, etc.
Agent_24 (57)
1488673 2022-10-01 18:17:00 Failing capacitors in the power supply, most likely.
Possibly some other part with a thermal fault but the symptoms you describe are classic of marginal capacitors on their way out.
That sounds entirely plausible. It is beyond my soldering capabilities though. I think she has already decided she wants to change the box anyway, but I'll suggest she could try taking it to Teletech.
Thanks.
Tony (4941)
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