Plasma TV - any ideas on getting it working?

Oh, just discovered something...

When you press the power button, nothing happens for about 5 seconds (bootup). After this the buzzing happens. HOWEVER, the buzzing is at two pitches and changes at ~2second interval. At the same time, if I look down the back, theres a red LED that alters in intensity in time with the buzz.

I'm assuming then that a startup 'test' has failed, and that this is an indicator of the problem. I'll open the back up this weekend and see if theres anything marked around the LED that can indicate the exact issue.

Hope that may help anyone in the know - I'll also update this thread just incase it comes in handy for anyone else out there on the interweb.

Ta!

Danabnormal

snipped-for-privacy@turnitoffandon.co.uk ha escrito:

Sounds like the power supply has shut down due to a short or other problem. This set will need proper troubleshooting. If you haven't the relevant experience or tools, I strongly suggest you NOT try to do it on the cheap and do not tamper with it. You could endanger your life and mess it up beyond economical repair. A trained tech OTOH, after removing the rear panel, will easily be able to identify this fault and give you an idea of how much it will cost to proceed. I recommend you TAKE it to a repair shop!

-B.

Heya.

Cheers for that - I fully intend to, but if I can save myself =A380 for someone to diagnose the fault and tell me its buggered, that'd be my preferred option. ;) I'm no electrician, and have no intention of tinkering, but if I can find a model number inside (as I'm assuming this is a 'generic' model) I can hopefully find a manual that'd tell me exactly what that light means.

Cheers for the reply!

I'll hazard the guess that it's got a power supply that's failed, probably a switcher. The buzzing noise(s) are the supply trying to get going. The failure could be the power supply itself, they do that - just crap out for no reason, well bad caps, failed component, etc, or the supply is not starting because of a fault in the rest of the circuitry. Finding tech docs for this could be problematic. It's probably from China and having been rebadged makes it trickier. If you can find out where it was originally purchased the store may have some info or an "authorized" repair depot. Although a lot of them won't sell or give info to the general public. Here in the states even companies that used to be real good about making service literature available are dropping that business. A good tech may be able to ascertain the problem even without docs and fix a power supply as long as it isn't a unidentifiable/unavailable part. If the problem is part of the main circuitry - you may be hosed. That kind of good tech won't come cheap, but won't be a rip off either. Good luck.

tomh

snipped-for-privacy@turnitoffandon.co.uk wrote:

To start with, open it up and see if there's craters in any of the big chips bonded to the panel, if that's the case (as was with the Sony I looked at once) then it's not worth working on.

Hiya guys.

Cheers for all the replies so far - thought I'd drop you an update.

I have opened up the back of the unit, and theres no markings or obvious signs of blowout on any chip, board, or component.

The light I refer to above appears to be part of 5 lights that look like they're there for diag purposes - once the power button is pressed, all light up, and then turn off one by one barring this one, which then begins to flash.

On closer inspection, the buzzing sound I mentioned seems to be coming from the screen as apposed to any one component (this is a guess - but I have been unable to pinpoint a source of the sound, it appears to come from the entire surface area once the back is open).

I'm thinking this is not the PSU that has blown - on pressing the power button the light on the power switch goes green, and you also get that familiar 'click' from the PSU, followed by a bootup pause, followed by this LED and buzz. I'm gonna open it again and try to take some pics of the boards and model numbers.

Thanks!

Dan