Re: Philips DVP642 DVD player not starting up

"BW" <boneywasawarriorvayayixSPAM@xxxxxxxxxxxxx> wrote in message
news:YxFUe.20705$I02.1379115@xxxxxxxxxxxxxxxxxxxxxxxx
> Hi all,
>
> I bought a Philips DVP642 DVD player less than an year ago. I had been
> playing DVDs and CDs nicely till a few days ago. I watched a DVD movie
> on it last weekend, and after that I wanted to play some mp3s on it on
> wednesday. When I clicked the eject button on it, it came out of power
> down mode, and I heard a chirp sound in the speakers and it went back to
> power down mode again.
>
> I tried it a couple of times and got the same reponse. I pulled the plug
> and let it rest for a while and tried again. Response was same!
>
> Does anyone know where to get the service manual for it? Or does anyone
> have some other tips for me? Except the advice of sending it back to
> Philips. I would prefer to make it work myself if it is just some
> configuration setting which needs to be reset.
>
> Thanks in advance,
> /KS

Hmmm.

Lots of advice, but not much of it very helpful.

Almost all of the Philips DVDs that I've ever repaired, irrespective of
model, have had a similar fault, and this is one of the PSU secondary side
Schottky diodes short circuit. This may not be the case with your machine,
and I agree with some of the other posters that, for the most part, DVD
players are not worth wasting time on, but it's got to be worth five minutes
of your time with an ohm meter just in case.

Just a word on safety. Remember that this is a switch mode power supply,
which is POTENTIALLY LETHAL. Do not check it or work on it live, unless
doing so on a proper workshop isolation transformer, and even then only with
care, and beware of the main smoothing cap on the primary side, remaining
charged, as it can do on a switcher that's not starting up. Won't kill you,
but may result in a smashed board where you involuntarily sling it against
the wall ... !!

When checking Schottky diodes, remember that they have a significantly lower
forward resistance than silicon types, but will still have a virtually
infinite reverse reading. Any diode that reads low both ways should be
considered suspect, but confirm that by unplugging the PSU output plug, as
you can be fooled by reading across the VFD heater.


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