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Philips DVD Power Board Short Circuit - NEED ADVICE

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Hello
I need your advice on a (probably) simple case of short circuit on the power board of my Philips DVP5990/12 DVD player.

How it occured
My DVD player is powered from mains all the time and sits in stand-by mode. I pressed as usual on the Power button on my remote to start it. A brief flash and pop sound came from inside my DVD and apartment mains fuse jumped.

I removed the cover and I found the fuse blown and the TinySwitch TNY176 IC exploded (U1 on schematic below).

**broken link removed**

I took several high resolution photos of the power board to see it for yourself. See photos in here.

My questions for you are:

1) What component do you think 'cracked' first and why?
2) What other components (other than fuse and U1) may be faulty?
3) Is it possible this fault affected the mainboard of DVD?
4) What can I do to prevent a similar event in the future?

Thank you for your time.
 

I found out that D1 and D3 are shorted.
Does that help you to answer my questions?
 

Check every component in power section for short or open using multimeter. It may be happening due to power surge better use stabilizer device for valued appliances.

- - - Updated - - -

And use 60W bulb in series when checking power board live with supply it minimizes further shorting of components while checking.
 
Check every component in power section for short or open using multimeter. It may be happening due to power surge better use stabilizer device for valued appliances.
I checked all components, the rest are good.
Yes, we had a few power downs, your advice makes sense.

And use 60W bulb in series when checking power board live with supply it minimizes further shorting of components while checking.
You mean after replacing bad components?
On the other hand, the mains fuse is slow 2 Amps(!). To me it looks over-dimensioned and it explains why blew up last and my apartment fuses jumped. Any ideas?
 

Yes after replacing bad components you can use a 60w bulb in place of Fuse to check there is shorting some where or not , if Bulb stays ON steady there is still something short. if bulb Get ON for While and OFF quickly its good sign that there is No Short on Primary side of Power Supply.
 
The charred yellow component looks like an MOV (varistor). It is designed to conduct when exposed to a high volt level. It is supposed to protect other components from overvoltage.

You'll have to replace it.

It's likely there was a lightning surge, etc. Then when you powered up the unit later, another surge went through more components.

Even if you replace the MOV, there appear to be other bad components on the board. You might replace those, yet still not get the board to work.

I found out that D1 and D3 are shorted.

If you are very lucky, the surge did not travel further than these components. If you replace them (and whatever else is charred), you might manage to restore operation, if you're lucky.
 

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