laptop motherboard : short circuited DC input

I have a laptop motherboard which suddenly had its DC input ends short circuited. It workded normally for hours and switched off normally. When trying to run it again some day after it won't boot up and I noticed that the DC input ends were short circuited.

Reply to
itt788
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Look for a big reverse power protection diode across the DC input connector. Also, if your battery charger is of the "universal" variety, look for the power being applied backwards.

If that's not it, I suggest you disclose the maker and model number, and if it works on battery power.

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Jeff Liebermann     jeffl@cruzio.com 
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Reply to
Jeff Liebermann

Plugged the wrong adapter into it?

Do you have others in the place that also likes to plug things into stuff like that?

It just sounds to sneaky..

Jamie

Reply to
M Philbrook

I wrote a bit too fast my message and I skipped some important information.

When I tried to boot up the computer and noticed it won't do I first checked the transformer and it showed the right voltage on the voltmeter screen. I also tried to draw some power using a fixed resistor which value was chosen to get something around 1 A and indeed the expected current values flowed within the resistor.

Then when trying to plug back it into the computer I noticed a big spark everytime I was trying to plug it in. That's when I noticed with an ohmmeter that the DC input ends were short-circuited. I also tested the battery, the voltmeter show a nice 0 Volt for each cell while it should fully charged.

I disassembled the computer and noticed that the short-circuit was caused by a MOSFET next to the DC input socket on the motherboard but after I replaced it, this new component also got killed and shorted the DC input ends.

Reply to
itt788

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