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shortpin to turn a motherboard on

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Lorenz.zulu

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Hi everybody!
I have my laptop motherboard in front of me and I'm trying to figure out how to turn it on without Power button and ribbon cable.
There is a connector called JSW1 (switch) with 8 pins where to put in the ribbon cable. This connector has the following diagram:

2j2stts.jpg.png


I just want to short the pins on the base of this connector in order to turn my motherboard on. But which pins? Surely the second one and then?
Someone has told me to solder a small wire to the second pin and connect it to the ground (areas where tightening screws in the motherboard can act like ground). But I just had a small bipolar cable (like those of stereo headphones) and so I've tried with the ground of this cable (excluding the white and red wires), without soldering anything.
I've connected one end to the nearest screw slot (for the ground pole) and the other one to the second pin (being careful not to touch the first or the third pin). But all I've got is a spark and some burn on the pin. Perhaps, the ground of my audio cable wasn't suitable for this task or perhaps a solder to the pin is needed (it would be a micro-solder and I don't have any solder for this).
I just don't want to use a solder but find an "on-the-fly" solution to turn the motherboard on. Someone has used a flat screwdriver to shortpin (normally a couple of pins for other laptop models) but I've seen on the internet that those people use the ribbon cable to do that (perhaps to avoid sparks and burn on the pins located on the base of the connector).
Any idea about this issue?
 
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KlausST

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Hi,

It's guessing.
You have to try it. But not to kill your motherboard i'd not do a hard short, but use a series resistor. Maybe 100 ... 1000 ohms.

Klaus
 

ads-ee

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But all I've got is a spark and some burn on the pin. Perhaps, the ground of my audio cable wasn't suitable for this task or perhaps a solder to the pin is needed (it would be a micro-solder and I don't have any solder for this).
Sparks and burned pins means you made a short between the power rail and the ground rail. If that short was between power and something that is driving to ground you may have blown the output of that driver. You shouldn't randomly try shorting connections together without know exactly what the signals do. Either solder wires to the pins and run them out of the laptop and monitor all of them when pushing the power button or get the schematic of the motherboard.

But considering you've already had sparks there's the possibility you've killed it already.
 

SunnySkyguy

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A better solution to go to Power Management in Control Panel to advanced options and disable LID switch function instead of sleep.

- - - Updated - - -

But prudent designs will use logic low to a pullup termination. A volt meter would verify the levels.
 

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