Question Testing a power switch cable ?

Phosphonothioic

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Dec 20, 2012
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What’s the easiest way to test the cable that connects the power switch to the motherboard? I wasn’t able to get my computer to start after a rebuild, but my PSU checks out and I can jump the power switch pins on the MB with a trusty screwdriver.

EDIT: And why am I having such a hard time posting images? The hosting sites are giving me stuff like
https://ibb.co/FLpWHzbk which I know is supposed to go under the media upload, but that’s not working either. And, for some reason, I can’t get the sites to give me a link with a .jpg/etc directly.
 
What’s the easiest way to test the cable that connects the power switch to the motherboard? I wasn’t able to get my computer to start after a rebuild, but my PSU checks out and I can jump the power switch pins on the MB with a trusty screwdriver.

EDIT: And why am I having such a hard time posting images? The hosting sites are giving me stuff like “https://ibb.co/FLpWHzbk”, which I know is supposed to go under the media upload, but that’s not working either. And, for some reason, I can’t get the sites to give me a link with a .jpg/etc directly.
A multimeter would be the obvious choice. The on button is a momentary connection between the two wires. That would be easily seen on a multimeter. You may have to use short pieces of wire to get connectivity into the pin sockets.
 
What’s the easiest way to test the cable that connects the power switch to the motherboard? I wasn’t able to get my computer to start after a rebuild, but my PSU checks out and I can jump the power switch pins on the MB with a trusty screwdriver.

EDIT: And why am I having such a hard time posting images? The hosting sites are giving me stuff like “https://ibb.co/FLpWHzbk”, which I know is supposed to go under the media upload, but that’s not working either. And, for some reason, I can’t get the sites to give me a link with a .jpg/etc directly.
Incidentally, the header on the motherboard itself will just be the actual switch wire for one wire, and a ground for the other wire. Momentarily shorting the two wires (or the one to some ground) triggers motherboard power. If you are careful and do not short the wrong pins, then you can see something as simple as a small screwdriver momentarily shorting the two pins starts the computer.

If there is a wire attached, and you have two wires at the remote end, then the same thing is true: A momentary short should cause the computer to start (just be very careful it really is the "start" pin being shorted to ground...nasty things happen if you get the wrong wire). If it fails, then either the hot wire or the ground wire don't work.

If the cable up to the switch can be momentarily shorted and cause a start, but the switch itself doesn't cause this, then the switch is probably bad. The power load is so low though that it is hard to imaging a chassis power button actually wearing out even after a couple of decades.

Note: Someone edited this, don't know what is missing.
 
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What’s the easiest way to test the cable that connects the power switch to the motherboard? I wasn’t able to get my computer to start after a rebuild, but my PSU checks out and I can jump the power switch pins on the MB with a trusty screwdriver.

You almost answered your own question.

If it works with your trusty screwdriver and not with the switch, the only thing that could be broken is either the cables or the button itself.

The power button of a computer always is a momentary normally open switch nowadays. which means, it only connects the two wires and sends a signal from one end to the other, when you push the button. You could inspect the button. If it is mechanically functional., the only problem left should be the cables. Then your only option left is a replacement.
 
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You almost answered your own question


If it works with your trusty screwdriver and not with the switch, the only thing that could be broken is either the cables or the button itselve.
The power button of a computer always is a momentary normally open switch nowadays. which means, it only connects the two wires and sends a signal from one end to the other, when you push the button. You could inspect the button. If it is mechanically functional., the only problem left should be the cables. Then your only option left is a replacement.
Lian-li doesn’t sell a replacement front I/O panel, which includes the power switch, obviously. I’m worried I’m going to have to junk a whole case because the switch and/or wire are broken. I’ve been searching Amazon for replacement cables, but have only seen cable/button assemblies that, while certainly financially appealing, would require a non-zero amount of modification to the case.

Wish I could get the damn photo to post. If I could find the cable itself, I’d just replace that.
 
The cables are probaly very easy to find. Any jumper cable on amazon can probably handle that amount of electricty. If you have very basic soldering skills, you could replace those cables. Maybe you don´t even have to solder them. Some I/O panels have pins as well. I hope that you can upload a photo soon or find one online and send a link. Please send a link to the case or the name of the case.

I’m worried I’m going to have to junk a whole case because the switch and/or wire are broken.
I wouldn´t do that. Even if you like the aesthetics, you can still just hook up a different buttton and pull the cables through a slot at the back.
Something like this for example

Power button example
 
The cables are probaly very easy to find. Any jumper cable on amazon can probably handle that amount of electricty. If you have very basic soldering skills, you could replace those cables. Maybe you don´t even have to solder them. Some I/O panels have pins as well. I hope that you can upload a photo soon or find one online and send a link. Please send a link to the case or the name of the case.


I wouldn´t do that. Even if you like the aesthetics, you can still just hook up a different buttton and pull the cables through a slot at the back.
Something like this for example

Power button example
IMG-0310.jpg

There’s the cable I’d have to replace. I’m using the Lancool II case.