Hello,
I trying troubleshooting my laptop, a purism librem15, which suddenly yesterday morning died, it doesn't charge the battery, and the power led is not lit.
I never tried to repair a laptop, but looking at the PCB, I was persuaded that the problem was just a burned out fuse. (https://pasteboard.co/JaVHnFq.jpg)
I started my troubleshooting convinced that that fuse could be the problem, but then I realized that despite a black mark it had on its surface, it was conducting.
Then I tried to verify a few things I learned reading here and there.
The MOSFETs after the power jack are conducting both, and I was able to read 19v on their drain.
The power rail coming from battery either is conducting, and I read 12v on all the MOSFETs involved with battery.
At the power button, I read 3v. (2.9 on my multimeter)
I read that I should have read 3.3v at the power button (not pressed) since the power rail 3VALW, feeding the SIO is such, and because the button is pulled up. In my case, I read only 3v, little less actually.
I was not able to identify SIO btw, I think it is embedded in the I7 companion chip, but I can't be sure.
I read somewhere the BIOS flash, in my case gd25q128c, is also fed by the 3VALW. The same source, for this reason, stated that I should have read on VCC 3.3v, but in my case, it was 0.
Can anybody give me a few hints on how to proceed with the troubleshooting? I also appreciate if someone could confirm my suppositions, or confute them.
Thanks for help
I trying troubleshooting my laptop, a purism librem15, which suddenly yesterday morning died, it doesn't charge the battery, and the power led is not lit.
I never tried to repair a laptop, but looking at the PCB, I was persuaded that the problem was just a burned out fuse. (https://pasteboard.co/JaVHnFq.jpg)
I started my troubleshooting convinced that that fuse could be the problem, but then I realized that despite a black mark it had on its surface, it was conducting.
Then I tried to verify a few things I learned reading here and there.
The MOSFETs after the power jack are conducting both, and I was able to read 19v on their drain.
The power rail coming from battery either is conducting, and I read 12v on all the MOSFETs involved with battery.
At the power button, I read 3v. (2.9 on my multimeter)
I read that I should have read 3.3v at the power button (not pressed) since the power rail 3VALW, feeding the SIO is such, and because the button is pulled up. In my case, I read only 3v, little less actually.
I was not able to identify SIO btw, I think it is embedded in the I7 companion chip, but I can't be sure.
I read somewhere the BIOS flash, in my case gd25q128c, is also fed by the 3VALW. The same source, for this reason, stated that I should have read on VCC 3.3v, but in my case, it was 0.
Can anybody give me a few hints on how to proceed with the troubleshooting? I also appreciate if someone could confirm my suppositions, or confute them.
Thanks for help
Comment