The schematics are here: https://www.badcaps.net/forum/showthread.php?t=69873 .
So, long story short, some tiny bit of water damage, and some visible corrosion around UC5, QC2 and some audio controller. Removed some of the corrosion with alcohol, but still no luck.
So all in all, the laptop turn on (screen stays black), but fans and leds start, for about 10s , then goes back off. After a few turning ons, the indicator led beeps an error code, which stands for "CMOS battery failure". I checked with another battery and still fine. The original battery has 3.36V so it's also fine.
So I started checking some voltages, I have 3.3V, 5V, 19V VIN.
I tried to follow the power on sequence, from page 38 in the schematics but I don't quite understand it.
Any tips on how to proceed?
There's this EC MEC1404-NU, which supposedly all the signals are going through, it gets powered. Initially I thought the PCH_RSTRSM# signal might be the issue, because of the water damage area on UC5, and the signal was 3.3V when powered-off, but it's an active low line so that doesn't seem to be it.
Thanks. (will keep this updated)
(I should note that I'm currently in the process of studying electronics, so I've built stuff like voltage regulators, buck converters, so I have a basic understanding of how some of the components work, but it's still very much a WIP (i'm using the Art of Electronics book). I realised that I need to further my understandings at a lower level so I started studying electrodynamics from Morrin Purcell book first. I'm a programmer by trade, but never had a lot to do with electronics before, other than physics competitions).
So, long story short, some tiny bit of water damage, and some visible corrosion around UC5, QC2 and some audio controller. Removed some of the corrosion with alcohol, but still no luck.
So all in all, the laptop turn on (screen stays black), but fans and leds start, for about 10s , then goes back off. After a few turning ons, the indicator led beeps an error code, which stands for "CMOS battery failure". I checked with another battery and still fine. The original battery has 3.36V so it's also fine.
So I started checking some voltages, I have 3.3V, 5V, 19V VIN.
I tried to follow the power on sequence, from page 38 in the schematics but I don't quite understand it.
Any tips on how to proceed?
There's this EC MEC1404-NU, which supposedly all the signals are going through, it gets powered. Initially I thought the PCH_RSTRSM# signal might be the issue, because of the water damage area on UC5, and the signal was 3.3V when powered-off, but it's an active low line so that doesn't seem to be it.
Thanks. (will keep this updated)
(I should note that I'm currently in the process of studying electronics, so I've built stuff like voltage regulators, buck converters, so I have a basic understanding of how some of the components work, but it's still very much a WIP (i'm using the Art of Electronics book). I realised that I need to further my understandings at a lower level so I started studying electrodynamics from Morrin Purcell book first. I'm a programmer by trade, but never had a lot to do with electronics before, other than physics competitions).
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