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Probably measured when warm. Better reball SMC than just reflow. Could need a replacement.
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No, typically GPU will be dead as well as several or all VRAM ICs. Machine might still work on iGPU only though.
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Having ICs in parallel with capacitors can also mess with the readings in unpredictable ways. Capacitors must be measured out of circuit (just rotating them off one pad is fine so that it doesn't fly away).
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OpenBoardView 9.95.1
[URL]https://github.com/OpenBoardView/OpenBoardView/releases/tag/9.95.1[/URL]
Since 9.95.0: Mostly GenCAD fixes.https://OpenBoardView 9.95.1<br /> [... GenCAD fixes.OpenBoardView 9.95.1
[URL]https://github.com/OpenBoardView/OpenBoardView/releases/tag/9.95.1[/URL]
Since 9.95.0: Mostly GenCAD fixes.
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https://[url]https://www.badcaps.net...t1459061[/url][url]https://www.badcaps.net/forum/troubleshooting-hardware-devices-and-electronics-theory/troubleshooting-laptops-tablets-and-mobile-devices/79043-beginner-s-guidelines#post79043[/url]
...
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Not much point wasting time here. CPU will be dead, and in my opinion PCB damage is too extensive to be rebuilt reliably.
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As always, PPBUS_G3H should be measured with the battery disconnected. Charging circuit troubleshooting should be done with battery disconnected first. When the battery is disconnected, this machine should still turn on with a genuine Magsafe2 85W AC adapter, but it probably won't boot fully into macOS.
Battery not being recognized is a good indication that something is wrong either with the battery itself, the SMBUS circuit or the SMC.
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I'd say this is more likely to be the problem. Happens with failing NEC Toking capacitors although I doesn't seem like your board uses one.
But I also had a similar problem on a specific board (I think it was a LA-3551P) where some CPU would be mostly ok, others would crash soon after loading the kernel or other random crashes. A workaround was to add `idle=poll` to the kernel command line which has the effect of preventing the CPU from entering lower power states, which is what looked like was causing the instability. I replaced a few components in the CPU VCore circuit but that didn't...
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U4501 converts eDP from the CPU to LVDS for the panel. If it is not present, the panel should be eDP as it'll be connected directly to the CPU's eDP output.
Connecting a panel with the wrong interface can cause damages.
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Except that this answer is not related to the question that was asked. The answer is about the protection MOSFETs of the BMS, which is the circuit on the battery itself, whereas the question was about the DC-in MOSFET of the charging circuit, which is on the motherboard.
Both circuits have back-to-back MOSFETs, but they do not serve the same purpose.
The DC-in MOSFETs act as an overcurrent protection by switching off the reverse MOSFET when the current flowing through the DC-in current sense resistor is too high.
The DC-in MOSFETs act as an undervoltage protection by switching...
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Crappy multimeters won't understand the fast switching of the MOSFETs, nothing wrong there.
No way iGPU survived getting PPBUS_G3H *then* 3V from lab PSU anyway.
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I like measuring current flowing out of the coin cell first in µA range, it should be a few µA, maybe 16µA max. If it measures higher you know there's indeed too much current being drawn out of the cell and it's generally one of 3 things: bad southbridge, bad SIO (it often has an input to measure the voltage) or leaky dual diode, any liquid damage or dirt (or previous battery leakage, it's very rare with CR2032 but it can still happen) around these can also be the cause. It could also be the capacitor but I haven't seen that yet. After you fix the problem you can measure the current again to...
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10th gen Comet Lake CPU can measure pretty low in resistance to ground (unlike Ice Lake which measures high due to FIVR). However, when the VRM IC dies the CPU never survives on these. Very common problem. People really need to stop buying "gaming" laptops…
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Some BIOSes can switch between AC'97 and HD Audio modes.
It may not be possible to connect line-in though.
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Please stop buying cheap garbage power supplies from Aliexpress, I really doubt it's gonna provide proper 100W USB-PD (and certainly not 240W across all outputs) and you'll be sure to damage some devices at some point.
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That table means "require *at least* the specified power rating".
A 230 W genuine HP AC adapter that has a 100 kΩ high-side resistor should result in around 1.27 V on AD_ID. 0.56 V sounds like it is something like 90 W.
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