this post was submitted on 19 Jun 2025
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I tried to start my laptop earlier, only for nothing to happen. It won't start on battery or when plugged in (it can run without a battery when plugged in). The battery does seem to be dead, and so is the 3V CMOS battery.

I opened it up and noticed a circle visable on one of the inductors. Hopefully you can see it in the picture.

Could this be the problem, or is that normal?

Update: I've tested some suggestion and watched some repair videos, but I found nothing. Goodbye old friend πŸ₯²πŸ€š

Thanks for the help guys

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[–] [email protected] 14 points 4 days ago* (last edited 4 days ago) (6 children)

That’s normal, inside of the inductor looks like this:

You can also use a multimeter to test across the inductor. It should have no resistance / will beep in continuity mode.

[–] [email protected] 4 points 4 days ago (2 children)

Thanks. I guess I was just hoping it would be an easy find and fix. The beep confirmed hope is lost πŸ₯²

[–] [email protected] 3 points 4 days ago (2 children)
[–] [email protected] 4 points 4 days ago* (last edited 4 days ago)

The beep multimeters make when in continuity mode. It is a way to test that 2 points are electrically connected with little/no resistance. If they are connected the multimeter will emit a continuous beep. If there is no beep than either the points aren't connected or there is a resistor or something else preventing the connection. The amount is resistance required to prevent a connection (measured in ohms) tends to be possible to set on the multimeter.

[–] [email protected] 2 points 4 days ago

Just the continuity test πŸ˜…

[–] [email protected] 2 points 4 days ago (1 children)

Just so you know, as an inductor is just a small coil of copper, the resistivity might be low enough to trigger the beeping on the multimeter! So maybe it's not dead. I've seen a lot of burned down inductor and trust me it looks way worse.

If your multimeter can measure resistance in miliHoms, you should be able to measure at least ~10mR or more (that order of magnitude) Note that measuring a circuit like so is not guaranteed since there's other stuff on a PCB that gets measured at the same time.

Did you remove the motherboard and looked at the other side?

[–] [email protected] 3 points 3 days ago

Ah, I realise my wording was very confusing there. I meant: Because the inductor is NOT the problem - I don't have any idea what the problem is - therefore the LAPTOP is dead (not the inductor)πŸ˜‚

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