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What is the voltage from the charger suppose to be?

I have a Macbook air 1466 with liquid damage. The macbook still works but has some malfunctions which I'm trying to fix. I have the schematics for this model and this says that the voltage from the adapter should be 18,5 volts on PP18V5_DCIN_CONN. I have 16,6 volts here and I cannot find a short.

I'm in doubt that the schematic is the final version and want to know for sure that the power rail is really suppose to be 18,5v before I set 18,5v from my power supply on the rail to find the short.

Can somebody confirm that this macbook uses 18,5v and not 16,6v?

Answered! View the answer I have this problem too

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All Macbooks (save the new Retina Macbook which uses a USB-C charging port) use nominally 20V power supplies (the magsafe chargers, 20V will be marked on the bottom of them). In actuality the peak output voltage is under 19V (18.5V as you mentioned is normal), the same as almost all other laptops. However, note that this is peak. The actual supply voltage depends on the draw required (which depends on charge state of battery and workload) and will be either approximately 14.5V, 16.5V or 18.5V. So 16.6V is normal.

Hope that helps!

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Thank you that is helpful. I checked my own retina and that was using 20v like you said, that was somewhat confusing for me.

So bottom line, the board should be able to handle 18,5v, right?

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See the pin out on the Mag-Safe adapter on the right side of this page, sounds like this is not your issue: https://en.wikipedia.org/wiki/MagSafe

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