How to recover a deeply discharged MacBook Pro after 7 months of storage?

Start by connecting to power and leaving it overnight. It's not operating, you can't damage anything more by trying. Without the processor running, it can only trickle-charge at best.

A deep Reset on a MacBook Pro is to shutdown, let rest for a minute, then start up.

If an overnight (or possibly longer) trickle charge gets the battery back above minimum, then it MIGHT start up, and once it starts up, it can initiate a full Charge Cycle at reasonable levels (like 60 Watts or more).

if you take it to the Genius Bar, without trying to trickle charge, all they can tell you is that the battery is deeply discharged. You already know that.

They MIGHT (or might not) be able to substitute different power and tell you whether it's still alive otherwise.

I suggest you try overnight or longer trickle charging first. You will get more out of your Genius Bar visit, if needed.

Your appointment at the Genius Bar at an Apple-owned Store is free, in warranty or out. Apple Authorized Service Providers may charge an Evaluation Fee, to keep you from consuming their [expensive] technician time with frivolous complaints.

You should get your MacBook Pro diagnosed by Apple, an Apple Store or an Authorised Apple Service Provider next to your place.

Apple - Find Locations

Apple Service and Repair for Mac Laptops - Apple Support

Have a look at the estimated costs, if only the battery has to be replaced:

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copied from: Apple Service and Repair for Mac Laptops - Apple Support

The laptop won't charge if there is the Magsafe LED is not lit. It means there is no power and/or communication with the laptop.

Try wiggling the Magsafe connector a bit since may not always make proper contact on first physical connection. Also, check out the Apple article for troubleshooting Magsafe charging issues:

If your MagSafe cable or power adapter isn't working - Apple Support

You can try using a USB-C charging cable if you cannot get the Magsafe connection working.

Apple laptops have always had issues powering on a laptop when the battery is completely discharged. The laptop may not be able even charge the battery when it gets in this state even if the battery discharge state was only a day. Sometimes a laptop & battery in this state will even prevent the laptop from powering on & booting because the battery is needed on an Apple laptop. You will probably be looking at a hardware repair.

Grant Bennet-Alder wrote:

<< Always been that way even with MagSafe1/2. >.

on Macs with MagSafe 1/2, the System Management [micro]Controller is running that, it does not need the processor to be active to turn on the LEDs.

Apple has not documented this.

Absent clear information, I just posted what I understood to be happening. In Macs with Apple-silicon, most of the SMC work -- powering up and down, and battery and charge management, moved to one processor running at very low speed and low power.

That means without a minimal charge, the processor can't run and the MagSafe light might stay dark.

Your hands-on experience with so many more Macs is probably correct.

Ok, I have an update from the 2023 Apple Silicon Mac I mentioned in my previous post which had no video or signs of life other than just the faintest of heat traces on one or two components on the MLB. I have no idea what state that laptop was in, but it did not seem to have been booting. When I did hold down the power button for 10 seconds to ensure the laptop was powered off, the MagSafe LED did go out & cycle through its colors (not sure if that is normal....forgot to check later on).

I was able to put the laptop into DFU Mode where the MagSafe LED was not lit (prior to initiating a Revive).

After a successful DFU Firmware Revive, the laptop appears to work normally. So I enabled the NVRAM setting to disable the laptop from powering on when connecting the power adapter or opening the clamshell lid.

Prevent a Mac laptop from turning on when opening its lid or connecting to power - Apple Support

When connecting the power adapter with this setting enabled, the laptop did not power on, but the MagSafe LED was lit normally. The Trackpad still has power to it because it still has the haptic feedback where it feels like it clicks which does trigger a power on of the laptop.

I would not expect any OS involvement under these conditions, but very hard to say with these Apple Silicon Macs since they are more complex & mysterious than the Intel Macs. I can only report my actual observations.

<< Always been that way even with MagSafe1/2. >.

on Macs with MagSafe 1/2, the System Management [micro]Controller is running that, it does not need the processor to be active to turn on the LEDs.

Apple has not documented this.

Absent clear information, I just posted what I understood to be happening. In Macs with Apple-silicon, most of the SMC work -- powering up and down, and battery and charge management, moved to one processor running at very low speed and low power.

That means without a minimal charge, the processor can't run and the MagSafe light might stay dark.

Your hands-on experience with so many more Macs is probably correct.

<< The laptop won't charge if there is the Magsafe LED is not lit. >>

I agree that it can not do a Charge Cycle.

But the indicators on the MagSafe end are ONLY lit by commands from the computer, and the computer not running means no MagSafe indicators will be lit up.

Grant Bennet-Alder wrote:

<< The laptop won't charge if there is the Magsafe LED is not lit. >>

I agree that it can not do a Charge Cycle.

But the indicators on the MagSafe end are ONLY lit by commands from the computer, and the computer not running means no MagSafe indicators will be lit up.

AFAIK, if the laptop is off the MagSafe will still be lit Amber or Green. Always been that way even with MagSafe1/2.

I actually have an Apple Silicon Mac that is not booting or "dinging" when power is connected, has no signs of life other than just the faintest of heat emanating from a couple of places on the MLB if left connected to power for a while.....its MagSafe LED is amber.

The negotiation appears to occur with the charging circuitry of the MLB itself.