My iphone 14 pro max turns on by itself while charging.

The iPhone will turn on if it's off, when you plug it in to charge, or if it was turned off after being plugged in to charge, if there's a power interruption and then the power returns.

This is an expected function and by design so you know the iPhone is working correctly. If did not do this, then you would be unable to tell if it was correctly charging in the event it was not turning on to begin with.

There is really absolutely no reason to turn off the iPhone entirely while charging. You can leave it just locked and asleep. If you want to prevent any sounds or notifications from going off, you can use Do Not disturb mode.

click here ➜ Use Do Not Disturb with Focus on your iPhone or iPad - Apple Support

The iPhone would always power up if shut off when connected to a charger; it has never had the ability to charge when “powered off.”

If the battery falls below the level for the phone to be able to operate, it will boot and show the low battery icon until it has power to boot fully:

Charge the iPhone battery - Apple Support

was attempting to address this comment… “There's no reason to turn it off while charging.”

There are various reasons anyone would need their phone turned off during a charge cycle.

Phil0124 wrote:

It will turn on again if there is an interruption in the power flow. If there's an issue with your cable or the outlet used and the power cuts off, the moment it comes back on, it will turn on.

It's designed to turn on when it detects power. Leave it on. There's no reason to turn it off while charging.

chip292 wrote:

For starters, it finishes nearly twice as fast, reducing degrading ‘battery health’ as charging always does anyway.

Actually, it is not reducing degrading 'battery health', it's making it worse because it's bypassing the protections provided by the OS that prevent overcharging and monitoring the temperature while charging.

Second it used to be recommended. This does seem to be something that came about since an update within the last 6mo - 1year. Certain to be other reasons just as important as syncing is to it’s own rights.

Nope. It was NEVER, EVER "recommended". Not by Apple or anyone who knew anything about it.

Starting with the very first iPhone released in 2007, 16 years ago, the phone will automatically power on when connected to an external power source. This is not something that came about in the last 6 months to a year. It's been this way for 16 years.

iPhone does not and has never worked that way.

Every model has always powered up when connected to a charger.

KBeat wrote:

Sure... because of how obscenely hot iPhones have become during charging. From iPhone 12 and beyond, iOS16 - iOS17, it can be extreme and it's a significant change from earlier model behavior.

If your phone is becoming so hot when charging that you think you have to turn it off, you have a problem that should be addressed by Apple.

If, on the other hand, what you're seeing is the notification that the phone is going to pause charging until it cools, that doesn't mean the phone is overheating. It means Optimized Charging is doing what it's supposed to be doing. That is a fairly new notification (for behavior that has existed since Optimized Charging was introduced) and it has confused a lot of people.

Since every single help article a user might encounter when trying to solve the heat issue lands on "close apps, shut down phone", it's entirely sensible users might think to turn it off, let it charge, then use it before it melts through their floors and lands on the neighbor's like Alien acid!

Again, if your phone is getting that hot, charging it while it's off may not even be safe. You have a hardware issue.

Hello! iPhone is supposed to do that.

Take care.

It will turn on again if there is an interruption in the power flow. If there's an issue with your cable or the outlet used and the power cuts off, the moment it comes back on, it will turn on.

It's designed to turn on when it detects power. Leave it on. There's no reason to turn it off while charging.

chip292 wrote:

The important thing at this point to read the original post which states and is restated: ‘ I hook up the charger, turn the phone off and then it starts up again. I would then shut it off again and it starts again’. The fact is, this has changed in recent months and was never the case in the history of the iPhone.

No. It hasn’t changed. That’s the way it’s always worked.

Your phone will remain off unless you plug it in, at which time it will power on and begin charging if it is working properly.

It sounds like you may have debris in your charging port or another issue.

If your iPhone or iPod touch won't charge - Apple Support

Correct. And, if they want the phone to stay off, they should not connect the power adapter to the phone.

For starters, it finishes nearly twice as fast, reducing degrading ‘battery health’ as charging always does anyway. Second it used to be recommended. This does seem to be something that came about since an update within the last 6mo - 1year. Certain to be other reasons just as important as syncing is to it’s own rights.

The important thing at this point to read the original post which states and is restated: ‘ I hook up the charger, turn the phone off and then it starts up again. I would then shut it off again and it starts again’. The fact is, this has changed in recent months and was never the case in the history of the iPhone.

kimfromclayton wrote:

No reasons needed by anyone. If someone wants to turn off their phone and have it stay off, that is their prerogative.

Go ahead. You can turn it off. It will stay off unless you power it on or plug it into a power source.