Why can't I replace my iPhone 15 battery myself?

FYI, the Activation Lock anti-theft feature now covers not just iPhones – but batteries and other key iPhone parts. That might be the source of rumors about parts installation being restricted by iOS 18.

About Activation Lock and Self Service Repair - Apple Support

"If you reuse a battery, display, TrueDepth camera, or Touch ID sensor from an iPhone or iPad that's protected by Activation Lock (the part is still linked to the previous owner's Apple Account), you need to authenticate with the Apple Account used with the previous device to finish the repair.

When using Repair Assistant to finish the repair, you'll be asked to enter the email address or phone number and password that was used to set up the last iPhone or iPad that contained the part. After signing in with the Apple Account, you might have to wait a moment for the process to complete. To unlock the part, follow the onscreen steps.

If you don't configure the part, you'll see Restart and Finish Repair in Settings > General > About > Parts and Service History. The part might not perform as well as a configured part, and features that are critical to safety, security, or privacy might not be available for the part."

"U can change battery cell swapping the BMS, reprogramming and then flashing with 3utools! Did a 12 yesterday and all good! Running iOS 18" from a REDIT user.

Apple is now trying to track battery health of its own batteries as well as third party providers.

That is why you are having issues.

Most consumers will not bother wasting time on this and just have Apple fix it.

Self Service Repair is intended for individuals with the knowledge and experience to repair electronic devices. If you are experienced with the complexities of repairing electronic devices, Self Service Repair provides you with access to genuine Apple parts, tools, and repair manuals to perform your own out-of-warranty repair. Purchase genuine Apple parts and rent or buy professional-grade tools from the Self-Service Repair Store. The online store is operated by a third-party provider ... Self-Service Repair

There is a good chance your friends damaged their phones as well.

I see this with people changing their batteries in their computers.

If they are not careful, a small resistor chip gets knocked off a circuit board and the computer no longer works right.

For a battery replacement, if you really like and want to keep that phone, I would not do replace it. I would have the manufacturer do so. They are too small. The screen can get damaged so easily and then you are going to have an even larger bill to pay to get it to work right. It is just a waste of time like you are doing now. Buy a new phone or change carriers that are giving them away for free.

Apple took away my right to repair my iPhone 15 battery replacement why

Ask Apple. This is a user-to-user site. We are all users here...just like you. Apple is not here.

We can't answer for decisions or policies that have been made by Apple.

Reading this again, I am beginning to think you damaged your phone when trying to repair it or replace the battery - the reason why it shuts off and on.

The software operating system should have nothing to do with the battery.

There are things for security reasons cannot be replaced alone but in pairs - e.g., finger print scanner and processor - if you want the phone to work right.

Usually, if you use a wired charger, it provides sufficient energy to use an iPhone regardless of the battery capacity. Use a charger with a USBC cord plugged into the iPhone 15. Then access the data and back it up to your icloud account. Then maybe you can use the better phone with your saved data in the icloud account.

If you have some sort of water damage, all bets are off.

I am relatively good at electronic repair, but working on an iPhone is another story.

Too much can go wrong by a user trying to repair their own iPhone.

Provide a link if you want and we can read it for ourselves. But it does not make logical sense.