By activating a dormant software lock on their newest iPhones, Apple is effectively announcing a drastic new policy: only Apple batteries can go in iPhones, and only they can install them.
If you replace the battery in the newest iPhones, a message indicating you need to service your battery appears in Settings Battery, next to Battery Health. The “Service” message is normally an indication that the battery is degraded and needs to be replaced. The message still shows up when you put in a brand new battery, however. Here’s the bigger problem: our lab tests confirmed that even when you swap in a genuine Apple battery, the phone will still display the “Service” message.
It’s not a bug; it’s a feature Apple wants. Unless an Apple Genius or an Apple Authorized Service Provider authenticates a battery to the phone, that phone will never show its battery health and always report a vague, ominous problem.