How to check yourself whether your iPhone needs a repair

Before heading to the Apple Store with an iPhone for a repair, or before buying a used one, it is worth checking a few things yourself first. The iPhone has built-in tools for this that many people do not know about, and they show exactly where a problem is coming from.

Checking battery health

Go to Settings, Battery, Battery Health & Charging. Here you will find Maximum Capacity: how much battery capacity is left compared to when the device was new. A battery is designed to still have 80 percent of its original capacity after 500 complete charge cycles. If maximum capacity drops below that, Apple itself will show a message recommending a battery replacement. Below that is Peak Performance Capability, which shows whether the device can still deliver enough power to its heavier components without unexpectedly shutting down.

Checking parts and service history

Since iOS 15.2, a Parts and Service History section appears under Settings, General, About, but only if the device has ever been repaired. Here you can see whether the battery, display, camera, or logic board have been replaced, and whether that was done with a genuine Apple part. “Unknown part” means a non-genuine part was used or the part is not working as expected. “Unverified” next to the logic board means it was replaced as part of an earlier repair. For anyone considering a used iPhone, this is one of the fastest ways to see whether the device has already been worked on.

Checking warranty and AppleCare coverage

Through Settings, General, AppleCare & Warranty, you can immediately see whether a device is still under the standard warranty or under AppleCare+, and until when. The same can also be checked without signing in on the device itself, through checkcoverage.apple.com using just the serial number. Handy if you are considering a used iPhone and want to know if it still has warranty left, or to figure out whether a repair through Apple might be free.

Checking signal strength

If you are not sure whether a poor connection is caused by the device itself or by the carrier, Apple’s Field Test Mode can help. Through *3001#12345#* in the Phone app, you can see the exact signal strength in dBm instead of just the bars.

Testing the speaker and microphone

For the speaker and microphone, Apple does not have a dedicated built-in test screen like it does for battery or parts, but a quick manual check works just as well. Open the Voice Memos app, record a few seconds, and play it back to test the microphone. For the speaker, playing a ringtone through Settings, Sounds & Haptics, or simply playing a song in Music or Apple Music, is enough.