iPhone 15 suddenly dead and unresponsive: Is it a logic board issue or a known failure pattern?

As a last ditch effort, try using the tip of rubberized paperclip in charging port to see if you have lint buildup in it.

This happened to my son’s iPhone yrs ago. We had tried everything & Apple was unable to diagnose so we bought new phone. Mos later came across video showing how lint build up in charging port can cause this. Using tip of paperclip I pulled out a big chunk of lint. Phone turned on immed & worked perfectly after that.

Anyone putting phone in pockets should place it in upside down w/charging port on top to prevent lint up & periodically use can of air to blow out ports. Good luck 🤞

Silverskates wrote:

As a last ditch effort, try using the tip of rubberized paperclip in charging port to see if you have lint buildup in it.

This happened to my son’s iPhone yrs ago. We had tried everything & Apple was unable to diagnose so we bought new phone. Mos later came across video showing how lint build up in charging port can cause this. Using tip of paperclip I pulled out a big chunk of lint. Phone turned on immed & worked perfectly after that.

Lint buildup can cause the phone to stop charging. However, it's not sudden. It happens gradually, generally with the cord not staying properly connected. Also, it happens far less with the USB-C port than the Lightning port.

While I find it unlikely that the folks at the Apple store didn't check this, it certainly won't do any harm to check again. But I doubt it's the problem.

If it is dead, they cannot do diagnostics.

If they managed diagnostics then it is likely a display failure but that would need to he tried

Either way unless you live in UK or EU you are out of warranty and it will be expensive, between $200 and $500 at a guess

UK and EU warranties are longer

Silverskates wrote:

This happened to my son’s iPhone yrs ago. We had tried everything & Apple was unable to diagnose so we bought new phone. Mos later came across video showing how lint build up in charging port can cause this. Using tip of paperclip I pulled out a big chunk of lint. Phone turned on immed & worked perfectly after that.

...

Years ago? That was maybe a lightning port

NEVER poke anything into a USB-C port, they have a delicate central part. They are not as robust as Lightning whatever Brussels thinks.

A rubber bulb air blower is all that should be used

I visited both an Apple Authorized Service Center and an Apple Store (Genius Bar).

Surprisingly, neither could diagnose the root cause.

Are you saying that neither opened up the phone to check to see if the battery failed, or a connector was loose, etc?

Is it normal for Apple diagnostics to not detect anything at all?

If the phone cannot power on, there is nothing to detect, so yes this would be normal and expected in a case like this.

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