Has it happened to you?
You are in a rush and your iPhone is dying.
You decide to charge your iPhone using a USB cable connected to an alarm clock or your laptop, thinking this is all you need to start charging your cellphone.
You come back an hour later, and your iPhone still not charge, but now is showing a popup warning window on the screen.
You need to unlock to be able to use the usb cable to charge your iPhone. But why?
Why is so problematic to use USB to charge an iPhone.
In this article, I will not only explain why and when this change took place, but also, how to fix it so your iPhone will start charging right away.
And without any warning messages.
When did this happen?
Starting with iOS 12, you will always have to unlock your iPhone or iPad to connect a USB accessory.
This is because of USB Restricted Mode, which protects your iPhone or iPad from hacking tools like GrayKey.
Why You’re Seeing This Message
You’re seeing this message because of USB Restricted Mode, a security feature Apple added in iOS 11.4.1 and improves on in iOS 12.
It prevents any USB devices from establishing a data connection while your iPhone or iPad is locked.
Devices connected to your Lightning port can still charge your iPhone or iPad, they just can’t do anything else until you unlock it.
This protection was installed because hacking software like GrayKey have been exploiting USB connections to crack the PIN protection on iPhones and iPads.
While GrayKey has been used by police departments and other government organizations, it’s possible this same procedure would allow hackers to bypass your PIN and gain access to your iPhone or iPad.
This shouldn’t be realistic.
To deter this exploit, Apple now restricts USB items from starting any sort of data connection while your iPhone or iPad is unlocked.
That’s the default setting, however, you can disable this precaution feature if it gets in your way, but we don’t recommend it.
USB Restricted Mode repels people from obtaining entrance to your iPhone or iPad without permission.
Every time you connect a USB item to your iPhone or iPad while restricted mode is active, you’ll see a USB Accessory notification that says either Unlock iPhone to use accessories or Unlock iPad to use accessories.
iOS 12 Removes the One Hour Grace Period
If you haven’t unlocked your iPhone in over an hour, whenever you plug your iPhone into your computer to charge it, your iPhone will vibrate and bring up the “Unlock iPhone to Use Accessories.”
While this prevents any data-stealing efforts, it also disables charging capabilities.
You can plug your iPhone into a wall outlet and charge no problem, but connecting to a computer will require that you unlock your iPhone, if presented with the message, before it can charge.
In other words, anyone who got their hands on your iPhone or iPad would just have to plug any old USB device into the Lightning port within one hour after you’d last used it to bypass this protection.
Apple added the one hour grace period to make this protection less annoying, but attackers could exploit it.
Even on iOS 11.4.1, putting your iPhone into Emergency SOS mode immediately enables USB Restricted Mode without the one hour timer.
This also disables Touch ID and Face ID until you unlock your phone with your PIN or passphrase.
In the iOS 12 beta, Apple appears to be removing this grace period.
If your iPhone or iPad is locked and you connect a device, you will always be prompted to unlock it.
If USB Restricted Mode is enabled, your iPhone or iPad is always protected.
Now, if you are just miserable having to deal with this security feature (that you might never need), then let’s see how to disable USB Restricted Mode in any iPhone or iPad.
How to Disable USB Restricted Mode
We don’t recommend disabling USB restricted mode.
When connecting a USB accessory, just unlock your phone or iPad, it should be easy and quick with Touch ID or Face ID.
But, if this feature is really annoying you, you can turn it off.
Perhaps you use a lot of USB accessories and you find it annoying to unlock your iPhone or iPad each time.
It’s your decision.
With this new security feature disabled your iPhone will certainly revert to iOS 11.4’s security settings, where it will need to be unlocked to transfer data or charge the device using a data accessory if it hasn’t been unlocked in 7 days.
To disable USB Restricted Mode and let USB accessories function even while your device is locked, head to Settings > Touch ID & Passcode (or Face ID & Passcode).
Then write your PIN to continue.
From the Allow Access When Locked section, enable the USB Accessories selection.
With this solution enabled, devices can link up to your iPhone or iPad while it’s locked.
You can read more about iPhone’s USB Restricted Mode here: https://9to5mac.com/2018/07/09/ios-11-4-1-unlock-iphone-to-use-accessories-explained/
Again, we don’t encourage disabling this feature, but certainly can understand why would you want to do it.
Now you know how to easily charge your iPhone while is unlocked using a USB cable.