Setting up a screen lock on an iPhone basically is an attempt by the owner to prevent unauthorized access to the phone. If you set up the auto-lock feature, your iPhone will automatically get locked when it's not used for some time. But when auto-lock does not work, your iPhone screen won't automatically turn off until you make it. Just like the above situation.

iPhone auto-lock does not work

This is serious. But no worries, we are going to show you how to fix iPhone auto-lock not working on iOS 16 and fix the problem.

6 Tips to Fix iPhone Auto-Lock Not Working on iOS14/15/16

This auto-lock problem has not been completely solved by Apple. But here are some tips you can try to fix the issue. They are not 100% working but why not have a try if there is a chance of success.

Fix 1: Re-enable Auto Lock on iPhone

To make sure your iPhone apply the auto-lock setting, it's suggested to re-enable it.

On your iPhone, go to Settings > Display & Brightness > Auto-Lock. Select the timer you want to set for your iPhone.

Auto Lock on iPhone
The selection for Never means that your iPhone will never be screen locked.

Fix 2: Turn Off AssistiveTouch

The AssistiveTouch feature on any iOS devices often causes issues with other features. Auto-lock is not working on iOS 14/15/16 it could be the AssistiveTouch is enabled on your iPhone. So turn off this feature and your iPhone auto-lock should start working.

On your iPhone, open Settings > General > Accessibility > AssistiveTouch and then disable it.

Turn Off AssistiveTouch

Fix 3: Disable Low Power Mode

iOS auto-lock not working on iOS 14/15/16 may due to the enabling of Low Power Mode. This mode prevents many functions from fully functioning on your iPhone. Disabling this mode should fix this issue for you.

On your iPhone, go to Settings > Battery. You will see Low Power Mode there. Switch it to left and it will be turned off.

Disable Low Power Mode

Fix 4: Force Restart iPhone

Sometimes, your iPhone may just need a force restart to fix issues. It's easy, quick and fixes a lot of issues including the auto-lock not working. Different iPhone models have different ways to force restart iPhone:

    • For iPhone 8 and later: Press and quickly release the top Volume button, press and quickly release the below Volume button, then press and hold the right Side button until the Apple logo appears.
Force Restart iPhone x
    • For iPhone 7/7 Plus: Keep pressing the Side and Volume down buttons simultaneously until the Apple logo appears.
Force Restart iPhone 7
  • On iPhone 6s and earlier: Keep pressing the Side and Home buttons at the same time until you see the Apple logo.
Force Restart iPhone 6

Fix 5: Re-activate Passcode Request

Sometimes, you may just need to re-activate your iPhone passcode and the auto-lock would start working.

Go to Settings > Touch ID & Passcode (or Face ID & Passcode) and enter your iPhone passcode. Tap on Turn Passcode Off and then restart your device. Once it is back on, turn the Passcode feature on once again.

Re-activate Passcode

Fix 6: Reset All Settings

Incorrectly configured settings are always the main cause of some issues and this may be the reason why your iOS auto-lock is not working. Therefore, it's suggested to reset all the settings to factory default.

On your iPhone, go to Settings > General > Reset > Reset All Settings. You will be required to enter your iPhone passcode to get started.

Reset All Settings
You should make a backup before resetting all settings. As this will erase all data on your iPhone.
You can create a backup with iTunes. If your computer has installed iTunes, connect you r iPhone to computer. Unlock your iPhone to trust the connection. Then click the small phone icon > Summary > Back Up Now. iTunes will start to make a backup. Just wait until it completes.

back up with itunes

What If Auto-Lock Setting on iPhone Greyed out? How to Fix

Sometimes the auto-lock function on your iPhone might be greyed out and you cannot change the settings because it is stuck on thirty seconds. If this feature is greyed out, it means you cannot make any changes to the settings. The reason for this problem could be that your iPhone is in Low Power Mode which restricts the auto-lock to only 30 seconds. This happens automatically in order to conserve power.

Once you have recharged your device you can disable the Low Power Mode and the auto-lock setting will also be enabled. To enable or disable the Low Power Mode simply go to Settings > Battery > and then toggle the Lower Power Mode switch.

Disable Low Power Mode

If you are experiencing iPhone auto-lock problems on iOS 14/15/16, you can use the above methods to fix it. We believe these tips will help you out.

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