This article will tell you how to stop your iPhone from going to sleep too quickly. If you want to change your Lock Screen settings to turn off Auto-Lock or change how quickly your screen dims, we'll cover that as well. In addition to "why does my screen turn off so fast?" you may also be wondering, "why is Auto-Lock grayed out on my iPhone?" We'll tell you why this happens, and how to fix it.
Related: How to Write Notes Directly from the Lock Screen on Your iPhone
Jump To:
- What Is Auto-Lock on the iPhone & iPad?
- How to Change Screen Lock Time on Your iPhone & iPad
- How to Fix a Grayed-Out Auto-Lock on Your iPhone
What Is Auto-Lock on the iPhone & iPad?
What is Auto-Lock? Auto-Lock on an iPhone, or Sleep mode, dims the screen after a set amount of time in order to extend iPhone battery life and prevent others from accessing your unlocked iPhone. Auto-Lock activates a screen timeout after a set number of seconds or minutes unless you disable Auto-Lock. In the same way that your computer goes to sleep after a set amount of time, the iPhone, too, will dim the screen so that the battery life is conserved. If you disable Auto-Lock to get rid of your automatic screen lock time, it will cut into your battery life.
I’ve changed my iPad Auto-Lock time most often when cooking with a recipe as I need to easily be able to see the next step without covering my iPad in food. You can change Auto-Lock settings for tasks like this, and then easily change it back when you're done. However, you also have the option to turn off Auto-Lock altogether. If your iPhone keeps shutting off, use the tips below to change your iPhone or iPad's Auto-Lock time. To learn more great iPhone and iPad tips, check out our Tip of the Day newsletter.
Related: How to Find Your iPhone Even If It’s Dead
How to Change Screen Lock Time on Your iPhone & iPad
The most effective way to stop your iPhone from sleeping is to change your iPhone sleep timer. Auto-Lock is an easy feature to change in Settings. You can select 30 seconds all the way to 5 minutes before your screen locks; you can also choose to set Auto-Lock to Never, essentially turning Auto-Lock off. Your iPhone's screen lock time is, by default, set to 30 seconds.
How to Change Auto-Lock (Sleep Mode) on the iPhone & iPad
- Open the Settings app.
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- Tap Display & Brightness.
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- Select Auto-Lock.
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- Set the timer to the time that works best for you.
![auto lock settings]()
If you attempted to change your Auto-Lock time and suddenly panicked because it’s grayed out—take a deep breath and proceed to the next section of this article. Don’t worry; it’s an easy fix.
How to Fix a Grayed-Out Auto-Lock on Your iPhone
Auto-Lock on your iPhone will be grayed out when Low Power Mode is on. Low Power Mode on the iPhone and iPad forces Auto-Lock to remain at thirty seconds to conserve battery life. To stop Auto-Lock from being grayed out, all you need to do is turn Low Power Mode off. If you follow our tip for how to turn on Hey Siri, you can activate Siri and say, “Turn off Low Power Mode.” Or, you can use the tip below to manually turn Low Power Mode off. Once you’ve turned Low Power Mode off, navigate back to the Auto-Lock setting, and you’ll be able to change it to whatever time you prefer.
To fix grayed out Auto-Lock setting and stop your iPhone or iPad from sleeping when you don't want it to:
- You can say, "Hey, Siri, turn off Low Power Mode”.
![hey siri turn off low power mode]()
- Alternately, open the Settings app.
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- Tap Battery.
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- Toggle off Low Power Mode. It will turn Gray once disabled.
![turn off low power mode]()
Now you can navigate back to Auto-Lock in Display & Brightness and change the Auto-Lock time. If interested, you can also learn this nifty shortcut to switch between your open apps on your iPhone.
