iPhone Dim on Full Brightness? [Top 6 Reasons & Solutions]

Why is my iPhone dim on full brightness? Don’t worry! This post will tell you why this issue happens and how to fix the issue of the iPhone dim on full brightness.

May by May Updated November 22, 2023
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Why is my screen dim on full brightness?

Sometimes my iPhone screen will dim for no reason although I have it set at full brightness. The setting shows full brightness but the screen suddenly dims. Used to happen in iOS 12.3 and still happens in 12.4.

- Question from Apple Community

A frequent complaint from users is: Why is my iPhone dim on full brightness? Usually, this happens for logical reasons stemming from auto-brightness, original color display, night shifts, and power-saving features. However, it is important to consider potential hardware complications, especially overheating, as they can lead to dimming even when the brightness is set to maximum. Luckily, this post will explore the reasons behind this auto-dimming and find solutions to prevent this issue from happening.

iPhone Dim on Full Brightness

# 1. Auto-Brightness

A common culprit in the spontaneous dimming of the screen on your iPhone is the Auto-Brightness feature. It works in tandem with the ambient light sensor near the front-facing camera to dynamically adjust the screen’s brightness based on the surrounding light conditions. The Auto-Brightness feature is enabled by default, so you should disable it following the steps:

Navigate to Settings > Accessibility > Display and Text Size, scroll to the bottom, and turn off Auto Brightness to control screen brightness settings.

Disable Auto-Brightness

# 2. Low Power Mode

Why is my iPhone so dim on full brightness? Low Power Mode on the iPhone is a configuration designed to reduce background activity and extend the battery life of the device, thus affecting tasks ranging from email retrieval to adjustments to visual elements such as auto-lock and screen brightness. To disable Low Power Mode, go to Settings > Battery and turn Low Power Mode off and on.

Disable Low Power Mode

# 3. Auto-Lock

Why does my iPhone get dim on full brightness? Another potential contributor to the occasional dimming of the iPhone screen is the Auto-Lock feature. This feature is designed to automatically lock the device after a predetermined period of inactivity, usually around 30 seconds, as a security measure to block unauthorized access. As a result, if you find that the screen dims too often, you can go to iPhone’s Settings > Display & Brightness > Auto-Lock to modify the duration as you prefer.

Disable Auto-Lock

It’s worth noting that extending the Auto-Lock duration may prevent your iPhone screen from dimming but this adjustment may cause increased battery consumption.

# 4. Attention Aware Features

Apple utilizes the Face ID sensor to incorporate Attention Aware Features on iPhone, which dynamically adjusts the brightness of the screen based on what you’re looking at. The collaboration between Auto-Lock and Attention Aware is critical. If you look directly at the screen,Attention Aware Features recognizes this and prevents iPhone from locking, even after a specified amount of time.

Disabling this feature may cause the screen to darken unexpectedly in anticipation of an impending self-lock, even if you are actively looking at it. To correct this issue, navigate to Settings > Facial IDs & Passcodes > Attention Aware Features to enable the setting.

Enable Attention Aware Features

# 5. Over-Heating

Why does brightness on iPhone keep dimming? When your iPhone exceeds the safe temperature range, it displays a black screen and a message that says, “iPhone needs to cool down before you can use it.” In response, your iPhone initiates temperature-reducing actions, such as minimizing battery and RAM usage. This, in turn, can lead to an automatic dimming of the screen and a decrease in the overall performance of the iPhone. In this case, you should put down your iPhone and cool it down.

# 6. Hardware Problems

Even after trying various solutions, you still still experience a persistent problem with the iPhone screen dimming. There may be an underlying hardware issue with your iPhone. As a last ditch effort, consider the following ways:

  • Restart your iPhone, as this may reset certain features and resolve some iPhone issues such as iPhone screen freezing, iPhone dim on full brightness, etc..
  • If the problem persists, restore your iPhone to full factory settings.

If these ways do not work, you should contact Apple Support immediately or visit your nearest Apple Retail Store or Authorized Service Center.

Bonus: Safe Way to Backup Your iPhone Without Data Loss

Your iPhone contains tons of files, from videos and photos to important files. If you need to restore your iPhone to full factory settings, it’s important to protect your iPhone data to minimize the risk of accidental data loss.

FoneTool is a powerful iOS backup and transfer tool known for its professionalism and effectiveness. With an intuitive interface, it enables you to back up your iPhone to a variety of devices (including your iPad, iPhones, PCs, or external hard drives). Below is a step-by-step guide on how to make a full iPhone backup of your iPhone via FoneTool:

Step 1: Begin by downloading and installing FoneTool on your PC > Connect your iPhone to your PC using a USB cable.

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Step 2: Launch FoneTool on your PC > Navigate to the left pane and select Phone Backup > Under Full Backup, click Get Started to kickstart the process.

Full Backup

Step 3: Enable Backup Encryption to encrypt backup for iPhone > Specify the backup storage path by clicking Backup Storage Path > Click the Start Backup button.

Start Backup

The Bottom Line

These are the reasons and solutions to “why is my iPhone dim on full brightness”. If you are facing this issue, you can try these solutions one by one to fix this issue. In addition, it’s essential to develop a good habit of backing up your iPhone to avoid data loss. FoneTool is indeed a good iPhone backup tool to help you make an iPhone complete backup and restore to new iPhone. Try it out!

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