In rare instances, the setting to turn on Wi-Fi on iPhone 4s may appear greyed out or dim. You might see the following when you tap Settings > Wi-Fi.
Follow these steps to resolve the wifi grayed out issue on iPhone 4s in two ways:
These methods also be available to iPhone 5S, iPhone 5, iPhone 4S, iPhone 4, iPad air, iPad mini, iPad 3, iPad 2,new iPad, iPod touch
- Restart your iPhone 4S .
- Make sure that airplane mode is off by tapping Settings > Airplane Mode.
- Reset the network settings by tapping Settings > General > Reset > Reset Network Settings.
This will reset all network settings, including Bluetooth pairing records, Wi-Fi passwords, VPN, and APN settings.
- Make sure that your iPhone is using the latest software. To do so, connect your iPhone to your computer and check for updates in iTunes.
- Go to Settings and turn Airplane Mode and Do Not Disturb ON
- Power down and wait 5-10 minutes
- Power up
- Go to Settings and turn Airplane Mode and Do Not Disturb OFF
If the above two solutions does not help to fix wifi greyed out issues, backup your content and go to Settings > General > Reset > Erase All Content and Settings and then restore from the backup.
If that still does not help, take it to an Apple store genius bar for testing by the technicians.