my iphone cant connect to wifi

Maybe this:

iOS: Wi-Fi or Bluetooth settings grayed out or dim

One user reported that placing the iPod in the freezer fixed the problem.

Also heating sometimes works. See:

Why can't I select my wifi settings?

A trick that works frequently with iPhones:

Settings > AirPlane Mode ON, Do Not Disturb ON

Power down and wait 5-10 minutes

Power up

Settings > AirPlane Mode OFF, Do Not Disturb OFF

If not successful, an appointment at the Genius Bar of an Apple store is usually in order.

Apple Retail Store - Genius Bar

Otherwise maybe this:

Place the iOS device in Recovery Mode and then connect to your computer and restore via iTunes. The iPod will be erased.

iOS: Forgot passcode or device disabled

If recovery mode does not work try DFU mode.

How to put iPod touch / iPhone into DFU mode « Karthik's scribblings

For how to restore:

iTunes: Restoring iOS software

To restore from backup see:

iOS: Back up and restore your iOS device with iCloud or iTunes

If you restore from iCloud backup the apps will be automatically downloaded. If you restore from iTunes backup the apps and music have to be in the iTunes library since synced media like apps and music are not included in the backup of the iOS device that iTunes makes.

You can redownload most iTunes purchases by:

Downloading past purchases from the App Store, iBookstore, and iTunes Store

If problem what happens or does not happen and when in the instructions? When you successfully get the iPod in recovery mode and connect to computer iTunes should say it found an iPod in recovery mode.

Or maybe this

Does the iOS device connect to other networks? If yes that tends to indicate a problem with your network.

Does the iOS device see the network?

Any error messages?

Do other devices now connect?

Did the iOS device connect before?

Try the following to rule out a software problem:

- Reset the iOS device. Nothing will be lost

Reset iOS device: Hold down the On/Off button and the Home button at the same time for at

least ten seconds, until the Apple logo appears.

- Power off and then back on your router

.- Reset network settings: Settings>General>Reset>Reset Network Settings

- iOS: Troubleshooting Wi-Fi networks and connections

- Wi-Fi: Unable to connect to an 802.11n Wi-Fi network

- iOS: Recommended settings for Wi-Fi routers and access points

- Restore from backup. See:

iOS: How to back up

- Restore to factory settings/new iOS device.

If still problem and it does not connect to any networks make an appointment at the Genius Bar of an Apple store since it appears you have a hardware problem.

Apple Retail Store - Genius Bar