Q: Can anybody help please? My son's iphone 4 won't allow me to switch on his wifi, it there an alternate method to switching it on please?

Hello Maccas1979,

Thanks for using the Apple Support Communities!

From your post, I understand that you would like to enable Wi-Fi on your son’s iPhone 4. 

The first article below explains how to set up and join a Wi-Fi network if there are no unexpected issues. 

Connect to Wi-Fi on your iPhone, iPad, or iPod touch - Apple Support

If Wi-Fi on the iPhone will turn on, but won’t connect to a network, I would suggest reading over and working through the steps located in the next article. 

If your iPhone, iPad, or iPod touch won’t connect to a Wi-Fi network - Apple Support

If you are unable to even turn on the Wi-Fi on you son’s iPhone 4, the steps located in the next article may help you resolve the issue. 

If Wi-Fi is grayed out or dim on your iPhone, iPad, or iPod touch - Apple Support

Best!