suddenly I can't access my son's iphone on Find my iphone how do I turn this device on

Hey there sportysuee,

Great question, and we'd like to help however we can.

If you've already reviewed the link above your post, Use the Find My app to locate a missing device or item, we also recommend taking a look at this second article. We wanted to call special attention to the 'Stop sharing your location' section here: Find friends and share your location with Find My

After reviewing the details above, and if the same issue remains, what exactly occurs when you try locating his iPhone? The more details you provide, the better equipped we'll be to assist.

Cheers!