How to turn off "Find My iPhone" feature for Apple devices
All iPhones (iOS7 onwards) that get sent in will need to have their activation lock removed. This feature needs to be disabled prior to sending your device in. You can do this directly on your device or remotely on iCloud. This page will guide you through removing your iPhone from your iCloud.
Method 1 – Remove your device from your iPhone or iPad
Turn ON device
Select “Settings”
Select “iCloud”
Click “Delete Account”
Enter your Apple ID password
Select “Turn Off”
Method 2 – Remove your device via iCloud.com
Go to Find My iPhone on iCloud.com. If you don’t see Find My iPhone on iCloud.com, your account just has access to iCloud web-only features.
Click All Devices, then select the [device].
Select cross next to your [device] If the device is offline, the remote erase begins the next time it’s online. You receive an email when the device is erased.
When the device is erased, click Remove from Account. All your content is erased, and someone else can now activate the device.