In order for Apple devices to be sent to Apple for Repair / Replacement, they must first be disconnected from the iCloud service. To do so:

  1. First make sure your device has been shut down. 
  2. Login with your Apple ID at

  3. Choose "Find iPhone"

  4. From the dropdown  called "All Devices" on the center of the screen, click on the device you have powered down:

  5. Select "Remove from Account"

  6. Confirm the removal of the device.