A phone or tablet feature that has completely stopped should be checked for a disabled permission or setting before assuming hardware failure. For iPhone iCloud Photos sync, first check sync status, cloud capacity and a recent photo on iCloud.com or another trusted device.
What this covers
- iPhone iCloud Photos sync with this exact failure state
- Diagnosis across device storage and cloud capacity versus network, power and Apple Account
What it does not cover
Try in this order
0 of 4 completedCapture the exact failure state
ReversibleCheck whether the feature is grayed out, missing from settings entirely, or present but unresponsive when used. Expected behavior: upload and reconcile the same library without losing originals or edits.
Isolate the component boundary
ReversibleCheck sync status, cloud capacity and a recent photo on iCloud.com or another trusted device. Test the same feature in a different app that uses it, and with recently installed apps disabled or in Safe Mode. Boundary to separate: device storage and cloud capacity versus network, power and Apple Account.
Correct only the proven cause
ReversibleConnect power/Wi-Fi, free required space and let sync finish before deleting anything. Re-enable the permission or setting, or update/reinstall the one app where it fails.
Verify and stop safely
ReversibleConfirm the feature works from a cold restart in at least two different apps. Never disable/delete the library until another verified copy exists.
Evidence ledger
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