Distinguish a prompt from a failure
A request for a passcode does not automatically establish defective Face ID hardware. Ask the owner what operation fails and record any exact warning. Keep the owner in control of authentication rather than collecting a passcode as part of a casual demonstration.
Follow the supported checks
Apple’s guidance covers software, Face ID settings and obstructions around the TrueDepth camera. Use the instructions for the actual model. Check whether a case, protector or visible contamination obstructs the relevant area without assuming every camera arrangement is identical.
Avoid speculative component work
If setup or recognition still fails, document the warning and any prior repair or damage history for service assessment. A working ordinary selfie camera does not by itself validate every Face ID function. Do not advertise a guaranteed repair or use security bypass tools as a diagnostic substitute.
Only one authentication task fails
If ordinary device unlock works but an app does not use Face ID, distinguish app configuration from a general recognition failure. Let the owner check supported settings. Never ask them to disclose credentials merely to make a classroom example easier.
Your practice record
- Failure during setup or recognition
- Warning captured without private content
- Supported obstruction checks completed
- Owner retains authentication control
Sources and further reading
Manufacturer and technical references for the checks discussed in this guide. Follow the instructions for your exact device and equipment.
Repair procedures involve heat, electricity, fragile parts and customer data. Practise under qualified supervision and work only on devices you are authorized to service.