To access the SIM PIN settings, go to:

1. iPhone: Go to Settings > Phone > SIM PIN from the Home screen.
2. Tap Settings > Cellular > SIM PIN on the iPad's Home screen.
3. Slide the SIM PIN slider to the ON position (if necessary).
4. Change the PIN by tapping on it.
5. Please enter your current PIN (default is 1234).
6. Make a new PIN.
7. To confirm, enter the new PIN once more.
8. Save the file.

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