Reply To: 80% Charge Limit occasionally charges to 100% — normal calibration cycle?
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Alex TannerAn iCloud Keychain/2FA re-key operation (triggered by Passkey rotation or Apple Account security audit) wakes the Secure Enclave for ~90 s every 14 days, pulling 1.2 W sustained; the PMGR treats this as “user-initiated activity” and temporarily lifts the 80% ceiling to guarantee boot-ready capacity. Correlate with log show --predicate 'subsystem == "com.apple.authd" or subsystem == "com.apple.cloudd"' --info | grep -E "keychain.rotate|passkey.sync|2fa.*challenge" — timestamps matching the 100% charges confirm the cause. No hardware fault; mitigate by scheduling “Require Face ID for Passkeys” off-peak or disabling automatic Keychain sync in Settings > Passwords > Password Options.