Reply To: 80% Charge Limit occasionally charges to 100% — normal calibration cycle?
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Owen ParkerThe 80% limit is enforced by the power management firmware (PMGR) but a liquid-detection event in the Lightning/USB-C port forces a safety override that disables charge limiting until the next full reboot — check log show --predicate 'subsystem == "com.apple.iokit.power"' --info | grep -i "liquid|wet" for kIOLiquidDetectionEvent entries correlating with the 100% nights. A stuck eSIM modem reset (common on iPhone 16 baseband firmware 2.0.x) can also spike thermals past 42 °C, triggering the same override; verify with pmset -g thermlog | awk '/ThermalLevel/ && $NF >= 3'. Hardware recovery: force-restart (Vol+ Vol- Side) to clear the PMGR fault latch, then re-enable Optimized Battery Charging to reset the calibration schedule.