This looks like an Acer Predator / PredatorSense limitation, and the short answer is: you usually can’t turn off the 40% battery lock because it is built in to protect the battery and control performance modes when unplugged or under low charge.

What it means

On some Predator models, mode switching stays locked until the laptop is plugged in and above 40% battery.

Users reporting this on Acer’s community say the behavior is normal, not a fault in the app.

What you can do

  • Charge the laptop to over 40% before trying to switch modes.
  • Keep the AC adapter connected when using Performance or Turbo modes.
  • Update PredatorSense and the system BIOS, since Acer support threads often mention software/firmware as part of troubleshooting around battery and performance behavior.

What usually won’t work

  • There is generally no official setting to disable that 40% threshold.
  • Resetting Windows power plans may help other battery issues, but it does not appear to remove the PredatorSense lock itself.

Practical workaround

If your goal is higher performance below 40%, the realistic workaround is to plug in the charger and wait until the battery rises above the threshold, then switch modes.

If it still stays locked even when plugged in and above 40%, that points more toward a PredatorSense, BIOS, or EC issue than a normal battery rule.

TL;DR

The 40% mode lock is usually by design , not something you can simply turn off in PredatorSense.