This is the most common free method for older Toughbook versions. While Panasonic has made this harder on newer Mk series, it remains a standard first step for troubleshooting.
: Plug the CMOS battery back in, reassemble, and check if you can enter the BIOS (press F2 at the Panasonic logo). Method 2: Shorting the Reset Pins (Jumper Method) panasonic cf53 bios password reset free
Some Toughbook motherboards feature specific pads or pins designed to reset the BIOS settings when shorted. Panasonic CF-ALEPEMA5 BIOS LOCKED !! - We'll Fix It !! This is the most common free method for