If the above methods fail, your CF53's password is stored in the Embedded Controller (EC) or KBC (Keyboard Controller) chip, not the CMOS. Removing the battery will not erase it.
For the technically brave, you can perform a Panasonic CF53 BIOS password reset free by re-flashing the EC firmware. panasonic cf53 bios password reset free
What you need:
The process:
Warning: A failed flash can brick your motherboard. Do not interrupt power. If the above methods fail, your CF53's password
The most straightforward and safe method to reset a BIOS password is to contact Panasonic's official support. They can guide you through the process, which might involve proof of ownership and could potentially replace the BIOS chip or provide a reset procedure. The process:
On older CF53 motherboards (check your model under the RAM cover), there is a specific solder pad or jumper labeled PS550 or CMOS_RST.