If you find yourself having to set the time and date on your computer every time you boot up, that probably means you've got a dead CMOS battery. Luckily, replacing it is easy. You'll just need a Phillips-head screwdriver.
Step one: power down completely.
you never want any power running through your Toughbook when handling its internal components. Shut it down completely, disconnect the AC adapter, remove the battery, and get static free before starting.
Step two: remove the bottom cover of the laptop.
Lay your CF-19 upside-down. There are 13 screws holding the bottom cover (or base bezel) in place.
Simply remove the screws, open the port covers, and lift the bottom off.
Step three: remove the CMOS battery.
Carfeully disconnect the battery's cable from the board (Marisa shows you where this is located in the video above), then carefully unstick the battery, which will be held with adhesive. Try to leave the adhesive on the board to stick on your replacement battery.
Step four: install the replacement CMOS battery.
Stick the replacement CMOS battery where the old one was and plug it in. Re-attach the base bezel, pop the battery pack back in and you're good to go.