Follow each step carefully.
Shut down your PlayStation and unplug all cables and accessories. Remove any stands supporting your console and lay it down so the right side is facing up.
Firmly pull up the front edge of the larger, lower cover to release the clips.
Use a Phillips screwdriver to fully loosen the captive screw securing the CMOS battery cover (the screw will stay in the cover—don't try to remove it).
Use your fingers to grip the cover's screw and remove the cover.
Use the point of a spudger to gently pry up the CMOS battery. Remove the CMOS battery.
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