Follow each step carefully.
Turn off the PlayStation and disconnect all cables and accessories.
Lift the front edge of the lower right cover to release its clips and remove it.
Use a Phillips screwdriver to fully loosen the captive screw on the CMOS battery cover.
Grip the screw on the cover and lift the CMOS battery cover off.
Pry up the CMOS battery gently with a spudger and remove it from its slot.
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