The 2005 edition of the Mini Cooper introduced a few streamlining changes to the body of the car, but the interior parts remained mostly the same. The 2005 Mini Cooper uses a battery, placed either in the engine compartment or the boot, to provide electrical power for the auto and accessories. Removing the battery in a 2005 Mini Cooper only requires a few simple tools and can be done by even the newest shadetree mechanic.
Find a flat, even surface with plenty of room in which to work. Shift the Mini Cooper into "Park" and turn off the ignition. Remove the keys.
Insert a computer memory saver into the 9-volt socket on your Mini if you want to save any of the computer or stereo settings.
Locate your battery. In the 2005 Mini Cooper and Mini Cooper convertible, the battery is in the engine compartment, on the driver's side. In the 2005 Mini Cooper S and Mini Cooper Convertible S, the battery is located in the rear boot. To access the battery in this location, first lift out the boot mat.
Remove the battery cover by unsnapping it at the sides.
Loosen the clamp on the negative battery terminal with a wrench. Pull the clamp off the terminal and place it out of the way of the battery.
Loosen the terminal on the positive battery cable. Pull the cable off and tuck it to the side.
Remove the battery from the compartment.