Porsche: electronic key battery replacement, flat batteries, flat blade

Question
i have a CLK and the battery on one of the electronic keys seems to have died. Could you please provide some guidance. Much appreciated!

Answer
Batteries are easily replaced.  Just use a flat blade screwdriver to pry the key fob open.  Inside you'll find one or two flat batteries, depending on your model year.  The size of the battery will be stamped on its surface.  You should be able to find replacements at your local department or electronics store.