There are no instructions or even mention of the 12V battery or its location in the Ford C-Max Energi owner's manual and I couldn't find any photos or video on how to replace the 12V battery in this car, so I made this video. I didn't start recording until I had taken the battery out so I had to make it in reverse, I apologize if that is confusing.

I followed the instructions from this post I found online: http://fordcmaxenergiforum.com/topic/...

Things you need:

Socket wrench
8mm socket
10mm socket
T25 Torx bit w/ driver
Gloves

Nice to have:
Extension for socket wrench
10mm battery terminal ratchet wrench (because space is tight)
10mm deep socket

New 67R-DL battery. I got mine from O’Reilly's Auto Parts for $141 + core charge.

The original battery that needed replacing lasted for three years.