W204
2007 - 2014Mercedes' rescue sheet splits the AMG car by build date: battery in the boot up to 30 November 2009, in the engine bay from 1 December 2009. Once power is back, the 2013 C-Class manual has the owner reset the clock, unless COMAND with navigation does it automatically.
W205
2014 - 2021The rescue sheet for this C-Class marks two possible 12V positions, under the bonnet and in the boot, and the 2018 owner's manual covers cars delivered with a lithium-ion 12V battery as well as conventional ones.
W206
2023 - 2026The C63 S E PERFORMANCE is a plug-in hybrid. A 12V AGM in the engine compartment runs the low-voltage systems, while a 400V lithium-ion pack of 6.1 kWh at the rear feeds the electric drive.