Along with the function of supplying current to the starter motor when starting the engine battery acts as a smoothing filter and the source of power for the entire vehicle electrical system.
In avtomobilyahTouareg two different versions installed batteries.
Option one battery
Set the battery indicator, banks without traffic jams, under the left front seat.
Option two batteries
Battery indicator, banks without traffic jams, under the left front seat and an optional second battery (no liquid electrolyte) in the trunk compartment in the spare wheel well.