What's the 2012 mercedes e350 auxiliary battery location?

The 2012 Mercedes E350 Bluetec auxiliary battery is located behind the dash in the trim panel. Auxiliary batteries vary in size and specification dependent on the demands placed on it by the vehicle electrical system and can be used as a safety back-up to support the main battery when required or to provide voltage for specific vehicle systems all of the time.You can easily use Your alternator to charge Your auxiliary battery simply by connecting the positive terminals of both batteries. An isolator isolates Your batteries so that Your alternator will only charge Your auxiliary battery when the engine is running, and Your electrical loads won't drain Your starting battery.