Hi, since my BMW e36 BJ 2003/11 is almost at the end of the Baterie after 1 month of service life and with new lead battery, I would like to install a switch (interruption of the Minus Pole). Which type would you recommend Schlater? Pay attention to wa sist? Is mInus the better choice? Quote: If you install a main switch, you switch the entire vehicle current over it. So the switch has to carry the entire load. A small resistance of 20mOhm, which can form quite quickly if the switch is open for a longer time, can fry up to 3 volts at the start. So the car would not want to start properly with longer service life.