How To Drain Car Battery. The only thing that will drain your battery is age temperature and prolonged idleness. Now that we have verified that the battery is experiencing a parasitic draw we can move to exploring the different reasons and parts that can be pulling on your cars battery.
The mission of the alternator is to charge the battery while the car is running. Is something draining your cars battery. Connect the red wire to the 10A20A input port on your multimeter.
Battery drain test.
Dont pay a mechanic. Remove the negative battery cable from the negative battery terminal. Connect the red wire to the 10A20A input port on your multimeter. Just discharge them at about C10 until they do not pass anymore current.
