Why does my car battery discharge after shutting down the engine?
Why does my car battery discharge after shutting down the engine? He has certifications in automation and control technology. When you car battery discharges soon after shutting down the engine, it's commonly caused by one of three things: Your battery may have reached the end of its service life (often 4 or 5 years). A parasitic drain is depleting battery power. What should I do if my car battery discharges? If you don't want to buy a memory saver now, you can use a 9V battery instead. Connect the 9V battery to the car battery terminals before disconnecting the cables....