A car can sometimes run without a battery after it’s already started because the alternator supplies power. But the battery also stabilizes voltage, so modern cars can suffer spikes, module damage, or ...

Your car's 12-volt battery is one of its most vital components. It's responsible for sending electricity to the starter motor, which, in turn, sends power to the ignition system and cranks the engine.

You try to turn on your car, and it just won’t start. Maybe the dashboard doesn’t even light up. A likely cause: The 12-volt battery is dead. All cars lose a little battery power when parked. If you ...