If your alternator has a bad diode your battery can drain.
Fix car battery drain.
Some of the most common reasons for a car battery to die repeatedly include loose or corroded battery connections persistent electrical drains charging problems constantly demanding more power than the alternator can provide and even extreme weather some of these problems are enough to kill a battery on their own while others are usually coupled.
A car alternator recharges the battery and powers certain electrical systems like lights radio air conditioning and automatic windows.
Remember that the drain doesn t have to take your battery to zero overnight just low enough for it to not start.
Why does a car need battery.
They come with more control modules than previous year models and hundreds more electrical circuits.
In other words car battery drains when it is not charged enough which is a common problem when using powerful amplifiers.
The simple answer is yes but a car battery can only be drained when it sends more power than receives back from an alternator.
The bad alternator diode can cause the circuit to charge even when the engine is shut off and you end up in the morning with a car that won t start.
If the battery drains when the vehicle sits for three or four days that s a lower amp draw than one that drains.
That seems like a tiny amount but a single incandescent dome light pulls enough power to drain a battery in one day.
New vehicle models make it specially difficult time consuming and frustrating.