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.
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.
What causes a car battery to keep dying.
If your alternator has a bad diode your battery can drain.
Let s find out what does it mean and how to fix this problem.
Remember that the drain doesn t have to take your battery to zero overnight just low enough for it to not start.
That seems like a tiny amount but a single incandescent dome light pulls enough power to drain a battery in one day.
Car battery problems specially a parasitic battery drain are difficult to diagnose sometimes.
If the battery drains when the vehicle sits for three or four days that s a lower amp draw than one that drains.
Why does a car need battery.
The simple answer is yes but a car battery can only be drained when it sends more power than receives back from an alternator.
New vehicle models make it specially difficult time consuming and frustrating.