Why do car batteries go bad when not used?

That reaction keeps happening, but more slowly, when the battery isn’t being used. That’s why batteries lose their charges as they sit. That’s what the alternator does – it maintains the battery’s charge and it produces extra juice to power the lights, radio and all the other electrical gadgets in the car.

Can a car battery go bad from sitting?

This claim is supported by BatteryModeOn.com, who said the short answer to the question is “a little under two months.” Car batteries usually last for about three to four years—but leaving your car sitting for far too long hastens the decay.

How long will a car battery stay charged when not in use?

If you’re dealing with a fully charged battery that’s relatively new and in perfect condition, it will take 2-3 months for it to lose its power completely. However, you’re probably pushing your luck if you let it sit idle for more than two months.

What happens when a battery is replaced in a car?

When a battery is replaced, in some cars, the battery management system needs to be reset, so it knows that the battery is new.

What causes a car battery to go bad so quickly?

If you start the car and then only drive it about five miles or less, then you are not recharging the battery sufficiently. Such repeated draining of the battery will cause it to go bad pretty quick. I suggest using a battery charge tender to keep the battery charged between uses.

What happens if you don’t reset the battery management system?

When a battery is replaced, in some cars, the battery management system needs to be reset, so it knows that the battery is new. Battery current sensor. If the battery management system is not reset, it might think that the battery is old and weak and some of the electric features will not work correctly.

How do I know when to replace my battery?

Warning signs your car battery might need to be replaced The age of the battery One of the main indicators that you might want to replace your battery is age. On average, your car battery should last five to seven years.