Why does the battery on a 2000 Dodge Dakota keep running down if it sits for a long time?

Answer 1

This is a problem common to most, if not all, modern vehicles, and is more noticeable and happens more quickly to older batteries. The problem is typically caused by the engine computer's constant use (and need) of power. Your stereo often uses a small constant amount of power as well, to maintain memory presets and correct time on its clock.

One way to counteract this is to either, disconnect the battery when the vehicle is not to be used for long periods of time (not necessarily the best option, since battery disuse for long periods can be harmful to the battery as well), or make use of a battery maintainer or similar device.

The better option, in my opinion, is to use a solar powered battery maintainer (mine cost about $50 CDN online), which is simply a small solar panel which, when wired properly to the battery or plugged into your constant power socket inside the cabin, sends a small trickle of power to the battery to counteract the draw of power from the vehicle's various electronics, and which also maintains the battery's ability to charge and discharge properly while the battery is not in use. *Important: Be certain to use a maintainer that incorporates technology that prevents battery overcharging which will damage the battery. Not all maintainers use it.*

Battery maintainers that plug into your household outlets are also available, as are battery conditioners which are reputed to recondition your older battery allowing it to perform at near-new capacity.

Also, while replacing your older battery with a new one will not solve the problem, a new battery will perhaps hold a charge for longer periods of time.