new battery still charge every two weeks now, i's dead every night
My car has 114000 miles.
My car has an automatic transmission.
This may be a sign of a failing voltage regulator or a failing alternator. As you may know, the alternator is responsible for charging the battery while the engine runs by generating amperage and recharging the battery while the engine turns the alternator. The voltage regulator is a unit that regulates the charging of the battery by the alternator. Often, this will result in the alternator allowing too much power to be delivered to the battery resulting in damaging wires and prematurely destroying the battery.
In other cases, it may mean the alternator is not supplying enough power to the battery, undercharging the battery or not charging it at all. In either case, I would recommend having an expert, such as one from YourMechanic, come to your location to diagnose your vehicle’s charging system and see if there is some sort of other electrical problem within the car that is causing the dead battery.
Have a car question? Get free advice from our top-rated mechanics.
Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing