I have a brand new battery that drains overnight. When I charge it for 4 hours it's good for only one other night
My car has an automatic transmission.
It could be that the battery is in need of replacement or that there is a parasitic draw somewhere in the system. The latter happens when something gets left on, either due to human error or because of a problem in one of the circuits. An example of human error is a dome light being left on because someone forgot to turn it off. An example of a circuit problem is a short causing the dome light to stay on. A parasitic draw can be determined by placing an ammeter in line with the negative battery cable. Generally, a draw of more than 30 milliamps on an older vehicle such as yours indicates a problem. A skilled professional, such as one form YourMechanic, will be able to determine while your battery goes dead and repair the problem.
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