Something is draining my car battery when the car is off.
I would look inside the car for an interior light that is coming on first. Usually a glove box light or a trunk light that is staying on when the car is off. If it’s not a light then a technician can come perform a parasitic drain test on the car where they connect an amp meter to the battery and remove fuses until the drain stops. Sometimes wires going to the trunk or doors can short out causing a drain.
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