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e550 why does my battery die for no apparent reason? What is draining the battery even though the engine is off and no lights are on?
Hi there - the big question is how long does it take the battery to die?
Most batteries will self-discharge (just sitting) within about 3 months.
Even though your car is sitting with the engine off, and all the lights off, there is a small amount of current flowing to the on board computers, navigation system, alarm system, etc. This is called parasitic draw, and typically the higher-end the car, the greater the parasitic draw.
How long does it take for the battery to go dead?