Q: Can disconnecting your car horn cause your car battery to drain over night?

asked by on December 15, 2016

The car battery has been down in the mornings needing a boost. Driving it around the block was helping it to start the next day, but now the battery continues to drain. Two new batteries have been put on the car but the battery is still down the next day.

My car has 151059 miles.
My car has an automatic transmission.

A horn being disconnected will not cause the battery to get drained. The battery being drained or low on charge after sitting should first charge and test the battery then check to see if the vehicle has a draw on the battery. There is a possibility that the alternator is drawing the battery down and should be tested by a mechanic like one from YourMechanic.

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