What can drain the battery in a car?

+1 vote
asked Apr 5, 2018 in Other-Cars/Transportation by Ares87 (300 points)
What can drain the battery in a car?

What can cause the battery in a car to drain when not driving it?

1 Answer

0 votes
answered Apr 6, 2018 by Oliphant (6,990 points)
First thing I would say is to be sure you left nothing plugged into the cars 12 volt system when the car is shut off.

I've personally done this by leaving a cell phone plugged into my car overnight and the battery drained down and recharging the cars battery fixed it.

Other things that could cause your car battery to drain would be a bad alternator with a short in it, a bad battery with bad cells in the battery and a defective diode in a cars alternator can cause the battery to drain when the cars engine is not running.

When the alternators diode circuit is bad it allows the circuit to continue to charge even when the cars engine is off and this will discharge your battery when you're not driving your car.

I'd take the car to Autozone or another place and have the battery, Alternator and Alternator diode tested to find the actual problem.

103,109 questions

102,465 answers

1,332 comments

7,032,914 users

...