Battery keeps draining

MILEENAVANTINE

MEMBER
2003 JEEP LIBERTY
3.6L
6 CYL
4WD
AUTOMATIC
101,000 MILES

My battery keeps draining if it’s not used for more than a couple hours or more than a day. When I get out of the car, I turn off everything such as radio, ac, plugs. Something is going on electrical and I’ve brought it to a couple mechanics, and nobody has given me an answer, it’s a brand-new battery and alternator. The starter, battery and alternator have all been tested and all came up perfect. I don’t know why the battery keeps draining.

Tuesday, March 1st, 2022 AT 9:37 AM

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

Just to clarify, the battery loses charge if the vehicle is not driven for more than a day, right?

This sounds like the vehicle has an excessive amount of parasitic draw (current drain) on the battery. Every electrical circuit with a battery will have some amount of parasitic draw, but it can become excessive due to any number of faulty electrical components, which will lead to a fast discharge of the battery. For example, this can be due to a glove box light staying on or a shorted switch.

Typical acceptable parasitic draw is around 30 milliamps.

To find out what is causing the drain you will have to use a multimeter and check for the drain on the battery, while removing certain fuses to check if it changes the draw amount.

Here is a helpful video that explains it very well:

https://youtu.be/z5F7WpgjaRs

Also, a good guide on this:

https://www.2carpros.com/articles/car-battery-dead-overnight

Please let me know if you have any questions.
Thank you.

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