By December 9, 20110 Comments Read More →

Why Does My Car Battery Keep Draining Down?

Reader Question

I have a 2003 Infiniti G35 and recently the battery has been dying time and
time again, I took it to the shop and tested the battery and the alternator.
They said both were fine, but while hooked up to the tester it showed the
battery draining while the car was off. Do you think it is possible to have
a weak cell in the battery that still shows as good but could cause it to
continue draining dead? Please help!

Hello there,

You have a “voltage drain” and will need a mechanic to help you track it down.

Some common drains are from

1 Dome lights, glove box, trunk and hood lights that are ON
2. Electric seat motors and power antennas that are stuck in the on position and still running (listen for a humming noise)
3. Radios, cell phone chargers, GPS devices that are faulty

A drain is any electric sensor, relay or device that is ON when it should be OFF and it sucks the electricity out of the battery. Finding the drain can sometimes be time consuming and expensive, so make sure you have a good/qualified mechanic doing this for you.

Austin Davis

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