By November 5, 2006 0 Comments Read More →

Car Battery Drains Overnight

This morning my Corvette was completely dead. The battery is new, replaced mid September. Nothing on the car works, and there is no clicking when I tried to start the car. What could this be.


Hello Lori

Thanks for your email. You really need to have a complete charging system test done to determine what is happening. This test should include the following tests:

1. Load test the battery to check to see if the battery has an internal problem

2. Check the alternator output does the alternator recharge the battery properly

3. Check for a voltage drain is there something left on that is draining the battery overnight like a trunk, glove box or hood light

4. Check and clean the battery cables if the cables are loose or dirty the power from the alternator can t reach the battery

I would bet you either have a Drain something is sucking battery power with the key off. Or you have a bad battery or bad alternator that did not charge the battery the last time you drove the car.

There are a TON of electrical components on that car, so any electrical item that is left on or stuck on, will drain down a new battery over night. I have seen an electric seat motor and an electric antenna motor short circuit and drain a battery down overnight.

Most auto repair shops can do this test for you while you wait, and the cost is probably less than $50. You WANT to test all these components ON the vehicle, so don t take your battery out of the car for testing, take the whole car in for testing. Since this is a Vette .make sure the mechanic is knowledgeable about the charging system of this vehicle.

Austin Davis

About the Author:

Austin Davis, consumer car repair advocate. "Hi there! I love to help people solve their car repair problems and I hope my site was helpful to you today. Thank you for stopping by."