Topic: Car Battery Not Charging - Need Help

[hesnotsoharry]

Good Evening,

I have a 2010 Chevrolet Cobalt Coupe that has been having some electrical issues and starting issues. At first I thought it was the alternator, replaced it, and car was good for a while before it wouldn’t start again after a few months. I just replaced the battery thinking maybe the old alternator wore out the battery by not charging it enough and was good for a couple days, and now it won’t start again. Battery shows 12.5-12.6 volts with key in ignition and goes down to 11.7-11.8 when I try to start it and won’t turn over. Terminal connectors look okay in the trunk (where the battery is located). Could it be corrosion or a damaged wire elsewhere? Or something else entirely? Any help would be greatly appreciated. Thanks in advance.

[EV Dan]

I would first check the ground (negative) wire connection from the battery to the body.

Next, charge the battery fully and see if that changes anything.

Last would probably be the starter itself to check.

[bridgecity]

Yes, could be something else. Ignition switch, starter relay, broken wire, etc. In order to diagnose the car needs to be in a no start state while you check voltage along the circuit, that way you can determine where the issue is. Lots of good YouTube videos on how to do that. If you’ve already done the alternator and battery I’d start with checking the chassis ground and starter relay, assuming your battery connections are good. If it’s only happening intermittently, well good luck. Just went through this with a vehicle.