damronjr

Yeah, so the last time it happened I was sitting in the car for about an hour with the radio on, IPOD plugged in, and cell phone plugged in, while I was waiting to go into work. No surprise, I actually thought to myself before I went into work, "I wonder if my battery would die from letting it sit that long with everything plugged in like that?" lol This time, I let it sit and idle for a while (about half an hour) as I was listening to the radio, had the IPOD plugged in, and the heater on. After the first half hour I turned it off and immediately unplugged the IPOD, but left the radio on (BTW, all lights off, cell phone was not plugged in, etc...) for less than another half hour, and when I locked it I could swear it sounded weak when the locks came down, but thought nothing of it. When I got out there 9hrs later it was dead. Now, I'm sure this plays into it, but my commute to work is less than a mile, seriously, yes I drive, lol, but it is literally less than a mile, as in my ODO sometimes doesn't even change. I'm thinking that the fact it is street driving and the RPMs don't get very high for very long might play into it. Either way, it is really getting on my nerves and I'm sure my supervisor is getting sick of driving over to where I park to jump my car. I wouldn't drive at all, but I live in the ghetto, I leave for work at 5am, and I have exactly 30min from the time I get off of work ( I work on a shipyard mind you, so it's not out the door and into the car, it's get off the ship, out of the yard, walk 1/2 a mile to my car, get in, and drive another mile or 2 also on city streets) to pick my son up from school.

TkHHR

I am sure everyone has an opinion on this, but here is mine. Once a car battery is down 25% or more in its charge the alternator is not capable of recharging it to a full charge. Jumping it and driving off is not going to help you much. I would have it charged up with a battery charger, then if it goes dead again I would replace the battery or have it done by the dealer if it is under warranty.

09 Panel

So when the battery is dead you jump start the car and just drive it?? Do you ever charge the battery?? The HHR has a small battery that is most likely a AGM style., This means you need to fully recharge it since just driving it isn't going to do the job for you, especially if you only drive a mile to work. Then you will need to learn a little battery management since your not driving enough to make up for the massive load you are putting on it by idling it and running all that electrical load.

BTW, charging a AGM battery properly means charging it at 1-2 amps for 24-48 hours.

urbexHHR

I agree with your theory about it not getting charged from your short commute. That alone wouldn't do it, but I think with sitting in it with the radio on for so long would. Even idling isn't enough to charge it, so that's the same as it just sitting there with just the battery on.

damronjr

Yeah, all this is exactly what I figured. I do own a battery charger, so I guess on Sat I will have to charge it up and go from there. I thought driving it would charge, but like I said, it is a short commute which doesn't even include any freeway driving to get the rpms up. I guess at this point it would appear it never fully charged from the first time it died (which was actually at a tint shop, they left the doors open and interior lights on and whatnot), and the lack of driving it too far or too much probably hasn't done enough to charge it properly. Oh well, I guess I will charge it this weekend and if it dies again off to the dealer it goes!

HipHotRod

From my experience, an alternator keeps a charged battery at 12 volts. Not bring a low one up to charge.

kornellred

A battery in parallel with an alternator will charge up to the alternator voltage output if none of the cells are shorted. How long it stays that way will depend on the condition of the electrolyte. These days automotive batteries are typically maintenance-free, but their ability to hold a full charge will still inevitably deteriorate over time - the Second Law of Thermodynamics and all that stuff, you know. A battery that will not hold a charge is defective.
ChevyMgr recently posted some information that I was not aware of - the alternator output can be electronically controlled (probably by the BCM, switching the output through a network of attenuating resistors). Battery technology is very sophisticated these days, but I am pretty sure that an alternator can fully charge a dischargted battery that is in reasonably good physical condition.

Snoopy

It's not an AGM, it's a "normal" wet cell.

urbexHHR

You know, it's nice that the HHR has the battery run down protection, but the lights stay on for 20 minutes! Isn't that a little much? I mean, my Lumina has that, and they only stay on for about 5 minutes....

damronjr

Battery run down my @$$, if it won't start where is the protection?!?