Bad Battery?

[garlt4]

96 LT4. Battery is new but won't hold a charge. If I put the charger on it, it only takes a couple minutes to have enough to start the car. While driving, voltage shows about 14 or so. It will restart immediately after shutting down but 2 days later...too low. Also, I noticed that when the battery gets low, the interior/hood lites seem to shut down totally. I assume this is normal. Probably killed a cell in the battery but was wondering if something was drawing that I was unaware of. Any suggestions?

[Edmond]

How about the alternator? It's usually the alternator or the battery and since your battery is new; I would suspect the alternator.

I read that the C4 alternators aren't that good. Mine lasted until 2002 until it pooped. And if it is the alternator; don't be cheap like I was and buy a used unit. Okay, I wasn't cheap; I just didn't have the funds for a new one. Anyway; buy a new Delco one with a warranty.

Generally; I would stick to Delco parts when it comes to electrical items.

[spyysee]

charge the battery then disconnect it. Let it sit idle for a couple days.
Re-connect and start the car. Note the cranking speed (if at all) and the standing voltage.
If the voltage is below 12v, and the cranking is slow, you have a toasted battery.
If not, the alternator is the culprit.

[tnovot]

Originally Posted by garlt4

96 LT4. Battery is new but won't hold a charge. If I put the charger on it, it only takes a couple minutes to have enough to start the car. While driving, voltage shows about 14 or so. It will restart immediately after shutting down but 2 days later...too low. Also, I noticed that when the battery gets low, the interior/hood lites seem to shut down totally. I assume this is normal. Probably killed a cell in the battery but was wondering if something was drawing that I was unaware of. Any suggestions?

If you hook up the charger and the car will start in a couple of minutes, maybe the charger kicks down the charge rate automatically because the battery is full.
You didn't say exactly WHEN you notice the dim lights. If it is while driving, yeh, probably the alternator. If it is while you are trying to start the car, before using the battery charger, maybe the battery is low because of a short somewhere draining the battery. A simple test can determine if there is a battery drain (short) somewhere.

[HPG]

One thing you should never do with a dead battery is to just start the car and depend on the alternator to charge the battery. It's a sure way to burn out the alternator because it runs on full output too long. Completely charge the battery first. Need to do a load test to see if the battery is good Sounds like the alternator may be defective.

Originally Posted by garlt4

96 LT4. Battery is new but won't hold a charge. If I put the charger on it, it only takes a couple minutes to have enough to start the car. While driving, voltage shows about 14 or so. It will restart immediately after shutting down but 2 days later...too low. Also, I noticed that when the battery gets low, the interior/hood lites seem to shut down totally. I assume this is normal. Probably killed a cell in the battery but was wondering if something was drawing that I was unaware of. Any suggestions?

[c4cruiser]

Have a load test run on the battery and have the alternator checked out. Also look for a current draw. You may have something like an open circuit that is drawing the battery down.

14 volts at cruise is about right so the alternator may be working and the battery could have a bad cell. Get everything tested and see where the problem is. The later C4's have decent alternators. The early C4 alternators were easily cooked by underhood heat and they really didn't have a lot of capacity.