Battery, Voltage, Ground, Alternator Anomaly

[JS02Vue]

So my 02 Vue, with a 7 month old battery and clean cables, dies as I pull into my parking garage. The voltage dropped enough to reset the clock. I wait 30 seconds, it starts up, I park it. Two hours later I come out and it starts fine. I drive to auto parts store, shut it down, start it up. Drive to Walmart, shut it down, and again, not enough voltage to re-start.

Bought voltage meter, with cables attached volts at 10. Portable jump start box reads 14 volts with car running. My volt meter reads 14. Drive home, back in to parking spot, volts at 14. Shut the car off, volts drop to 10 thru cables. Leave it overnight. Next morning, not enough juice to start. Volts thru cables at 10. Twelve hours later, 2 volts thru cables.

Take cables off and reconnect, only 5 volts making it to the jump post, 6 volts on the cables.

Take cables (very clean) off, getting 12 volts thru terminals. Hook battery up again, 10 volts thru cables and at jump post on fuse box. Unhook positive cable. Checked the engine ground, that is well connected and clean. Followed other ground under the battery box as far as I could reach, wiggled it a little, seems fine. (Not sure but I think this grounds to the body on the right underneath side of the battery box, if so, it is well connected and clean.) Pulled the battery fuse, it is fine, stuck it back in. Reconnected positive to terminal, now the voltage is at 12.2 thru cables and on the jump post. Starts right up. Parked it in garge.

Does anyone have any idea if this is a ground issue, an alternator issue, or just a random anomaly? I had the feeling that something was drawing juice off the battery when it was connected and that is why I was getting such low voltage readings with the cables attached. Could this have been caused by a loose ground or is it a sign the alternator isn't working as well as it should?
02 Vue, 64K, 3k oil changes, new tires, new rear shocks from Napa are 5 star improvement over OEM, battery 7 mo old everstart from Walmart. Thanks all for reading long post and helping out.

[BobbyP]

IMO under the battery box is a bad location for a ground. Especially when the vehicle gets older and acid may make it's way to this area.

[fdryer]

Being new to Saturnfans you may not have read the threads about early AC Delco side terminal batteries that cracked the positive post allowing acid leakage onto the cable destroying the internal wire strands without any exterior evidence. A trip to the dealer and several hunderd dollars later was the result of the battery leakage and corroded cable, both replaced. If you have a side terminal battery you may want to look more closely next to the cable clamp where the insulation covers the wires underneath. Flex the insulation forcefully if you have to in order to expose the wires to see if there is any corrosion under there. A battery that reads only 12v is possibly undercharged from your recent observations and may be slowly killing the battery unless a full charge is done either with an overnight charger or a good long drive as long as the alternator is outputting the proper charging voltage. Battery voltage will be 12.5v whether reading on the battery terminal itself or on the battery cable clamps, engine idling will be 13.7v, and above idle 14.5v (give or take a few tenths of a volt for each measurement) as long as the serpentine belt is taut. Any lower readings may indicate a poorly charged battery needing a full charge or the alternator may be failing.

[BobbyP]

Being new to Saturnfans you may not have read the threads about early AC Delco side terminal batteries that cracked the positive post allowing acid leakage onto the cable destroying the internal wire strands without any exterior evidence.

Interesting... I had the cracked AC Delco side terminal battery about 5 years ago on my SC. The dealer didn't let me know it was a common problem. I didn't have the electrical problem. I cleaned everything up as well as possible. It destroyed the nicely painted finish on the metal parts under it.

[JS02Vue]

Being new to Saturnfans you may not have read the threads about early AC Delco side terminal batteries that cracked the positive post allowing acid leakage onto the cable destroying the internal wire strands without any exterior evidence.
You are correct, I am new to saturnfans and had not located that post about the cracked side terminals, although I did spend many hours looking at battery related posts. And, the battery I replaced was the AC/Delco and it had a cracked terminal that leaked around the postive cable and was nasty. I never thought to check inside the cables. The Vue has started and run every time since I gave a good tug on the ground wires and disconnected and reconnected the cables to the side terminals. I think I will replace the positive cable just to be on the safe side. Thanks for all your help to the newbie!