If you can stick with me. I would like to get this worked out.
I have been looking around for a Digital Volt meter that you can plug into the Lighter Jack.
I looked at all the Auto Parts stores in my area within 40 miles. Finally Today, after the loss of Steering on a Steep, Turning, Dirt road, and getting MAD at GM, I stopped a Walmart to get a set of Ramps, to get underneath, to get at the ground connections. I took another look at the rack by the Auto Batteries. Took a second look, right back to the wall. Found one. $15. 16.93 to be exact. Called a Batt Monitor. It is listed on the receipt as 002989205161. This was the last one, way in the back HIDDEN away. This will give you the Number and you might want to order it.
I checked on a Clip-on Current Meter to check on the Currents of the Alternator, and the Starter. Some of the older clerks DID know what I was talking about, even had one in their tool boxes, However they could not help me order one.
I do Know that in my 2010 Cobalt that the Lighter Jack is tied to the battery, Just went out to take a look. 12.6 volts, which went down to `12.5 volts as I opened the door and the roof light came on.
Now if you can get a Battery Maintainer. $25? If you can get one with the Lighter Jack, on it, you could leave it on the seat, plugged in and keep a Trickle Charge on the batter. Next time you go to start the car, Take out the charger, and you should have 12 something volts on the Meter. Try and start the car. You should keep the 12 Volts. It will drop when the engine is turning over. May go down close to 10 Volts.
Caution! If the car is outside! but actually, at anytime you should have the extension cord plugged into a GFI Ground Fault Interrupter. This will help avoid Electrical Shock.
So Far So GOOD?
If you can get a manual for the car, try doing the Basic Maintenance; Check the oil, Coolant, look at the tyres to see that they have some air. You may have a small compressor in the Trunk. If any are low, try to blow them up. Your Battery may not have enough of a charge. Just re-connect the Battery Charger, and tomorrow is another day.
Not to Worry. After 24 hours the battery will have enough charge to try some more testing.
If you get the thing running say so.
I gave my daughter our old Escort. She kept that little book with all the troubles, and the repairs that we made. When she turned the car in, the dealer gave her $500 for that book without Batting an Eye. If there had been a book like this in the Glove Box, think of all the trouble we would be avoiding.
My wife is British.
Your Dutch Uncle Dave.