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google state of charge voltage for a 12 volt automotive battery

engine off.. headlights on for one minute.. then off...

set digital volt meter to 20 volts DC scale..

12.65 volts is a fully charged battery

12.45 volts is a 3/4 charged battery

12.25 volts is a 1/2 charged battery...


if you could start the engine...  and the battery tests above 12.5 volts..

with the engine running..

14.1 to 14.7 volts is expected on most cars...   some are a little higher

this shows the alternator is properly charging the battery..  

ohhhh...okay, got it.  

do dah di dot da dah..   Charge!!!!!  

got the battery back and showed 97% charged but autozone ran a test on the battery and the test said the battery was BAD. Thought id take it home anyway to see if i could still try it. Tried to start car and it did do some extra clicking, can't explain what the extra clicking was, but the car still didn't turn over. I'm guessing the bad battery might or might not be the problem?? All the lights in the car and stuff came on but not turning over.  

measure battery voltage while you are using your remote starter switch to attempt to crank the engine..

does it stay up ...

do the HEADLIGHTS stay bright when you attempt to crank the engine with the headlights on...

do you have any other cars that you could borrow a battery from to try it..

now some more volt meter tests...

set volt meter to 20 volts DC scale..

engine block to negative battery.... while attempting to crank... post voltage you get while attempting to crank..

battery positive post to the starter top post where the battery cable is attached..  

you can use your remote starter button to help you with this one...   if you have a friend to help turn the key...

hook one of the clips of the remote starter button to the post on the starter..  the other clip to your volt meter probe..   the other volt meter probe to the positive battery.. hold down the remote starter button to make the connection to the volt meter.. then have your friend attempt to start the engine... note voltage...  post it..  

Helpful tips.