If its a servicable type of battery (non-sealed) check voltage of each cell and make sure its topped up with distilled water above the metal plates ? For a simple test on a non-sealed battery. With the battery disconnected if you have a multimeter you can keep the postive lead on the positive post and dip the negative probe into the water of each cell being absolutely careful not to touch the metal plates.. Each cell should read a little above 2v, you will have to work out each cells voltage since you will get a accumulative reading in respect to distance from Postive Post where other test lead is. You might find the voltage will dip down when you test cells closer to the positive post, this is where most of the sulfation occurs on the plates closer to Positive side as the battery ages.. The more the voltage dip the more bad the cell, overall affecting battery total voltage. Its common to see the total voltage at around 13.2v after charging then it should slowly go down to 12.6V after resting for a few hours. Each cell should read 2.1V (12.6V) after resting for 100% charge. On the net these voltage correspond to % full, new batteries will tend to read higher. 12.60 V = 100% 12.35 V = 75% 12.10 V = 50% 11.95 V = 25% 11.70 V = 0% You might see individual cell voltages like these (+) 1.85 - 1.98 - 2.1 - 2.1 - 2.1 - 2.1 (-) Total Charge = 12.23 (65% charge roughly) I would give the battery a long charge, check total voltage & individual cell if possible a few hours after charging. Then leave it overnight or a few days checking it again to see how well it holds it charge? Perhaps check again in another week as well.. If it dips down alot you might want to consider getting a new battery. Of course if you have a sealed non-servicable battery forgot the above, just go and grab a new battery since they don't last forever lasting typically 5 years and you dont want to be stuck somewhere The battery on my Z is about 4 or 5 years old.. It starts to have a hard time cranking after 1.5 weeks of no usage while still being connected.. On a brand new battery it still cranks okay with 1 month no usage.. Mind you the Z has a natural minimal drain on the battery as well.. I leave my battery disconnected if its gunna sit there longer than 1.5 weeks.
It's been three weeks since this post, and Saturday morning my battery died completely was replaced. I'm an idiot.
Leaving the door open and the interior light on will drain a battery overnight in my experience. Not good for the light cover either. Just charge it up with a battery charger overnight. If the battery is OK that will do it. If not check for other current drains with a multi-meter.
The guy who replaced my battery did a test, as well as finding the battery was ruined, he found no current leaks. So that was convenient
It's in technical because I thought something I'd done while fiddling with the stereo had drained my battery. At that point the battery had shown no sign of weakness, and it seemed logical to assume that me fiddling with electronics and it dying for the first time were related.
I left my battery connected yesterday and the battery drained in one day . I have half the interior pulled out and front bumper off . So not sure why its draining but I will have another look after everything is together again .
