battery dead.
Thread Starter
4th Gear
Joined: Feb 2005
Posts: 4
Likes: 0
battery dead.
Hello, I am having a problem with my 89 vette.The battery is going dead overnite. The LCD fuse was showing a draw on the battery with key off,(pulled fuse ) and battery stayed up for 2 days but now with the fuse pulled it goes down overnite.Can aynone help.Need to know where to go next.
Thanks
Thanks
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Well, thats not the only circuit in the car that can draw excess current. You need to remove the neg batt cable and connect an ammeter from battery terminal to the cable lug and start pulling fuses one at a time to find out where the leakage current is going. Don't forget that there are some 8 wires that go to the positive batt terminal that have fusible links that need to be disconnected one at a time to see if current is going there. GM says leakage current must not exceed 50 milliamps. My 87 draws 27 ma. Also, check at night for underhood lights, vanity mirror lights, console compartment light, door map lights being left on. Do you have a radar detector, aftermarket alarm, radio, audio amp? Check em.
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
This is the proper way to approach this problem. My 94 draws about the same current just under 30 ma. I had to unplug the hood lights, keep doors closed and first short across ammeter to activate the cars systems and then remove bypass. For some reason the ammeter could not put thru enough current to activate computers and all. (Problem dependent on meter, meter range, current draw and car system). I was aware of the weird situation before I did the test as I had read about it previous. After you are activated and up and running, you have to wait till the computer goes into sleep mode and reduces current to get an accurate reading, about 15-30 seconds.
Of course it is always good to know that your battery is good. It will take several amps to bring the battery down overnight (maybe 5 or so). This much current should be easy to spot using this method with the ammeter. Then you can pull fuses and watch the meter for a drop.
Or....
Have you let the battery sit overnight without it being connected. Then see if you can start in the morning.
