Battery issues
12-10-2007, 06:23 PM
#1
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Battery issues
Hi I recently bought a new battery for my s from interstate, and it seems that after a week of sitting, its very hard to start and when it does it stalls. I cheched the battery with a multimeter and all is well when started it reads about 14.50v and then when the idle comes down about 13.85v. I also checked voltage after a week of sitting in the car it read 12.19v, this seems kind of low, and just wanted to know if anybody knows what the voltage is for these cars when sitting for more then a week.
12-11-2007, 10:42 PM
#4
Well i recently installed a vafc and i leave it on display so i can see the revs and battery. i noticed when i started the car it would show 14.5 volts then as i drove it dropped to 12.8v and it idled really low. So i cleaned the battery terminals and tightened them now it idles between 14.3-14.5 so regardless it should be in the 14 area. hope this helps
12-11-2007, 10:51 PM
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Research battery parasitic drain. What may be happening is that while your car is off something inside may be on, it could be anything from coins in the cigarette liter to the light bulb inside the glove box.
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12-14-2007, 04:30 PM
#8
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Originally Posted by shakes,Dec 14 2007, 05:21 PM
Nothing is on in the car, checked with a test light between neg cable and neg terminal, so I think Its maybe a bad new batt.
12-14-2007, 05:16 PM
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A test light between the negative post and the negative cable isn't a valid test for parasitic drain. You need to use digital multimeter wired in series between the negative cable and the negative post when the car is off. Put the meter in the mA (milli amps) mode and see what it says. Every manufacturer has different tolerances for parasitic drain but generally i think its somewhere around 200mA tops. I am at work now but when i get home i will try to find the exact number. The test light should not light with such a low amperage as 300mA. Or....your battery could be bad.