mlammert Posted April 16, 2007 Report Share Posted April 16, 2007 Hi all, I had some issues with the D3 when I first installed it (loose constant wire connection)... After I got everything fixed, I discovered the battery was dead... After jumping the car, everything seemed fine as far as I could tell... I have "tested" the car battery by using a voltmeter between the positive and negative battery terminals... Typical readings after installing the D3 is around 12.3 to 12.5... The car sat overnight and I tested it this morning and it was 12.37... Question: 1) Is this the proper way to test and see if something is draining my battery??? 2) Do these readings that I am getting sound correct??? 3) Since you get 14v while the car is running, is it true that the battery will "level off" to around 12v after the car is off??? Or, is this not true??? Just trying to be sure the dead battery was due to using ACC all day long and having the doors open and all that stuff... And, not due to mis-wire... Thanks, Mark Quote Link to post Share on other sites
scrupul0us Posted April 16, 2007 Report Share Posted April 16, 2007 well u typically get 14V b/c the alternator is charging the battery and as such youll read a higher voltage... with the car off what you've measured seems normal to me... and yes.. forseeably if you had the dome lights on and the radio on for a good period of time u could drain the battery down... but as u tested the next day the battery level was just fine personally i think you are good... FYI the deck has a vehicle diag that will tell you the battery voltage Quote Link to post Share on other sites
cntrylvr79 Posted April 16, 2007 Report Share Posted April 16, 2007 Hi all, I had some issues with the D3 when I first installed it (loose constant wire connection)... After I got everything fixed, I discovered the battery was dead... After jumping the car, everything seemed fine as far as I could tell... I have "tested" the car battery by using a voltmeter between the positive and negative battery terminals... Typical readings after installing the D3 is around 12.3 to 12.5... The car sat overnight and I tested it this morning and it was 12.37... Question: 1) Is this the proper way to test and see if something is draining my battery??? YEs and no. This will verify that your battery is fully charged and there are no dead cells in it. The test for current draw is completely different. 2) Do these readings that I am getting sound correct??? Yup 3) Since you get 14v while the car is running, is it true that the battery will "level off" to around 12v after the car is off??? Or, is this not true??? Yeah it's true. When running the average car's alternator will output between 13.8 and 14.8 volts. When the car is turned off the battery will slowly bleed off the over charge and rest at 12.3 to 12.67 volts. Just trying to be sure the dead battery was due to using ACC all day long and having the doors open and all that stuff... And, not due to mis-wire... I'm going to go with accys being on all day. Thanks,Mark Welcome Batman Quote Link to post Share on other sites
mlammert Posted April 16, 2007 Author Report Share Posted April 16, 2007 Thanks cntrylvr79... I appreciate the detailed and quick response... I agree with you that it was probably the constant use of ACCYS and all that stuff all day long... However, what would be the best/recommended way for me to "test" to be sure something isn't draining the battery??? Just for peace of mind... Thanks again, Mark Quote Link to post Share on other sites
scrupul0us Posted April 16, 2007 Report Share Posted April 16, 2007 check the level daily b4 u start the car Quote Link to post Share on other sites
cntrylvr79 Posted April 16, 2007 Report Share Posted April 16, 2007 It's going to be a bit of work, but first make sure all the doors are closed and nothing is powered on in the car (nothing in cig lighters). Pop the hood. IF you have a light under the hood, remove the bulb. Now you'll need to set the meter to dc current. Next disconnect the positive wire from the battery and rest it somewhere where it can't touch other metal or the battery terminal. Next take a jumper wire and hook that to the positive battery post and the wire you just dicsonnected. Next hook the positive probe of the meter to the battery and then hook the negative probe of the meter to the battery wire. ONce that's done remove the jumper you put in. The meter should read no more than 20 milliamps. If it reads higher than that then there's an excessive draw somewhere. The next step to locate the draw would be to remove fuses from the fuse box one at a time. Checking the meter each time until the draw drops down to an appropriate amount. once you've located the offending circuit, you then must find where that circuit is having a problem. Like I said a current draw test is a little different than a voltage test. Quote Link to post Share on other sites
mlammert Posted April 16, 2007 Author Report Share Posted April 16, 2007 That makes perfect sense... Thanks again for the detailed and informative response... I will do that test when I get home from work... I know the car has a bunch of stuff always on (factory security system and it has dash lights that are always on - weird but true)... So, if you have something drawing current from the battery, will the battery still read 12 volts if you test the battery??? I would assume it would drop below 12 volts... Again thank you very much for the knowledge, Mark Quote Link to post Share on other sites
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