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Old 11-11-2017, 06:28 PM   #1
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Twice now, my recently purchased weekend only 06 GT would not start. Twice I connected my Minnekota battery charger and let it charge for a few hours and the car started and ran just fine. I never had a car that I only drove on the weekend so I don't know if this is normal for the battery to be dead after a week. Probably not. The guy that sold me the car said the battery was almost new and he rarely drove the car and had to jump it each time he drove it which was only every couple months or so. (He only put 3K miles on the car during the 5 years he owned it).

So to check the alternator, I did a little research. Purchased a 7 function digital multi meter, set it to 20 DCV, started the car, touch the black lead to the negative terminal and the red to the positive (red) battery post. Got a spark, the leads got hot, and the digital readout stayed at zero. Was looking get around 14 volts. Either I did something wrong or I have an electric problem, or both.

Is it normal for a car to not start after only a week of sitting? I don't think so. The temperature here has been in the 60s and 70s so it's not freezing. Also, what am I doing wrong with my first attempt at using a multi meter?

I have very little understanding of the basic of electricity, don't persecute me, but I need advice.
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Old 11-11-2017, 08:47 PM   #2
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Twice now, my recently purchased weekend only 06 GT would not start. Twice I connected my Minnekota battery charger and let it charge for a few hours and the car started and ran just fine. I never had a car that I only drove on the weekend so I don't know if this is normal for the battery to be dead after a week. Probably not. The guy that sold me the car said the battery was almost new and he rarely drove the car and had to jump it each time he drove it which was only every couple months or so. (He only put 3K miles on the car during the 5 years he owned it).

So to check the alternator, I did a little research. Purchased a 7 function digital multi meter, set it to 20 DCV, started the car, touch the black lead to the negative terminal and the red to the positive (red) battery post. Got a spark, the leads got hot, and the digital readout stayed at zero. Was looking get around 14 volts. Either I did something wrong or I have an electric problem, or both.

Is it normal for a car to not start after only a week of sitting? I don't think so. The temperature here has been in the 60s and 70s so it's not freezing. Also, what am I doing wrong with my first attempt at using a multi meter?

I have very little understanding of the basic of electricity, don't persecute me, but I need advice.
If you mean you saw a spark when you touched DVM leads to the battery terminals, something is obviously whacko. Check that the battery terminals are tightly connected. Do that after removing one slowly, and seeing if you get a spark. If you do, there is likely a minor short circuit somewhere draining the battery while the car is sitting.

Are you certain you did not have the DVM set to read Amperes? Try it on a flashlight battery. If it does not read, you likely blew the fuse in the DVM.
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Old 11-12-2017, 02:42 AM   #3
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My cd player & aftermarket alarm were draining my battery,
so, got a new battery that was no good...
& it split into pieces in the cold...

then another new battery...

had to pull the radio fuse & disconnect the alarm
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Old 11-12-2017, 08:29 AM   #4
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If you mean you saw a spark when you touched DVM leads to the battery terminals, something is obviously whacko. Check that the battery terminals are tightly connected. Do that after removing one slowly, and seeing if you get a spark. If you do, there is likely a minor short circuit somewhere draining the battery while the car is sitting.

Are you certain you did not have the DVM set to read Amperes? Try it on a flashlight battery. If it does not read, you likely blew the fuse in the DVM.
imp
Thanks for the suggestion IMP. Turns out, I had the leads plugged into the wrong holes on the multi-meter. I had it set up for DC Current Measurement with red lead in the 10A jack and black into COM jack. When I read the directions with more daylight and no beer, the red lead goes into VΩmA and black goes to COM.

With the correct setup , the batter reads in excess of 14 volts with the car running. So now question becomes is it normal to drain in a weeks time?


Lesson learned. First time use of multi-meter should be in plenty of light and no "fluids".

Thanks
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Old 11-12-2017, 12:53 PM   #5
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Do you have a 6 disc changer in it?
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Old 11-12-2017, 01:32 PM   #6
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Do you have a 6 disc changer in it?
Yes, I do have the stock 6 disc player. Is that a potential battery drain issue?
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Old 11-13-2017, 10:24 PM   #7
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Thanks for the suggestion IMP. Turns out, I had the leads plugged into the wrong holes on the multi-meter. I had it set up for DC Current Measurement with red lead in the 10A jack and black into COM jack. When I read the directions with more daylight and no beer, the red lead goes into VΩmA and black goes to COM.

With the correct setup , the batter reads in excess of 14 volts with the car running. So now question becomes is it normal to drain in a weeks time?


Lesson learned. First time use of multi-meter should be in plenty of light and no "fluids".

Thanks
Absolutely not. However, it sounds as though you are using an analog meter instead of digital. The cause of draining the battery almost surely is not drawing 10 amps, so the ammeter 10 amp. scale could be used to determine how much current is being drawn, then, remove likely fuses one at a time to locate WTH is drawing the current. IF you do this do it THIS WAY. Disconnect the battery + cable, and connect it back to the post using a length of wire, jumper cable would work, as it has big clamps. THEN connect your ammeter +10A lead to the battery + and the COMMON lead to the battery cable + terminal in such a way that you can remove the jumper clamp, leaving the meter in the circuit.


Reason for doing this that way is there are high-current draws for very short time when reconnecting a battery cable, due to big capacitors in power supplies for air bags, for example. You want those babies charged up already when you get the meter connected. The jumper cable ensures that. Doubtful the parasitic drain is more than 10 amps, if it were, the battery would go down overnight. Please ask if you do not understand what I'm suggesting in any way. Good luck. imp
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Old 11-14-2017, 09:06 PM   #8
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Yes, the 6 disc changer is a known problem that will drain your battery..if you turn the car off, you might be able to hear the cd changer shuffling the cd's in there. Also, if you have the shaker system, the amps can kill the battery. To avoid that, turn the radio off before turning off the ignition. There are plenty of instances if you just google it.
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Old 11-18-2017, 03:23 PM   #9
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Thanks ucinn, after you asked the question, I googled and learned this is a known issue. So I will be sure to turn it off and empty the CDs.

IMP, thank you too for the troubleshooting tips. I appreciate it.
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