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Battery DEAD after sitting......

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Old 10-25-2006, 08:03 AM
  #1  
Katmandu
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Default Battery DEAD after sitting......

....for a day or two.

I recently bought a 91 GT Vert. It has a problem with the battery going dead after sitting for short periods (day or two).

I had the alternator and battery both check out and both were deemed OK.

What's the Troubleshooting process from here ??
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Old 10-25-2006, 10:20 AM
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4fit?
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Default RE: Battery DEAD after sitting......

Start checking grounds. You have a draw somewhere.
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Old 10-25-2006, 10:28 AM
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aode08
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Default RE: Battery DEAD after sitting......

your sunvisor or trunk light may be staying on(common)


on sevearal 5.0's the negative battery cable was at fault.
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Old 10-25-2006, 10:30 AM
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4fit?
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Default RE: Battery DEAD after sitting......

ORIGINAL: aode06
on sevearal 5.0's the negative battery cable was at fault.
+1
Mine was the smaller gauge ecu ground coming off the battery. That summabitch would actually smoke when I cranked he car.
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Old 10-25-2006, 04:26 PM
  #5  
fourfivefour
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Default RE: Battery DEAD after sitting......


ORIGINAL: Katmandu

....for a day or two.

I recently bought a 91 GT Vert. It has a problem with the battery going dead after sitting for short periods (day or two).

I had the alternator and battery both check out and both were deemed OK.

What's the Troubleshooting process from here ??
After checking the obvious things that can stay on when the car is turned off and you dont find any thing then check for a draw. Confirm everything is turned off. Disconnect the negative battery cable. Connect a test light between the negative cable end and the negative battery post. If you have a draw the test light will light. A dimly light test light is ok it is powering the clock and computer. But if it is on bright start disconnecting added accessories one at time or pulling fuses one at time and close doors and unplug hood light. When you find the circuit that is drawing the test light will go out. Also check your cig lighter a coin in there or a bad lighter element can cause a draw too.
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Old 10-25-2006, 04:51 PM
  #6  
Hung Like a Stang
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Default RE: Battery DEAD after sitting......


ORIGINAL: fourfivefour


ORIGINAL: Katmandu

....for a day or two.

I recently bought a 91 GT Vert. It has a problem with the battery going dead after sitting for short periods (day or two).

I had the alternator and battery both check out and both were deemed OK.

What's the Troubleshooting process from here ??
After checking the obvious things that can stay on when the car is turned off and you dont find any thing then check for a draw. Confirm everything is turned off. Disconnect the negative battery cable. Connect a test light between the negative cable end and the negative battery post. If you have a draw the test light will light. A dimly light test light is ok it is powering the clock and computer. But if it is on bright start disconnecting added accessories one at time or pulling fuses one at time and close doors and unplug hood light. When you find the circuit that is drawing the test light will go out. Also check your cig lighter a coin in there or a bad lighter element can cause a draw too.
its better to use an ammeter. If you're drawing more than 30ma, then you have an excessive draw. However, your battery could just be sulfated, have someone to a load test and a 3 minute charge test on it, always start at the power source.
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Old 10-25-2006, 05:41 PM
  #7  
OnyxCobra
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Default RE: Battery DEAD after sitting......

ORIGINAL: Katmandu

....for a day or two.

I recently bought a 91 GT Vert. It has a problem with the battery going dead after sitting for short periods (day or two).

I had the alternator and battery both check out and both were deemed OK.

What's the Troubleshooting process from here ??
I had autozone check my battery b/c i was having a similar problem. They told me twice my battery was okay, but i bought a new battery anyway and have had zero problems since.
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