Battery goes dead in 5 days! Any ideas???

The one month old battery in my 2000 GT is going dead after the car sits for 5 days or more. I replaced the battery at Thanksgiving as I first thought after 5 years it lived its life. The new one has 12.5 volts when the car is off and 14.6 volts with the car running, so I know the alternator is generating. When disconnected from the car the battery does not leak down. The car is bone stock, with the exception of a cold air intake. Nothing is plugged into any power outlet. Nothing has been "left on".

Has anyone had this problem? Short of pulling fuses and trying to replicate the problem for each circuit, any ideas on how to chase this down?
 
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The easiest way is to remove the positive terminal,put a test light between the terminal of the battery and the cable. If it lights up,even slightly then you know there is draw form the car. Start pulling fuses until the light goes out,then you've found the circuit.
 
Cars will drain batteries if they sit for a week or more. It's due to all the electronics on board. And if you have an alarm, it will draw even more. My car did the same thing.

Best thing to do is unhook the negative terminal altogether before you leave the car to sit. OR, if your car sits outside, buy a solar panel/charger and sit it on the dash, that should keep a trickle charge going to the car.
 
Spreadman said:
Cars will drain batteries if they sit for a week or more. It's due to all the electronics on board. And if you have an alarm, it will draw even more. My car did the same thing.

Best thing to do is unhook the negative terminal altogether before you leave the car to sit. OR, if your car sits outside, buy a solar panel/charger and sit it on the dash, that should keep a trickle charge going to the car.
Yeah, but even still. Dead after sitting only 5-days is excessive. I would pull it from the car and put in on a trickle charge (2-4 amps) for approx 12-16 hours, then pull the caps off of the top of the battery and check the electrolyte levels with a hydrometer, then check it again in another couple of days to see if it's dropped. You'll know for sure then if it's a battery problem or not.

This is a hydrometer, in case you aren't sure and they're all of about $10-20 to buy.

battery_hydrometer_md.jpg
 
My thoughts exactly, Gearbanger. The car is bone stock, as far as the electrics go and only has 64K miles on it. I can't imagine a dealer having to charge all of their cars' batteries every 5 days. It sat at an airport parking lot for two weeks last summer with no problems. It has drained down 3 separate batteries. I know the one battery is good as it is out of my street rod. I checked the electolytes before putting it down for the winter.

Anyway, I just put my voltmeter between the positive terminal and the disconnected positive wire. I got a reading of 0.02V, which could be the factory radio and clock memory, as well as the factory theft system. Time to start pulling fuses.

Hey, I'm not asking anyone out there to go pull your battery termials off, but just in case, does anyone know if 0.02V is an acceptable draw?

One other question.... How about the voltage regulator? If defective will it allow power to draw back?
 
what type of battery did you put in? some of the newer batteries are sealed or maintianence free. i know where i work, our batteries come with the covers, but they dont get taken off, we dont use water in ours, its a diff fluid.
 
Red2000GT said:
The easiest way is to remove the positive terminal,put a test light between the terminal of the battery and the cable. If it lights up,even slightly then you know there is draw form the car. Start pulling fuses until the light goes out,then you've found the circuit.


make sure you run a jumper wire to keep the battery conected so when you remove it the jumpers are connected.. then put one lead from your multimeter or drop light on the positive terminal and the other on the pos battery cable.. then unplug your jumper wire..

this is IMPORTANT do not skip.. in all modern fords if you disconnect the pos terminal and leave it unconnected from the battery, once you make a connection too the battery again.. all modules are now in awake mode.. this will give you a false draw...

so this is what you want too do..

1. connect a jumper wire one end too the terinal and the other contacting the battery post..

2. disconnect the battery cable.. make sure too keep the jumper wire in contact with both the terminal of the battery and the cable at all times..

3. connect your test tool of choice..

4. remove jumperwire...

durring all these steps the battery has always had somthing touching the pos terminal and the pos cable at all times..
 
i have the same problem but found that if you turn the radio off before the key goes off it doesnt drain 06 gt not even two months old grrrrrrr taking it back to ford hope this helps
 
That sounds like a bizarre test sequence, but hey, glad you can help. That's why I asked.

I already have the leads off the battery as I am tracking how many volts the battery leaks down when not hooked up (it dropped 0.05 volts since Saturday at 8AM WITHOUT having anything attached to it). I will reattach it, run the car, then go through the test as you suggest. I did not have the jumper wire on it previously.

BTW, it is a Bosch battery and yes, the caps are removable and the electrolytes are satisfactory.

If I had this happeniing to an '06, I'd be saying more than "grrrrrr".
 
Your new battery is defective, take it back where you bought it and get another. If the car wasnt running down the old battery then the car isnt the problem....obviously.

Dont over think it. Its the battery.
 
The easiest way is to remove the positive terminal,put a test light between the terminal of the battery and the cable. If it lights up,even slightly then you know there is draw form the car. Start pulling fuses until the light goes out,then you've found the circuit.

If that (the fuse test light thing) does not work check out your alternator. A diode(s) may be going bad or already be bad go allowing backward electron flow. The alternator will or can still charge enough to keep the battery topped off most of the time. But I will test only marginal. And another thing that will drive you crazy is it may not discharge the battery every time! A rebuild found my problem so I do not know how to diagnose it at home. Good luck.