battery dies everytime

[SSS281]

everytime i leave my battery connected and let the car sit, by about 2-3 days later it will be dead. the car used to sit 6-7months at a time w/o starting and then fire up right away. so i figured the old motocraft battery finally had enough and i got a optima red top. same problem! i dont know how this wouldve started, the only thing ive changed about the car is actually removed the entire stereo system. there's nothing in the car that i can think of that would drain it.

any ideas? does a stereo need to actually be there to complete the circuit?

 

[four six]

Same crap happening to me lately. A few people told me that its because something drawing from the battery(Amp, radar, etc) IDK Is it real cold where your at?

 

[DTNODYA]

Something is definitely draining it. Mine has been doing that crap for like 2 years now ... Until I installed a switch (so I can cut it off when sitting for like a week), now it's never dead.

 

[four six]

Something is definitely draining it. Mine has been doing that crap for like 2 years now ... Until I installed a switch (so I can cut it off when sitting for like a week), now it's never dead.

Hows that work? Is it just a battery quick disconnect? Where did you get it? Thanks

 

[DTNODYA]

I got the switch from boaters world when I went to pick up some 303 Aerospace Protectant one time. It's basically just a switch that I connected my ground terminal wires from the car to one side and attached the other side to where it was originally grounded. So basically when you flip the switch, it breaks the ground connection thereby disconnecting the battery. The only thing that I haven't figured out yet is how to make it where I don't have to re-set my radio settings every time. It's worth it though (to me) for my battery not to be dying every 3-4 days!

Here's a picture:



And the other day, I got bored so I did one for my truck too. It's cooler than the one on my Mustang because after you turn the knob to the "off" position, you can pull the knob out (hella good anti-theft device) ... A pic of it:



I'll give you more specifics if you decide to try it. Not very difficult ... and a good time to upgrade those factory crap battery terminal connectors.

 

[the98stang]

maybe the altenator isnt working?

 

[COramprat]

Could be a weak alternator. Take it to Auto Zone or someplace and have them test it.

 

[four six]

Well MY alternator, starter, and battery are brand new. My battery was dead yesterday when I was leaving for work @ 3:30am . I had the battery replaced so IDK it should be ok now

 

[urban96]

make sure your not getting any draws when the car is off. you can test this with a multimeter. i was having problems like this b4 and it turned out it was something to do with the rear defroster. its a summer only car so i just pulled the fuse for it and problems are gone.

 

[SSS281]

how can you test what is drawing from it? it is real cold here now however it has been doing this since summer. its getting to be a pain because the computer resets every time correct? is that not bad for the car to have to re-learn every few days? i cant imagine it be normal to have to disconnect each time u stop even if it just sits for a few days. like i said this thing used to sit for good amount of time without problems, the only thing ive changed is removed the radio, that wouldnt casue this would it?

 

[SaleenGT2001]

mine is the same way

 

[03ghoststang]

how can you test what is drawing from it? it is real cold here now however it has been doing this since summer. its getting to be a pain because the computer resets every time correct? is that not bad for the car to have to re-learn every few days? i cant imagine it be normal to have to disconnect each time u stop even if it just sits for a few days. like i said this thing used to sit for good amount of time without problems, the only thing ive changed is removed the radio, that wouldnt casue this would it?

to do an amp draw you take your multi meter and put a aligator on one of teh leads and place it on the negative battery terminal and the other diretcly on the negative battery post. But before all this loosen up the terminal and attach the leads so after you can slip it out of the post all while maintaining the cicuit closed

 

[urban96]

how can you test what is drawing from it? it is real cold here now however it has been doing this since summer. its getting to be a pain because the computer resets every time correct? is that not bad for the car to have to re-learn every few days? i cant imagine it be normal to have to disconnect each time u stop even if it just sits for a few days. like i said this thing used to sit for good amount of time without problems, the only thing ive changed is removed the radio, that wouldnt casue this would it?

to do an amp draw you take your multi meter and put a aligator on one of teh leads and place it on the negative battery terminal and the other diretcly on the negative battery post. But before all this loosen up the terminal and attach the leads so after you can slip it out of the post all while maintaining the cicuit closed

thats the method i was thinking of. i guess you could sorta also use the same method on each circut in the fuse box under the hood to see what one is drawing power.

mine was kinda a dead giveaway because the little defroster LED stayed lit

 

[Pennywise2]

I bet you that you have a bad alternator.
Have your alternator and charging system tested for sure.
Your battery shouldn't be dead after 2- 3 days from your car sitting.
Their is something wrong obviously.Alternators really aren't
that expensive to replace anyway if that is the case.

 

[Turbo92PGT]

Mine does it too. Newer battery, new alternator. I'm gonna charge it and try the amp draw test. stupid thing.

 

[newstangman]

Try this and let us know what you find:

http://www.wikihow.com/Find-a-Parasitic-Battery-Drain

 

[urban96]

Try this and let us know what you find:

http://www.wikihow.com/Find-a-Parasitic-Battery-Drain

good link!

 

[03ghoststang]

thats the method i was thinking of. i guess you could sorta also use the same method on each circut in the fuse box under the hood to see what one is drawing power.

mine was kinda a dead giveaway because the little defroster LED stayed lit

well the way i do it is start pulling fuses and placing them back until i see the volt meter read zero then that is the circuit drawing the current

 

[1low03gt]

Usually the altenator is the cause,or a bad ground,or even the the battery teminals if they aren't cleaned properly for a proper connection.
Like others have stated,get the altenator tested,if good,start checking your ground straps for rust,or undercoating that could be making a bad connection,and check the battery terminals for bad corrosion between the positive,negative cables and terminals this too makes for bad connection.
Hope you find find your charging issue! Good luck!

 

[1wildGT]

make sure your not getting any draws when the car is off. you can test this with a multimeter. i was having problems like this b4 and it turned out it was something to do with the rear defroster. its a summer only car so i just pulled the fuse for it and problems are gone.

I had the same problem when my 2002 GT was brand new. The rear window defroster circuit was faulty, the button would glow when everything else was off and battery would die in about 2 days. Dealer never could narrow it down, so I just pulled the under hood fuse for the rear defroster circuit. Weird stuff.