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Discussion Starter #1
I have to start my car every 3-4 days or the battery will be dead.So I'm assuming I have a phantom drain on my battery is there any that are common,and how exactley do I check for the drain?
 

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To check for a draw you can disconnect the negative battery lead & put a test light between the lead & the Battery. See how bright it glows. You can start disconecting things one at a time by unplugging or pulling fuses until you find it. I've heard of pwr mirrors causing problems & a bad alternator can cause a draw. You may want to have your battery load tested, it could be weak (no capacity).
 

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If you have an underhood light make sure it isn't staying on. The glovebox also has a small light in there that may be staying on. Another common problem is the vanity mirrors with the lights. Sometimes they don't like to go off when you shut the little mirror cover.
 

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Discussion Starter #4
Well I have no power accesories in my car and I don't have lighted visors.No hood light and I even took out the bulb out of my interior light so that wouldn't be a drain at the track.I jumped it this morning and got it started it ran for about 7 minutes and then I had to go to work.Came home and it's so dead that the fuel pump won't even prime.The battery isn't even a year old and the alternator and battery cables are less than 3 months old.
 

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What I did when i had my phantom drain was borrow a DC ampmeter. I unhooked the battey and touched one probe to the batt terminal and the other to the cable. The draw with the car of should be less than 1 amp normally. Start pulling fuses and checking the draw. If there is something drawing more than 1 amp, you can isolate it.

My problem ended up being the hood light staying on
 

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Is your ingnition switch timed right? If you have to twist really hard on the key to get a crank it's not. Some idiot did this on my car before I got it. It took a while to figure it out. When the switch would lock and let the key out it was on accessory in the column switch causing a constant drain.

Vernon
 

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Do you clean your battery? Take a digital voltage meter and touch it to two spots on the top of the bat on the plastic there's a good chance you will see voltage. If you do that's a parasitic draw that is draining your battery (not necessarily your problem). To clean your bat mix some baking soda with water and brush it or pour it on the bat it will fizz that's it neutralizing the acid residue then just wipe all the liquid off and rinse it with clean water. DO NOT! get any in the vents or it will kill your battery. Its a good idea to do this once and a while your battery will last longer. Hope this helps.

Regards, John
 

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Have had the same problem. Checked everything as mentioned above, it turned out to be my alternator. I even had that checked out.
 

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i just started having this problem and i dont even drive the car.
but im thinking car alarm.
last time it was my heater motor it would drain the battery as i drove, i thought it was draining as it sat.
defiantly use a amp meter ill be doing that this weekend.
 

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do you have big stereo equipment? i had a relay turn on deal for 2 amps and the voltometer said no problem but then i twisted the 2 amp remote turnon wires together threw out the relay and its fine, i originally had them relayed because i thought it was a lot of watts to turn on but its been great since, dont take your car to best buy even if its free, they like to splice your amp into your fuel pump hot wire...damn bastardz...took me 2 hours of undoing their damage all in the name of being cheap thinking i got a good deal
 

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4play and Mustang5L5 are right... the only good way to test is to pull the battery cable, put a test light inbetween the cable and the batt and if it is glowing, you've got a problem. The next thing is to start pulling fuses and eliminating circuits that could have a short or bad piece of equipment. If you DO end up pulling all of your fuses out and you still have a draw, it's more than likely your alt and it wouldn't supprise me one bit (with a draw that strong, I have a feeling that is what it is).

BTW, that year old battery is shot now... you can only cycle a car battery a few times before it starts loosing it's grunt. I would eliminate the problem and then replace the battery once it's all fixed.
 

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Yeah autozone checks your alternator, they say its good, there aint nuthin wrong, but they cant do a diode check i think thats it? so if the diodes are bad or something itll cause that drain problem. i remember that because they cant check something on alternators and i went round and round with them guys.
 

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well it's funny that i have had the same problem for the last 6 months, and doing everything on this board for suggestions hasn't worked. the test light shows nothing, alternator is brand new, brand new optima red top.. what i have been told now is to check all grounds, not just motor grounds, but all grounds to aftermarket guages and the like... so the hunt is still on for me
 

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The most common problem is the voltage regulator, whether it's external or internal. Try unplugging it and see if the problem goes away.

HiTech
 

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had the same problem, do check the voltage regulastor, the little black thing on the back of the alternator, replace it if it is bad and not the whols alt. a 130amp alt. is expensive. believe it or not try your starter motor, even if it sounds fine when you start the car it could be going that was my problem
 

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I too had a mysterious drain, for the longest time I couldn't find it. Ended up buying a DC clamp meter from lowes for like $40. This way you don't have to break the circuit to measure current flow.

My problem ended up being the key on circuit that cuts the voltage regulator on. It was exciting the voltage regulator all the time instead of just when the key was on. This produced a steady 4 amp draw.

btw, those roll around testers that parts stores use to test alternators and batterys will test for bad diodes.
 

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How old is the battery? If the battery is more than 1 or 2 yrs old or even brand new the battery could be bad. I worked at Kragen Auto parts for 10 years, usally the battery is bad. Batteries do not last in Fords.
 

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Greg Lawrence said:
Yeah autozone checks your alternator, they say its good, there aint nuthin wrong, but they cant do a diode check i think thats it? so if the diodes are bad or something itll cause that drain problem. i remember that because they cant check something on alternators and i went round and round with them guys.
AutoZone can check the diodes. You have to take the alternator off of the car and take it in to the store. They have a test bench that will do a better job of checking the alternator than the one they use while the alt is still in the car. I used to work at AutoZone, 5 years ago. They still have the same test bench.
 
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