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Try disconnecting the battery next time you let it sit for several days. Reconnect it and if it starts up fine, then you know for sure there is a current draw on the system. Most likely the dome light circuit, since the radio only comes on with the ignition key on. Check the charge before you start it and after running for a while, too. That will tell you if the alternator is charging, or you can unhook the positive cable while running (on non-computer motors ONLY). If the motor dies, the alt is bad.
Remove the bulb from the dome light, or install a cutoff switch, because that's more than enough to drain (and eventually render useless) the battery. I had a similar thing when once I left the glovebox opened (had a light in) and not only the battery was completely dead after 2 months, but it wouldn't take charge very well any more.
Do you have an aftermarket radio in it? Sometimes people miswire them, allowing the display to stay on when the key is not in the ignition.....if so, that would definately drain your battery.
The other suggestions are good starters as well, check the easy things first ( glove box light, dome light, underhood light ) and simply yank the bulbs out of them, let is sit for a week or so and see if it helps.
The tried and true way is to put an amp meter in series with the battery and see if there is ANY current draw then start pulling fuses one at a time until you see the amount of draw change. At that point, you've isolated the circuit. How old is the battery?
the battery is only like 3 months old, and it is definately not the alternater
the dome light is unscrewed enough to where it doesnt light up and the face plate to the radio is off of it but i was wondering if even then it could still draw it down or something associated with them that is not visable
sorry but i will be outa touch for a few days, i'll see what i can find though
see if there is ANY current draw then start pulling fuses one at a time until you see the amount of draw change. At that point, you've isolated the circuit. T
This is correct on older vehicles, but newer vehicles will draw some current (I measured, I believe 10 mA or so on my '95 Bronco) . Pulling fuses is somewhat pointless if the current draw is under some limit -- like 10 - 20 mA since it will reset the clock and the computer, and at the end one will conclude that the clock and the computer are drawing some current....
You are correct, I forgot to mention that. But he will be able to isolate the draw on his system, because it will greatly exceed 10ma if it is killing the battery every week.
[QUOTE=Beastybroncothe2nd]i have a new battery that dies when i leave the truck sittin for a couple weeks or so
QUOTE]
Sorta depends on how long the "or so" period is: if it turns out the battery is getting low after 4 - 6 weeks, well that's pretty normal and could easily be caused by no more drain than a clock or an onboard computer.
I've got an old pickup I only drive once every month or so, and to stop its battery from going dead I finally installed a battery cutoff switch for around $20. Of course you have to reset your radio every time you start up, but at least you start up!
Sorta depends on how long the "or so" period is: if it turns out the battery is getting low after 4 - 6 weeks, well that's pretty normal and could easily be caused by no more drain than a clock or an onboard computer.
it has been between 2 and 3 weeks
im pretty sure the alternater is the ok because after i do get it running it charges up fine and will crank up for a couple of weeks but if i dont run it again it looses the power
oh, and redbob thats a good idea but if i cant figure out whats drawing power i will prolly just pull off my battery cable when i will be leaving it sittin
The voltage reg. could be bad and causes the battery to die when sitting, sometimes overnight. The regulator is in the alternator so it requires replacement. Pulling a battery cable while the engine is running will cause the engine to die and does not indicate a bad alternator. The reason is, alternators have no iron core in their field windings to hold residual magnetism and rely on current flow from the battery to the field windings produce current. When you disconnect the battery, current flow thru the field windings stops and current production stops, resulting in the engine stopping.
I was working on my girlfriend's Toyota today (battery dies after several days) and I measured 200 - 250 mA current draw on the battery when everything was OFF. You should measure the current draw, or ask someone to do it for you.