help. battery always goes dead

[pamike]

been having this problem for a while now and i'm really getting tired of this. theirs some details of my problem here
http://www.ultimatesubaru.org/forum/sho ... p?t=117124 (http://www.ultimatesubaru.org/forum/showthread.php?t=117124)
anyway, i noticed a very faint humm when listening around the top of the motor and i found if i unplug the iac valve, it stops. and if i plug it back in it humms again. while doing this the battery volts goes from 12v down to 11.95v and back up when i unplug it again. so it seems to me that somthing is on that shouldn't be. now my question is should i have any power to the iac valve connector with the key off? i'm getting 11.5 volts at the connector on the left and middle wires when looking at the connector. after messing with it for about a half hour i checked the volts at the iac connector and got barely nothing. then after turning the key on and back off i got 11.5 again at the connector.
so is this normal for this to have power for a while after the car is turned off?

[Yokosilver]

That sounds like a capacitor discharging, the way the voltage drops after a while of testing with the key off. You could always test your iac to see if it works.

http://www.2carpros.com/articles/how-a- ... alve-works (http://www.2carpros.com/articles/how-a-idle-air-control-valve-works)

In case you weren't sure how to test it.

[pamike]

thats what it sounds like. but i dont believe it's the iac. i just need to know if voltage to the iac connector with the key off is normal. also i just took the car for a run. when i got back i cycled the key on and off to try to get the car to make that noise again and it wouldn't do it. very little power at the connector. i think it was .057v.

EDIT- i just tried turning it on and off and starting it and i couldn't get power to the connector with key off. i have a good feeling this is the problem because the battery doesn't always drain. it once sat for a month and still started fine. so what can cause this? somthing ignition switch related?

[Yokosilver]

I'm not sure. Unfortunatly I don't know a lot about car electrical systems. I'd hate to say take it to a stealership and have them do an electrical test, but it might come down to that. Maybe you know someone who can look at it for you.

[Wiscon_Mark]

First thing's first:

Go to autozone or advance auto or whatever auto place you have close by.

Get your alternator & battery tested. Most places do it for free.

[96LegacyWagon]

mind you i'm a car n00b here, but the first things i would check in this case would be your relays, switches and fuses related to the circuits in which you are having the problem(s).

[pamike]

i am 100% sure the battery and alt are not the problem


mind you i'm a car n00b here, but the first things i would check in this case would be your relays, switches and fuses related to the circuits in which you are having the problem(s).

this is a great idea. it could be somthing as easy as a relay sticking. i just need some wiring diagrams to figure this out.

[pamike]

i started pulling fuses in the under hood box. when i pulled this green 30 amp one the power at the iac went away so i'm assuming this is the circuit i want. here is a pic of it

http://i295.photobucket.com/albums/mm132/pamike/other/SANY0310.jpg

in the center of the pic it's the big green fuse. there are 2 of them. one on the right is the one i'm talking about. the fuse box cover has it listed as 30a SBF NO 2. my haynes manual shows this going through a relay labeled main relay to the center wire of the iac connector. so where is this main relay located?
and it looks as if the relay is powered by the ecu (mpfi control unit in the haynes manual) so it would almost have to be a bad sticking relay or somthing is wrong with the ecu and its powering the relay when it shouldn't be. so i think i really need to find this relay.