Dementia

Cliff notes- Does anyone know what the amp draw should be with the car shut off? Mine is currently as .10 amps.

I'm having electrical issues. About a week ago my battery was dead. I thought nothing of it, maybe a door got left open. I discovered shortly after that the gear strip in the antenna had snapped. I thought the motor probably ran all night and killed the battery, since the same thing happened a few years back in my altima. Yesterday the battery was dead again. I started with my stereo system, but it wasn't drawing any power. Then fuses were pulled one by one to watch for a drop in amp draw. The amps finally dropped when the "BCM" fuse was pulled (in the fuse block under the hood). BCM stands for Body Control Module. It controls all the little crap in the car... lights, switchs and such. When this fuse was pulled, them amp draw dropped from .10/.11 to about .02.

There is also the question of whether my battery is toast. It is a less than 1 y/o Optima. It was charged and was about 12.5v when it was done. The battery was disconnected and left over night to see if it would lose voltage on its own, but it did not. So the battery seems ok.

Any thoughts would be appreciated.

theblackmax455

iTrader: (3)

Im gonna post a really stupid question here, but should there be any amp draw w/ the car off? I can't see why, but if so I'm always up for learning something new.

Dementia

Memory for your stereo, sensors for alarms. Things like that. I talked to numerous dealerships today trying to find out what the amp draw should be. Only one guy thought that .10 amps was to high. Everyone else told me that it was in the normal range, that it should not be killing my battery and that the BCM will draw the most power when the car is off.

I think I'm just going to exchange my battery even though it doesn't seem to be the problem, and then just go from there.

vortechpower

iTrader: (1)

Optimas should last along time. The benifit of them is that you can run the dead and charge m up again like new.. An amp shouldnt draw any power when the car is turned off. ??

z32drifter

lets see.... I am on my 3rd Optima battery ........ red tops... 1 I got less than a yr out of.... 1 just under 2yrs and the other 1 is going on 3yrs.... if I rember correctly my car had a similar draw.... same condition pull the BCM fuse... no draw.... the level of draw is diff from car to car.... I work on Audi/VW and the normal draw is around 15mA .. but those cars start with a draw around .20A then as the modules shut down "go to sleep" the draw drops..... I don't think the Nissan modules in our cars ever go to sleep.... and since they stay active ... they draw more current... when I tested my Max.... I was worried about the draw, until I tested my 94 Z .... It had a .25A draw.... and sits in the garage for weeks at times.... never had a problem starting it.... take your battery and have it tested.... I bet you will find it is the problem

Hrap

'98 GXE with stock setup has no-load battery drain (measured) of 8 ma. That's 0.008 amps. If you are seeing 100ma drain it's probably sufficient to drain the battery over a period of non-use.

Dementia

We replaced the battery... it had a bad cell. The new optima we got had a low charge off the shelf... but did start the car. It however does the same thing, after 5-7 days of not being started it almost doesn't have enough of a charge to start the car.

and I mis-typed before... my car pulls .010-.011 from the BCM... so about 10mA.

Maybe another crappy battery

nstjohn

I have a similar problem but my drain is about 200mA. According to Haynes the draw should be about 20mA. Also see this link:

http://groups.msn.com/AllAutomotiveQ...02336190472623

Also note the hood switch could cause some current drain if you are testing with the hood open.


-Noel

nstjohn

I found my problem. Please see here for the explaination:

http://forums.maxima.org/showthread.php?t=374127


-Noel