Mystery current draw from Battery

[anchovies]

I've tested the draw by putting a voltmeter in series with the battery neg cable and post. It draws 12v. Took out alternator cable. It still draws 12v. Took out every fuse, still draws current.

Am I doing it wrong? Or is there something drawing the current.

Thanks

[88LXi/87CRXSi]

Seems u may just be measuring voltage. to measures current draw, your meter would have to have a d.c. amperage (current) function. You would hook ur meter up also in series, probably have a different hole for 1 of the meter probes and put the meter in the D.C.A. range. (Don't start ur car!!:eek: ) then u can see what the amp. draw is. I'm guessing it would be real small, like .005 amps. If I'm off, I'm sure someone with more smarts will give you a correct or less confusing explanation.

-Steve

[Dutchboy]

or use a test light...

unhook the negative cable and see if the light lights up.....if it does do what you were doing....take out the fuses one by one until it goes out..
remember theres fuses under the hood and the dash.

Ben

[cruznz]

yeh...u need to use your meter on amps dc......in series

[anchovies]

ohhh amps :D
thanks guys..let me try that
now need to borrow that stupid meter again

[AccordEpicenter]

Use the meter in series with the car to measure current (undo neg battery cable, connect meter between neg battery cable and neg battery post) and with everything off or closed with the key out of the ignition (all doors closed, no lights on) the car should read at or near 10mA worth of current draw. If its much higher than that (say 100mA or so) then start pulling fuses until the draw drops to around 10mA, youve found the problem circuit. If you do have a problem with current draw its prolly the circuit with the horn/interior lights/seatbelts (should be like a 10amp fuse) and that is usually caused by the seatbelts (somthing stays on or somthing, not sure why, and only in the coupe) any qs?

[anchovies]

yeah..
what's the square root of 65536? :D

thanks guys..i need to test it again..
maybe this can go into FAQ for electric bums like me

[anchovies]

okie...i got 0 amps. I've even tried with the micro amp, still nothing. You guys got some reading. Should I be worried about this? Or am I doing it wrong. I did exactly you guys said.

[88LXi/87CRXSi]

Out of curiosity, I went out and hooked up my meter. On the 0-10 amp range I got nothing, on 0-200 milliamps range I read 24 ma, clock, ecu & stereo mem. Hope thats not too high! :crying: About yours not showing any draw, it's possible that the meter has fuse protection thats open. You could try, say, for instance, openning a door. If the light doesn't come on, u don't have a complete circuit thru your meter. Also, on my meter, I have to plug one probe in the common hole, and one in the 0-200ma hole on the front of the meter, or no reading. Micro-amps, I don't have, probably would be overranging if it did. Other than that, maybe ur electrical system is just ultra-super-effecient! :huh: Are you draining the battery overnight or anything to lead you suspect problems?

-Steve

[cruznz]

well if you checked voltage with meter on Adc,you may have blown the internal fuse....with the meter on ohms,ues positive probe to check,just probe the Amp inputs ....on the mA input you should get a reading of about 4-8 ohms....on the 10amp you should get a reading of about 0.3 ohms....no reading on either means blown internal fuse...........these readings are for my fluke meter.....and the fuses for these a exspensive....a trick is to put an inline 8amp fuse on the positive probe to protect the internal 1

[anchovies]

No, my system is not ultra efficient. I'm ultra boink on the head. So I plug to a common hole (wth is a common hole? :D) and another on one ma hole (sorry I don't have that meter with me right now). But the holes are named right?

So how do I easily check if I have blown the internal fuse on the meter? Say check with an AA battery or something at home. This meter is my friend's and he'll kill me. :(

Thanks for the help guys. I'm just checking my system for draw because my old battery went dead after a week of not starting the car and now I've a new battery.

[cruznz]

leave meter connected for checking volts,("common" is the negative probe),...switch meter to Ohms.......using the positive probe...(there are 2 inputs for amps?.....10amp...possibly....and another at about 300Ma)....probe these inputs....blown fuse will give an open circuit reading

[BoredRec]

Why are you doing a current draw test? You go out to your car each morning and the battery is dead?

[anchovies]

Yeap...the fuse is blown :( I've to get a new fuse. For those who know, what else to check to make sure I didn't fucked up this multimeter?

And BoredRec, just trying to find out if the car is drawing too much current. My previous battery when dead after a few days of not starting (might be old - original Honda battery!!!) and now I have a new battery, but I drive the car everyday and cold weather doesn't help with cold starts either. I just want to make sure the system is not drawing current and kill my new battery.

[pimp86LX]

hmm that brings up a good concern, i'm worried about current draw with my cdplayer, clock, and etc etc.

question: What would be a good idea of how much mA or A a cd-memory would draw?

[cruznz]

just get another fuse for it ....its not an ordinary 1 either........if you want to avoid blowing the fuse all the time just put an inline fuse on the positive lead with a 8amp fuse as i think the internal fuse is about 10amps