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09-16-2010, 05:41 PM
#2
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Location: Hudson Valley, NY
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I would put 12v tail light in line to see which circuit is drawing the most juice. Put bewtwwen the neg terminal and the neg cable so that it is in the circuit. Pull all od the fuses and insert each one, one at a time. When you see the bulb light up you will know which circuit is drawing some juice. The "brightest" circuit will be the biggest draw. Track it down from there.
Yes, you can just pull the alternator wiring to drop if from the system to see if it is also drawing.
Yes, you can just pull the alternator wiring to drop if from the system to see if it is also drawing.
09-17-2010, 01:35 AM
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Couldn't find a tail lamp with a socket that I could wire up easily.
So I tried the multimeter. I've read voltages before a lot with it, have never used it to read mA. So I followed a post I found. Black to COM on meter, Red to 10ADC.
Put it in-line from Neg cable to Neg batt post. Reads 14.9 - 15.1 on the 200m DCA setting. Am I reading that correctly, just 15mA?
So I tried the multimeter. I've read voltages before a lot with it, have never used it to read mA. So I followed a post I found. Black to COM on meter, Red to 10ADC.
Put it in-line from Neg cable to Neg batt post. Reads 14.9 - 15.1 on the 200m DCA setting. Am I reading that correctly, just 15mA?
So disconnecting your positive post off of the battery, one probe (red) would go onto the battery post while the other (black) would go onto the positive battery cable.
You'd then set the meter to the closest it can come to giving your the reading or set it for 'auto' mode if it's a digital.
If it's analog then set it to the closest display on the face of the meter to mach what input you're using to get your reading.
And yes, that would read 15ma on that scale you used.
I think you got it right.
Try also using a smaller setting instead of your 10 amp scale for your amp readings unless you're worried about blowing the fuse on your lower current scale.
So set it up the way you had with all the fuses out and you should get little to no reading on the scale. Start installing fuses until you see a jump. Go from there.
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09-26-2010, 08:44 PM
#9
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10mA is such a small draw that it won't drain the battery for weeks.
That's .0105 amps and considering that there's approximately 600 cranking amps in the system of the battery, it's not worth mentioning.
Alternator diode will have some kind of leak down but it will be a minimal amount that should not hurt or draw that much to make a difference in the batteries loss.
All diodes do this and can't present a perfect blockage of voltage through it's junction. It's not possible.
Try removing all the relays if necessary and take another reading.
So you're still having issues with the battery dying in a short period of time?
I'll tell you that in 2-3 weeks, my battery in the Porsche is pretty much spent and barely cranks the car if at all. This would be the case with most of my cars that I own so I usually just disconnect the battery from the car to give it more life.
Batteries will also have some discharge even if they're not hooked up to anything.
Let a car battery sit in storage for some time and see what it does. It'll usually lose voltage enough to be noticeable from just sitting there. How the battery is built and it's internal structure determine how well it holds a charge.
Good luck.
That's .0105 amps and considering that there's approximately 600 cranking amps in the system of the battery, it's not worth mentioning.
Alternator diode will have some kind of leak down but it will be a minimal amount that should not hurt or draw that much to make a difference in the batteries loss.
All diodes do this and can't present a perfect blockage of voltage through it's junction. It's not possible.
Try removing all the relays if necessary and take another reading.
So you're still having issues with the battery dying in a short period of time?
I'll tell you that in 2-3 weeks, my battery in the Porsche is pretty much spent and barely cranks the car if at all. This would be the case with most of my cars that I own so I usually just disconnect the battery from the car to give it more life.
Batteries will also have some discharge even if they're not hooked up to anything.
Let a car battery sit in storage for some time and see what it does. It'll usually lose voltage enough to be noticeable from just sitting there. How the battery is built and it's internal structure determine how well it holds a charge.
Good luck.
09-28-2010, 11:11 AM
#13
Race Car
You want to keep the meter leads connected to the terminals BEFOrE you remove the negetive terminal. Meaning, connect the meter leads between the post and terminal on the battery, then remove the terminal. Reason being, is that if you have the terminal connected, and the draw is present, when you disconnect the negetive terminal you kill everything including the draw. then when you reconnect the circuit with the meter - it may not be there.
What is your battery voltage after letting it sit for a while disconnected and not on a charger?
What is your battery voltage after letting it sit for a while disconnected and not on a charger?
09-28-2010, 11:56 PM
#14
Try leaving the fully charged battery disconnected for 24 hrs to see if it still drains. Sometimes batteries develope an internal short. If the battery won't last more than a day, there's a pretty heavy load somewhere.
