What's killing my Battary in 2 hours ?

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08PathPounder
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What's killing my Battary in 2 hours ?

Postby 08PathPounder » Fri Sep 11, 2015 6:10 am

Fully charged after being jumped or trickle charged over night, something is killing my battery within 2.5 hours. Driving me insane. I pulled the battery and trickle charged it over night let it sit for a few hours and put a load test on it and it says it's fine. Waited a few more hours put a load test on it and the thing is still fine. So i know it's not the battery, something is draining it and FAST . Any ideas ?


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disallow
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Postby disallow » Fri Sep 11, 2015 7:13 am

I'd do a load test on your fuses to see where the power is going.

Mulitmeter measuring load in mA between the positive batter cable and the post to see what the pull on the battery is. Then start pulling the fuses one at a time and observe when the pull drops to near 0. That will be your culprit.

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Postby 08PathPounder » Fri Sep 11, 2015 9:03 am

disallow wrote:I'd do a load test on your fuses to see where the power is going.

Mulitmeter measuring load in mA between the positive batter cable and the post to see what the pull on the battery is. Then start pulling the fuses one at a time and observe when the pull drops to near 0. That will be your culprit.
Thanks for the quick response, going to attempt this between rain showers today.
Would you recommend start with fuses under the hood or under the dash?

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Postby eieio » Fri Sep 11, 2015 9:13 am

what is the history of your battery, how old?
not all batteries that seem to charge & load test OK are good
also, what is your charging system voltage output

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Postby 08PathPounder » Fri Sep 11, 2015 9:48 am

eieio wrote:what is the history of your battery, how old?
not all batteries that seem to charge & load test OK are good
also, what is your charging system voltage output
Brand new when I bought pathy in Feb, and after I start the car and it runs for a bit it's in the middle of the "bar of margin" on the dummy gauge in the dash, typically in the top right corner of the battery symbol when running.
I'll do a voltage test as soon as I can it's raining at the moment. I got chased in after pulling all the fuses under the hood in both boxes behind the battery it's self and the numbers never even flinched on the meter.... Driving me crazy. I unhooked my subwoofer and amp completely and still no change... My guess is it has to be something that has a constant 12v running to it due to the fact it dies with key out of ignition and off... Or is that not true?

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Postby 08PathPounder » Fri Sep 11, 2015 10:17 am

14.3 dcv when started and then levels out in the 13's

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Postby eieio » Fri Sep 11, 2015 11:58 am

charging rate is good
do you have a different battery that you might be able to swap in?
i'm suspecting the battery

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Postby 08PathPounder » Fri Sep 11, 2015 12:33 pm

eieio wrote:charging rate is good
do you have a different battery that you might be able to swap in?
i'm suspecting the battery
I wish I did, maybe advanced will let me swap one real quick? Doubt it .... But In the last hour of sitting ( 2pm -3pm ) with the motor off since 1:45 ish pm the voltage went from 12.79 to 12.69. I'm not sure if this typical or if it will level out at a certain point? Or if it will keep diving.... The last thing I need is it taking a crap when running errands or leaving work...

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Postby smj999smj » Fri Sep 11, 2015 12:54 pm

You should really find out what the parasitic draw is, which would require an ampmeter. Typically, 50 milliamps or less is considered okay. I have an OTC parasitic draw tester which works great. The "poor man's" draw tester is using a 12 volt test light placed in-line between the negative battery cable and the negative battery post. Make sure everything is turned off and if you have to have the driver's door open, disable the door switch. Let the vehicle sit for a minute or two and see if the test light is illuminated. Remove fusible links and/or fuses until the test light goes out to identify the circuit. Once you identify the circuit, you will need a wiring diagram to find out what's on that circuit. For a large draw, I would start at removing the fusible link for the alternator; sometimes they will short internally and that will kill a battery in no time!

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Postby 08PathPounder » Fri Sep 11, 2015 1:52 pm

Let me just say thank you to everyone and their input, I genuinely appreciate the advice and things mentioned, if it wasn't for this forum my ride wouldn't be what it is. You guys are awesome.

smj999smj wrote:You should really find out what the parasitic draw is, which would require an ampmeter. Typically, 50 milliamps or less is considered okay. I have an OTC parasitic draw tester which works great. The "poor man's" draw tester is using a 12 volt test light placed in-line between the negative battery cable and the negative battery post. Make sure everything is turned off and if you have to have the driver's door open, disable the door switch. Let the vehicle sit for a minute or two and see if the test light is illuminated. Remove fusible links and/or fuses until the test light goes out to identify the circuit. Once you identify the circuit, you will need a wiring diagram to find out what's on that circuit. For a large draw, I would start at removing the fusible link for the alternator; sometimes they will short internally and that will kill a battery in no time!
Does this include pulling relays as well? I had the multimeter in mA and had the prongs weged into the battery terminals when i pulled the fuses one by one...nothing changed than again I could have been wrong with what I was doing ? Idk .. I'm going to try the 12v dummy light at the ground and start pulling fuses that are under the hood.

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disallow
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Postby disallow » Sat Sep 12, 2015 6:53 am

Did you disconnect the positive battery cable? The multimeter goes between the cable and and battery terminal to measure the mA draw.

What value of you get when when multimeter is set at 50 mA?

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Postby smj999smj » Sat Sep 12, 2015 5:09 pm

Don't be concerned with the relays right now. Relays are powered through fuses.

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Postby 08PathPounder » Mon Sep 14, 2015 5:30 am

Had a busy Sunday riding the Harley didn't do much trouble shooting on the pathy... With that said, I noticed how loose my ground terminal was on the post even when tightened to the point of no more thread I could rotate it on the post with no problem but could not slide it off. So I took a set of vice grips and lightly but surely clamped down and pinched the opening a "little" tighter. It now gets tight as intended and works like it's supposed to. After doing this, my killing suddenly stopped. Hasn't died in two days. Could this seriously be the issue?
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eieio
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Postby eieio » Mon Sep 14, 2015 6:53 am

08PathPounder wrote: I noticed how loose my ground terminal was on the post even when tightened to the point of no more thread I could rotate it on the post with no problem but could not slide it off. So I took a set of vice grips and lightly but surely clamped down and pinched the opening a "little" tighter. It now gets tight as intended and works like it's supposed to. After doing this, my killing suddenly stopped. Hasn't died in two days. Could this seriously be the issue?
not a bit surprised, it sounded battery/battery related from the "get-go"

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Postby 08PathPounder » Wed Sep 23, 2015 8:58 am

It's been a few days and everything seems fine. Just want to say thank you to the forum and the people involved that are here to help. Yous are awesome and I appreciate what you guys do. Thanks again.


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