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Discussion Starter #1
I have battery discharged and charger over night did nothing, it discharged even more by the morning. I have removed leads from battery and trying to see if there's some short circuit, measured resistance on the positive and negative leads and got 50.0 Om is that means i have short?

As i let the water pump leak it was leaking on the alternator and few other places, i had last Friday, battery light meaning battery is not getting charge anymore.

Also i guess ABS and Breaks light has to do with short because of leak as well.
 

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The best way to look for a short is to hook your ammeter up in series with the negative batter cable and start pulling fuses cooking for the drain to stop on the battery. If you pull a fuse and the drain goes away, repair that circuit. A typical computer controlled car can have anywhere between 5 milliamps to 125 milliamps.
 

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^^^^ +1

Measuring resistance across the batt cables is a 100% worthless test that tells you nothing.
 

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Discussion Starter #4
cjjames23 I am not saying i have short, but thanks for info on finding it.
I was just exploring possibility of short when charger failed to charge the battery overnight.

I believe measuring resistance on open circuit of the car shows you that you have short because it supposed to be zero, however i am not sure if 50 Om is bad enough or not?

Or is there other method?
 

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cjjames23 I am not saying i have short, but thanks for info on finding it.
I was just exploring possibility of short when charger failed to charge the battery overnight.

I believe measuring resistance on open circuit of the car shows you that you have short because it supposed to be zero, however i am not sure if 50 Om is bad enough or not?

Or is there other method?
Zero resistance would be perfect continuity. Measuring resistance between the positive and negative cables with them off of the battery will show an extremely high resistance due to having the voltage from the meter being forced to travel through all different types of resistors before getting back to the meter. If your battery isn't charging, I would suspect the battery to be at fault or the charger.
 

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Sounds like a bad battery to me unless your charger is dead. Not at all uncommon to get batteries that will not accept a charge.
 

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do you have access to a DC clip-on ammeter? Clip the ground wire.
It will tell you your drain with the key off - you can then do the fuse pull trick to find where your current is going.
 

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Discussion Starter #10 (Edited)
Have you charged disconnected battery?
Yap i did charged with my BatteryMinder and floated for like 3 days and showed about 12.5v after charge (i know its not a lot), however when i put it into the car in two days it was back to 1 (one) volt !!!

Car was just standing parked so i dont know how it drained, disconnected it again this morning and put on charge, and resistance today was 30 om with disconnected battery, i guess i need to look into this as no one here can tell me if that's too much or not.

mrbuj Battery is 2 years old at most, its AGM battery, however i seen on the sides some deformation, it could be due to 16v from alternator it could have been gradually increasing i have not measured it for a while so it could have overcharged it constantly for months.
Fot that calculator where do i get other values from i only know voltage.


Ocelot i dont have that yet, however i got amp meter in my multimeter is that the same say if i disconnect ground on battery and put it between ground on battery and ground wire ?
 

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I can't see the value of a resistance test but would surely recommend current draw test from ground lead to neg post as a valid test. I think given the overcharge and the results you have seen after charging it you may have cooked your battery. Have you load tested it?
 

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I have a couple. The Cen-Tech 500 amp carbon pile is a decent one for under a $100. But you can get it done at a lot of auto parts places and Sears used to do it free as well
 

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Yap i did charged with my BatteryMinder and floated for like 3 days and showed about 12.5v after charge (i know its not a lot), however when i put it into the car in two days it was back to 1 (one) volt !!!

...i seen on the sides some deformation, it could be due to 16v from alternator it could have been gradually increasing i have not measured it for a while so it could have overcharged it constantly for months.
Fot that calculator where do i get other values from i only know voltage.
QUOTE]

1v, deformation = cooked
 

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Take the battery to Advanced or Autozone or NAPA. They all test batteries for no charge (no pun intended, but dang - it's one of my better ones!).
 

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Discussion Starter #19
Whats no charge test? It does charge because it charged from 7v to 12.5v few days ago.

In AutoZones here in LA are bunch of Interns good if they know how to charge the battery..., anyway i cannot drive carry it there its bit too heavy, i try some tests at home for now.
 
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