battery drain reading
TaurusKing
08-31-2016, 06:29 PM
Ok, my mind's gone blank. Checking my battery for parasite drain, get a reading of 5.6 on the 200ma scale. Forgot had to arm the theft system. Is this alright? Thanks
65comet
08-31-2016, 08:53 PM
I don't know about that reading, but a common problem is with the trunk switch not turning off the trunk light. If you have the fold down seats, leave one down and see if the light is off. If your seats don't go down, pull the bulb then check your meter.
shorod
08-31-2016, 09:58 PM
If you're reading a drain of 5.6 mA, that's well below what's acceptable. Acceptable is more like 70 mA once the vehicle has gone to "sleep." A drain of only 5.6 mA would require several weeks of sitting to drain an otherwise charged and healthy car battery.
-Rod
-Rod
TaurusKing
08-31-2016, 11:16 PM
Thanks, it was down to .2 when i checked it again. Car sat the weekend, Monday morn dead. Charged it up, no drive, 24 hrs later dead again. Gravity test 3 cells good, three lower end good. Battery is 3 - 3 1/2 yrs old, have to check my book. Maybe that's all there is nowadays for a regular nothing special wet cell battery. Thanks again, I'll post end result.
shorod
09-01-2016, 06:57 AM
Was that 0.2 mA or 0.2 A that you measured? What tool are you using to measure the current draw, and how do you have it installed? Was it installed the entire time between when you measured the 5.6 mA and the 0.2? Was the battery already dead when you measured the 0.2?
The symptoms sure make it sound like either the cables are really loose or corroded or your battery is shot.
-Rod
The symptoms sure make it sound like either the cables are really loose or corroded or your battery is shot.
-Rod
TaurusKing
09-04-2016, 11:22 PM
All ma readings. Digital multimeter hooked thru negative cable, left hooked at least 1.5 hours. Started at 5.6ma, then 3.6, then 2.2, ended at the lowest#. First three #'s were within 20 or so mins. Battery was fully charged for all testing including gravity. Looked up purchase date of battery , way off on that one, will be 5 years Sept 16. Had it tested at store where purchased, it passed their testing. Has been starting since, morning and evening. I guess it's the old wait and see when, always carry cables in all our cars. Thanks
shorod
09-05-2016, 02:41 PM
A measured reading of 0.2 mA is in the noise, and definitely not enough to cause a healthy battery to discharge within several weeks.
I'd be budgeting for a new battery if I were you....
-Rod
I'd be budgeting for a new battery if I were you....
-Rod
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