12 volt reading when either positive or neg. battery terminal is disconnected

dodge
batteries
spirit

#1

my new battery when dead after 2-3 weeks in the garage. the system is charging at 14.2 volts,but when i checked for a drain the amp meter was at 100ma,and either terminal disconnected at the battery reads battery voltage.do i have a bad ground or is power bleeding or feeding into another circuit?When i disconnect the ip connector my amps go to zero but my voltage is still at 12.volts.Or near the battery there is a black bullet connector that feeds a variety of fusible links-if i disconnect that my voltage also goes to zero? any ideas?


#2

Max draw on a battery is 50 milliamp. Anything over that will drain a batteery. Not quite sure what you’re doing with volts, amps but I would leave your amp meter hooked up and start pulling fuses until your amperage draw goes below .050. Not quite sure if you said you pulled a battery cable while it’s running. If so don’t do that. It could send a voltage spike to the computer that would fry it.


#3

Can you describe your technique for measuring what is know as a parasitic draw? many people get confused with setup when they try and measure amps.


#4

if i pull my dome light fuse my amps go to zero,if i do a voltage test across the fuse it reads 0 volts. my concern is when i remove either battery terminal when car is not running the voltage is 12 volts -i beleive if i fix the 12 v problem i will fix the draw-something is feeding back into the circuit or i have lost a ground-but everything works on the car?


#5

I want to know how you have your meter hooked up (when measuring amps).You need to stop the practice of removing the battery cable with the car running, this procedure won’t give you any usable data anyway. Your standing battery voltage should be above 12 volts also. This low standing voltage indicates a low charge on the battery. There are set ways to do electrical diagnosis, you can’t make up your own ways and expect people to be able to unravel what you are doing, you deviate and you are on your own.


#6

Where are you measuring the 12V when you pull a battery cable? I.e. The Voltage of what is 12V? Where exactly are you putting the meter leads? Or are you looking at a dash gauge?

Just for clarity, 12V basically just tells you about potential energy. It doesn’t tell you that any energy is flowing anywhere.


#7

Oldschool: “You need to stop the practice of removing the battery cable with the car running”

OP: “my concern is when i remove either battery terminal when car is not running”


#8

I took it as implied that he was also removing the cable while the car was running. do you have anything to add that could help the OP?


#9

if you have a 12v battery and disconnect the terminal with car not not running you should have 0 volts.im putting my volt meter one lead on batt. terminal and the other on the cable end thus 12v. again car is not running!either terminal shows 12v.test your car at home and it will read 0 volts!i feel like i have a bad ground or power source bleeding into another circuit?