blink962

hi guys
after loooots of time,i found that my alternator positive wire is draining my batterie when connected to alternator..
there's a draw of 230ma and sometime drop to 160ma and goes back to 230ma.
my battery is relocated to trunk with a 0\2 big wire.the battery is charging.i didnt upgrade my alternator wire.i dont know if it could be related?
alternator has been tested good by a shop..and i also tested on a another battery (not on car) and theré's no current draw.
so why my alternator drain 230ma when i conmect the positive wire on it? thanks!!

oth

This is way beyond my expertise, and you may get better answers in the "Under the Hood" forum,
but IIRC a draw like that is a symptom of a bad alternator diode.

_valtsu_

Hi

If you tested it with another battery and there was no current draw, then only thing what comes to my mind is, that current drain goes thru that small connector where 4 small cables are connected. Try to take it off from alternator and see if current draw disapears.

engifineer

Seeing as how the positive battery wire is connected to the positive alternator wire, depending on how you are testing you may just be seeing the parasitic draw from the ECU. When you disconnect power to the ECU and then re-apply it, you will see a higher draw for a short time, usually stepping down, then dropping yet again when it goes into "sleep" mode. This happens also after you turn the car off too. So make sure you get hooked up and let it sit for a while and see what it eventually gets down to. I believe that 200 mA is common right after power up/power down and then it drops off from there (ECU is booting up, then doing some stuff, then idles, then goes to sleep). After that, depending on car, 30mA to 60mA is somewhat normal. Some cars are higher.

Chuck S

There's always power being drawn. Otherwise the alarm and electric door locks would not operate nor would the radio retain its memory.

Not sure if 230 ma is a decent number. That's almost a quarter amp so every 24 hours sucks about 6 amp hours from the battery. At 160 it sucks about 4. I doubt there's more than 35 or 40 useful amp hours in the battery before the voltage drops below the point you can start the car.

-- Chuck