Looked around and can't find anything on the typical idle current drain, when the car is off. Right now I am at 480 ma @ 12V with the car turned off and no apparent devices on. Seems kind of high. I also read where some cars will go into standby mode after a period of time, but this was not in reference to the Mini, so I don't know if it applies.

Anyway the car suddenly failed to start. I am thinking it is probably the battery, because it is time (original 2003), but the way it went seemed weird. I went to start it, and it started to crank, like usual, then it stopped suddenly. The inside lights flickered at different intensities for quite awhile, like there was some electrical failure, heard some relay clicking on and off. So, I measured the voltage and it was in the 9 something range, but jumping around. Initially I figure one of the cells failed, but not completely. Pulled one of the post and it jumped to 12.5V. Thought maybe I had a high current drain. After measuring and finding it to be in the 300ma range, @ 9V, it didn't qualify as high current. And the new battery @ 480ma doesn't either, but I am concerned, that it will kill battery over time. It jump starts fine and acts normal when running (in the driveway).

Long post, for what is probably an old battery, but does anyone know what the idle current of a Mini is? Thanks

Jay

 

Definitely a bad battery (probably a cell gone bad) as most will fail well before the 6 years you got out of yours.
Not sure on the drain tho.

 

480 ma sounds like a lot. If it's more than 25-40 ma, after waiting for it to
reach standby mode (key off, don't open door or turn anything on or activate
motion sensor in the alarm if you have one, and wait 10-20 minutes),
something's pulling current that shouldn't.

 

Thanks guys. I was able to do some more testing today. Bigshot, I suspect you are right about the cell. Like you said I got 6 years out of it, when some aren't getting half that, so I count myself lucky. Cristo, you are correct. After letting it stand for awhile, it dropped to 13 ma. So it seems, nothing else is wrong. That's to bad, because I so enjoy troubleshooting electrical issues.

Thanks again
Jay