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Chad535
10-02-2005, 11:12 PM
hi all, it's been a while since i was here for the last time so greetings to all of you fellas.
Now since my car refuses to start and i couldn't verify if it is the battery or alternator i would like to make sure that i am prepared by having all the necessary info so i would appreciate if anyone could give me the battery capacity and other specs.

Chad 535/89 Auto

shogun
10-03-2005, 12:51 AM
I tried OBC test #9 before but still prefer to measure the voltage the old sure way because my OBC for some reason measures a voltage 0.2V lower than a calibrated DMM. (=digital multi meter)

Find a digital multimeter and stick the probe into the cigarette lighter socket in the center console.

The following are the detail figures I use for my own evaluation:
With key out of ignition switch, should see 12.4V or above. 12.0 V is getting low.
With key inserted and turned to position 2 (don't start car), should see 12.0V or more. 11.6V would be too low.
Crank car, catch the lowest voltage reading during that couple of seconds. Should see 10.0V or above. 9.5V would be marginal.
The above just consider the health of battery itself.
Car running at 1500 RPM or more, should see 13.7 to 14.3V, 13.6V or below means the charging system is weak.

Qsilver7
10-03-2005, 10:42 AM
hi all, it's been a while since i was here for the last time so greetings to all of you fellas.
Now since my car refuses to start and i couldn't verify if it is the battery or alternator i would like to make sure that i am prepared by having all the necessary info so i would appreciate if anyone could give me the battery capacity and other specs.

Chad 535/89 Auto
Here's a link with info and pics if you need to replace the battery: http://forums.bimmerforums.com/forum/showpost.php?p=4912217&postcount=4