1st Gen R53 Cooper S Battery Light Illuminated,....Alternator and Battery test GOOD

05 MCS w/ 81k, bought it Nov 2013 and been running great up to this point.

Had a similar experience as panaphobic, here: http://www.motoringalliance.com/forums/cooper-s/11024-battery-light-no-power-steering.html#axzz2w0DWd5kT

Battery Measurements: meter across +/- battery terminals

no connection, out of the car: 12.67V
Connected, car idling: 11.8V
Connected, car @2500rpm: 11.54V

Pulled the alternator, looked original, and it tested GOOD according to Autozone test bench. Battery tested GOOD too. I've had problems with false negatives from auto zone in the past so purchased a new alternator from WMW for good measure and peace of mind -- keep the old as a backup.

With the new alternator installed and GOOD battery the battery light stayed illuminated. ugh.

Started tracing through the connections; jump post connection ok, under bonnet fuse box connection ok. all the grounds I could find seemed ok.

Turned my attention to PS pump wondering if it was causing a load on the battery. unplugged it. bamm battery light off. plug it back in and battery light comes back on again. Does this mean the PS pump is gone?? :frown2: The crazy thing is maybe the battery isn't taking a charge -- even thought it's GOOD -- and when the PS pump is plugged in the voltage drop is too low throwing the battery light. My logic there is metering the battery while the car is running can watch the voltages tick off every few seconds going lower , lower , lower to a point with car running a good 15-20min, turning it off and disconnecting the battery the voltage reads 12.2V. IOW it isn't taking a charge although its a GOOD battery.:confused5:

Anyone else have a similar experience? Maybe just take a bath ($$) and try another battery?

Thanks for the help!

 

Thanks for the support!

Damper looks and feels ok - can't spin/rotate the metal piece with the belt removed.

I believe autozone did load test it via a load meter (handheld); maybe its different with the battery connected in the car. Or I assumed this was a load test. I didn't think about this yesterday but have a 98 900S saab w/ same exact battery (i think). I'll pull it out and see if that resolves the problem. btw, saab has 252k and runs like a charm... not near as fun to drive though.

I'll update later after checking that out tonight.

 

ok here's my findings...

using the same spec'd saab battery (batt #2) had the same results as the GOOD battery (batt #1) from above. battery light illuminated, reduced voltage below 12V across the battier terminals.

I retraced the connections and fuses in box 3 and 2 and found F39 Fuse box 2 open. pulled it put a spare in and blown again. this is alternator and PSP fuse.

I'm thinking its the PSP. I could smell PS fluid for a few seconds it seems before KOEO and checking F39 again.

I'll call mini dealer tomorrow and ask about the PSP replacement.