Hello,
I have done tons of research here and want to make sure it is just my alternator before I replace it. I had all the symptoms of a MINI alternator failure while driving. ABS , Traction control, Battery lights on, Lost Power steering, very little power in drive. Shut the car off and I would not start.
I let the car sit over night and got my Multimeter. Battery at only 12.03 volts. Cleaned the battery terminals, battery ground and engine ground wire at mount. The car started with that voltage but running the voltage dropped down to 9.6 v. Pending code P0562 (System low voltage) I only ran it for a few seconds with that low voltage before it started acting up. As the battery was 5 years old I purchased a new one and needed to run the car to get it behind my house after a AAA tow. The new battery started the car and the voltage began to drop while running. 12.2 volts.. 11.9 volts.. NO lights on dash though. I am assuming it would run until the voltage got too low and the same would start all over again.

Question: If the Alternator had failed wouldn't the BATTERY light be on the dash when the car was running with the new battery indicating the system is not charging at the expected 13 -14 volts?
FYI- The battery light does work in the run position before start up, the belt is intact and driving the pulleys. No burning rubber smells , no electrical smells etc.
Thanks for any help
Tom

2006 Mini Cooper S 104,000 miles.

 

I am having issues with electrics that are different, but after swapping out the battery I noticed the fusable link setup near the battery in the back was corroded as crap since the old battery did not have the plug in the offside of the vent tube, everything had a rust dust haze on it. I am hoping that by taking it all apart tomorrow night, will fix my issues.

Just tossing it out because I am figuring the alternator comes back to the battery and from there moved throuhg the car. (I think there are two paths for the voltage, one gauges, one the engine...or something like that.

As always, I offer a money back guaranty.

 

Thanks HRM for your reply,
Any insight explaining the issue and how the system works in the MINI and how this is possible?? Being the S model the wiring is different, 3 wires at the plug vs. 2 on the non -S per Bentleys schematic . The low voltage is at every Positive point on the car, not just the battery, while the car is running.

I am writing the rest of this to help someone else maybe.
Evidently it is possible for this to happen as i replace the alternator today and the issue was resolved. ( DENSO reman from rock auto). I checked all Fuses, F39 in particular. I checked continuity from B+ on alt to ground to make sure it was zero and it was not shorting as there is no fuse that I can see from the B+ on Alt to a main positive hub or fuse block. I checked continuity between B+ on alt to battery + Post to made sure it was there and it was not an issue of the wire being broken.
The thing is with these car is you have to pull everything apart to get to the Alt to test these leads.
I ran the car again after cleaning more terminals and junctions, Alternator did make a slight whining noise and i smelled burning electronic smell with my fat nose right up against the Alternator. I disconnected the 3 wire plug and the noise and smell went away. I felt confident that it was just the alternator . Old alt did move freely.Swapped it out , tested it, and the 14.27 volts were back. Evidently something was up regulator.

One more thing... the alternator stopped working after i hit a very deep pothole on the front right , right where the alternator is located. Maybe the brushes were so worn that they moved out of place.

Thanks for all other posted here that helped in instructing on the physical removal of the part. ( service mode, etc) I will say i used a 200m M80 1.25 threaded rod and not a 100 mm bolt to get in service mode, I only removed the right crush tube and every hinged out of the way quit nicely.

 

I have a similar issue and bought a remanned Bosch alternator on rock auto. Everything else about my current alternator is fine, in fact it looks like it was replaced recently. If these voltage regulators go out this quickly, is there any known place that will sell just the voltage regulator to us without having to buy a complete alternator?

 

Well I should have tinkered around my engine bay a bit before assuming that my alternator was to blame. I found that the charging issue was due to a loose connection to the engine grounding wire that connects from the top motor mount to the body. After tightening that up, my MINI starts and runs perfectly! Also, checking the voltage from my BT OBDII device shows that it's charging at 14v, when it previously was only showing <12v while running.

Check all your grounding points!