Aloha - Question, not a gripe. In September, we noticed that my friend's stock MINI battery's eye was not glowing green ('05 Cooper w/CVT). There was no starter drag or symptoms of low battery other than low battery voltage (tested 12.75 - 13.0 at rest).
By date, battery was 3 years/4 months old. Battery replaced w/non MINI unit.
Last week, check engine light came on. Thinking it was voltage fluctuation or emissions related, I cleaned and reinstalled all plug wires and checked gas cap. Light went out for 3 days then reappeared.
MINI sent to dealer for diagnosis. Per dealer "charged battery, performed short test, CVT transmission ratio actuator fault. Can be caused by under voltage." Dealer performed CVT re-adaption and road tested car - light is now out.
I have two MINIs, one of which is also an '05 CVT. Batteries have gone dead on the auto then been replaced w/no check engine light coming on.
I thought I would ask you MINI gurus if this condition could have been caused by low voltage or perhaps indicative of something else?
Mahalo!

 

It was most likely low voltage.
Sometimes (not always) disconnecting the battery can cause a module in the car (engine, transmission, etc.) to lose it's adaptation values. Usually, the longer the battery is disconnected, the greater the chance.

 

Thanks for the reply - no problems so far after readaptation, so will continue to monitor.