The Intelligent Battery Sensor (IBS) is one of things that has been bugging me since I am not 100% clear on the details of how it works.
The TIS says that you should charge from the terminals under the hood and not bypass the IBS but the TIS also has instructions about charging batteries when removed from the car.
Until I can determine if it's 100% safe to charge directly I always charge from the terminals under the hod.
Straight lines are for fast cars...turns are for fast drivers
'04 M3 - track
'06 650i Cab - daily driver
'02 Highlander - kid hauler
'01 330Ci - winter beater