I don't understand why the system cares whether the oil or fluid is fresh or used-up. It must have been a costly sensor with the ability to distinguish between new and old fluids. It baffles me why a machine would detect both fresh and stale fluid
. Regarding the air-to-fuel ratio, fluid level (such as the amount of gas in your tank), and transfer case fluid level, it makes sense. Therefore, it appears that this calibration is unnecessary. In the event that you are an X3 designer, please explain the logic.