Abstract: A level of fluid in a container is determined as is a capacitance associated with the fluid. The capacitance and level are used to determine a concentration of ethanol in the fluid.

Abstract: A method for determining engine oil contamination includes determining an engine run time and an oil temperature. Based on the oil temperature, a cold event counter is increased by one or a hot event duration value is set equal to the run time of the engine. The cold event counter and the hot event duration value is then used to predict when the engine oil has been contaminated by water and fuel.

Abstract: A system for automatically resetting an oil condition alarm light after an oil change includes an in-vehicle digital processing apparatus electrically coupled to a warning lamp and to an oil sensor installed in an engine oil pan. The digital processing apparatus further includes a warning lamp reset module to automatically reset the oil sensor following an oil change, based on an oil parameter difference value.

Abstract: An algorithm by which a time normalized oil condition trend (OCT) is developed. During engine off periods, while the engine is cooling, the vehicle's main computer program implements the trend algorithm according to the present invention by which engine oil conductivity (oil sensor output voltage) and temperature data are obtained in a specified temperature range, and are then input into a cool down equation to determine its coefficients using nonlinear regression. This cool down equation models oil conductivity as a function of temperature and is used at a specified time during an engine-on period to calculate an OCT point. Collectively, these OCT points determine the oil condition trend that is analyzed by a procedure called from the vehicle's main computer program to determine when an oil change is necessary.