Abstract: A method for monitoring the reductant quantity in a reservoir method is provided. The reductant is stored within the reservoir for use within an exhaust gas treatment system of a vehicle, and the reservoir comprises an acoustic sensor disposed within the reductant and capable of generating signals relating to the volume of reductant within the reservoir. The method includes generating a first signal for validation after a system wakeup, conducting a wakeup validation using a wakeup condition, wherein the wakeup condition includes determining if the first signal is within a first accuracy threshold relative to a validated signal generated during the previous operating cycle; and conducting a secondary validation for a signal generated after the first signal using one or more secondary validation conditions. The method can further comprise conducting one or more subsequent validations for one or more signals generated after the first signal.

Abstract: A method for monitoring the reductant quantity in a reservoir method is provided. The reductant is stored within the reservoir for use within an exhaust gas treatment system of a vehicle, and the reservoir comprises an acoustic sensor disposed within the reductant and capable of generating signals relating to the volume of reductant within the reservoir. The method includes generating a first signal for validation after a system wakeup, conducting a wakeup validation using a wakeup condition, wherein the wakeup condition includes determining if the first signal is within a first accuracy threshold relative to a validated signal generated during the previous operating cycle; and conducting a secondary validation for a signal generated after the first signal using one or more secondary validation conditions. The method can further comprise conducting one or more subsequent validations for one or more signals generated after the first signal.