Systems and methods for selective catalytic reduction (SCR) multipoint diagnosis

Systems and methods for diagnosing an exhaust aftertreatment system are provided. A controller determines, for each sensor of a plurality of sensors, one or more performance parameters based on measurement data obtained from the sensor that is indicative of a performance of the sensor or a component of the exhaust aftertreatment system. The controller determines, for each performance parameter, a corresponding degradation level indicator indicative of a performance degradation of the corresponding sensor or the corresponding component of the exhaust aftertreatment system. The controller can determine, for each degradation level indicator, a corresponding diagnosis threshold value for detecting an operational state of the corresponding sensor or the corresponding component of the exhaust aftertreatment system. The controller can determine a multipoint diagnosis threshold value based on the diagnosis threshold values, and determine an operational state of the aftertreatment system using the multipoint diagnosis threshold value.