Application of failure detection filters to the diagnosis of sensor and actuator failures in electronically controlled engines

The authors discuss the application of detection filters to the diagnosis of sensor and actuator failures in automotive control systems. The detection filter is the embodiment of a model-based failure detection and isolation (FDI) methodology, which utilizes analytical redundancy within a dynamical system (e.g. engine/controller) to isolate the cause and location of abnormal behavior (i.e. failures). The authors present the philosophy and essential features of FDI theory and describe the practical application of the method to the diagnosis of faults in some key sensors in an electronically controlled internal combustion engine.