Comprehensive Component Monitoring
Comprehensive Component MonitoringSensors that can affect emissions or used to monitor or enable monitors for other components/ systems are monitored for open circuit, short to ground and/ or short to battery voltage, using high and low voltage signal limits.
Actuators that can affect emissions or used to monitor or enable monitors for other components/systems are monitored by power stage checks for open circuit, short to ground and/ or short to battery voltage.
For some of the sensors and actuators, rationality and/or functional checks are included to ensure proper operation of the components. This is accomplished through the use of a model or other sensor inputs. If a component does not function as expected or the integrity is in question (values are not with-in a threshold) it is considered out of range or not rational.
Electrical checks for Sensor signals
Sensor signals out of a defined range are regarded as circuit malfunctions shorted to battery plus, shorted to ground or open circuit.
Electrical checks for Actuators
The output stages are integrated in manufacturer specific IC's. The IC has a binary diagnostic line (e.g. ATIC 39). Invalid actuator output signals at power stage are regarded as circuit malfunctions shorted to battery plus, shorted to ground or open circuit. If the control line of one stage has a different activation signal than the output line, the logic circuit inside the IC detects a malfunction. The logic circuit within the IC can separate the type of fault to a short circuit to minus, an open line, or a short circuit to plus. The check result will be sent to the ECM via diagnosis line.