A sensor includes a detector configured to sense a parameter, at least one test circuit configured to detect a respective fault condition of the sensor and generate a fault signal in response to detecting the fault condition, a checker configured to test the at least one test circuit to determine the operational status of the at least one test circuit, and an output signal generator, coupled to receive the sensed parameter, the fault signal, and the operational status of the at least one test circuit. The output signal generator is configured to generate an output signal of the sensor to communicate the sensed parameter and the operational status of the at least one test circuit.