Functional description

The sensor is supplied with voltage from terminal 15 ON. The sensor element requires an operating temperature of approximately 300 °C. The electronics in the AUC sensor control the clocking of the heater voltage (depending on the nominal and actual temperature). The AUC sensor has reached its operating readiness after 30 seconds and responds to ambient air changes.

The automatic air recirculation control sensor converts the detected air quality (also referred as air grade) into an electrical signal. To simplify processing of the information, the air quality in divided into 10 stages:

• Stages 0 to 10 (clean to severely contaminated)

F0x, F1x: The AUC sensor sends the corresponding level as a digital signal on the LIN bus to the junction box electronics (JBE). The junction box electronics (JBE) send the digital signal on the CAN bus to the IHKA control unit.

F15, F16, F4x, F5x, I01, I12: The automatic air recirculation control sensor transmits the corresponding stage as a pulse-width modulated signal to the Body Domain Controller (BDC). The Body Domain Controller (BDC) transmits the digital signal on the CAN bus to the IHKA control unit.

F2x, F3x: The automatic air recirculation control sensor transmits the corresponding stage as a pulse-width modulated signal to the front electronic module (FEM). The front electronic module (FEM) transmits the digital signal on the CAN-Bus to the IHKA control unit.

The information is updated every second according to the internal measuring interval.

Courtesy of BMW OF NORTH AMERICA, INC.