The Steering wheel angle sensor uses two sensors ( A-sensor and B-sensor ) to determine the direction of the rotation. The main components of each sensor are LED, photo transistor and slit plate. The slit plate, which has 45 holes, is installed between LED and photo transistor, and generates signals if slit plate rotates according to the steering wheel rotation. The sensor signals are generated by photo transistor which is driven whenever the light passes through the holes. The HECU detects operating speed and direction of the steering wheel by this input signal, and the signal is used to input signal for anti-roll control.
The HECU checks the CAN communcation lines for normal control and if a steering anlge sensor's message is not received for a certain period, this DTC is set.
Item
Detecting Condition
Possible cause
DTC Strategy
CAN message monitoring
Faulty Steering Angle Sensor(SAS)
Open or short in CAN communication line
Enable Conditions
When the steering anlge sensor's messages are not received for more than 0.5 second with a normal voltage condition
Fail Safe
Inhibit the ESP/DBC control and allow the ABS/EBD control.
The ESP/DBC warning lamp is activated.