Steering Wheel Angle Speed Sensor: Description

GENERAL DATA 

The steering angle speed sensor detects the angle of the steering wheel in order to which direction a user chooses.

MEASURING PRINCIPLE 

A non contact, analog angle sensor carrying out absolute measuring by the use of the Anisotropic-Magneto-Resistive effect (AMR). Measuring of the absolute angle by means of a toothed measuring gear with magnetic properties in combination with different ratios. Corresponding AMR elements that change their electrical resistance according to the magnetic field direction detect the angle position of the measuring gears. A micro-controller decodes the measured voltage signals after A/D converting with the help of a mathematical function. Output of the digital angle value and velocity via CAN-interface.

SPECIFICATION 

CIRCUIT DIAGRAM ( STEERING WHEEL SPEED ANGLE SENSOR) 

Fig 1: Circuit Diagram - (Steering Wheel Speed Angle Sensor)

Courtesy of HYUNDAI MOTOR CO.

STEERING ANGLE SENSOR (SAS) CALIBRATION 

1. PURPOSE OF calibration
   • On vehicle control, an ESC analyzes the intention of the driver.
   • An ESC recognizes a steering angle which a driver rotates through the steering angle sensor.
   • A steering angle sensor used in ESC adjusts 0° setting of steering wheel through K-line or CAN communication.
2. STEERING ANGLE SENSOR (SAS) CALIBRATION METHOD
   Fig 2: Identifying Steering Angle Sensor (SAS) Calibration Method

   Courtesy of HYUNDAI MOTOR CO.
   1. Align the wheel to the straight line, (steering wheel < ± 5°)

      ex) Perform the wheel alignment first.

      Align the wheel to the straight line.

      A driver moves the vehicle to the front and back about 5 meters twice or three times.

   2. Connect Scan tool to the vehicle.
   3. Select Brake system.
   4. Select Steering angle sensor (SAS) calibration.
      Fig 3: Scan Tool Display - HYUNDAI VEHICLE DIAGNOSIS

      Courtesy of HYUNDAI MOTOR CO.
   5. Perform the Steering angle sensor (SAS) calibration.
      Fig 4: Scan Tool Display - STEERING ANGLE SENSOR

      Courtesy of HYUNDAI MOTOR CO.
   6. Perform the procedure continuously.
      Fig 5: Scan Tool Display - STEERING ANGLE SENSOR PROCEDURE

      Courtesy of HYUNDAI MOTOR CO.
   7. The procedure is finished. Push the "ESC" key.
      Fig 6: Scan Tool Display - ESC PROCEDURE

      Courtesy of HYUNDAI MOTOR CO.
   8. Scanner OFF.
   9. Remove the scanner from the vehicle.
   10. Confirm the Steering angle sensor (SAS) calibration as driving the vehicle. (turn left once, turn right once)