Yaw Rate Sensor: Description and Operation
Anti-Lock Control - Traction Control - 4.2LCOMPONENT LOCATIONS - SHEET 1 OF 2
NOTE: LHD (left-hand drive) installation shown, RHD (right-hand drive) installation similar
COMPONENT LOCATIONS - SHEET 2 OF 2
NOTE: RHD (right-hand drive) installation shown, LHD (left-hand drive) installation similar
GENERAL
The anti-lock control - traction control system is based on the 4 channel Bosch 8.0 system and provides the following brake functions:
^ ARM (active roll mitigation).
^ ABS (anti-lock brake system).
^ CBC (corner brake control).
^ DSC.
^ EBD (electronic brake force distribution).
^ ETC (electronic traction control).
^ EBA (emergency brake assist).
^ EDC (engine drag-torque control).
^ HDC.
The system consists of the following components:
^ A DSC switch.
^ An HDC switch.
^ A stoplamp switch.
^ Four wheel speed sensors.
^ A yaw rate and lateral acceleration sensor.
^ A steering angle sensor.
^ Four warning indicators.
^ A HCU (hydraulic control unit) with attached ABS (anti-lock brake system) module.
YAW RATE AND LATERAL ACCELERATION SENSOR
Located under the center console, the yaw rate and lateral acceleration sensor provides two inputs to the ABS (anti-lock brake system) module, lateral acceleration and yaw rate, for DSC regulation. The sensor is isolated from body/chassis vibrations through its rubber mounting and secured to the transmission tunnel with 2 bolts.
When the ignition switch is in position 11, the yaw rate and lateral acceleration sensor receives an ignition power feed from the CJB (central junction box). For yaw rate, the sensor produces a reference signal of 2.5 volts and a linear yaw rate signal from 0.7 to 4.3 volts. For lateral acceleration, the sensor produces a linear signal from 0.5 to 4.5 volts. In addition to using the inputs for DSC regulation, the ABS (anti-lock brake system) module also broadcasts yaw rate and lateral acceleration values, on the high speed CAN (controller area network) bus, for use by other systems.
The ABS (anti-lock brake system) module monitors the yaw rate and lateral acceleration sensor for faults and can be interrogated using T4. If a fault is detected the ABS (anti-lock brake system) module stores a related fault code and sends a CAN (controller area network) signal to the instrument cluster to illuminate the DSC HDC and brake warning indicators. The instrument cluster also sounds a warning chime and displays a DSC fault message in the message center.