Circuit Description

EBCM triggers a yaw rate sensor test every 40 milliseconds and switches sensor into test mode. EBCM sends a test signal to sensor via test circuit. When test is run, measured yaw rate from sensor to EBCM must be 18-32 degrees per second. At standstill, the vehicle yaw rate is zero. Yaw rate signal at standstill is called offset. If calibration at standstill is not possible, a quick calibration during driving is done. Measured yaw rate is calibrated to a calculated reference yaw rate signal. Yaw rate sensor sensitivity is estimated by comparison of reference yaw rate and measured yaw rate during cornering. Steering angle centering is process by which EBCM calibrates steering sensor output so output reads zero when steering wheel is centered. PCS steering angle sensor centering process is performed manually.

DTC sets if one or more of the following conditions exist:

• Yaw rate sensor signal is out of range for 220-420 milliseconds.
• Yaw rate sensor signal at standstill, which is called offset, is outside allowed range of -8 to 8 degrees per second.
• Sensor sensitivity, which is estimated by comparing reference yaw rate and measured yaw rate during cornering, is outside a predetermined range.
• Yaw rate is changing at a rate greater than 6-23 degrees per second in 40 milliseconds.