Yaw Rate Sensor
A sensor that measures the vehicle's rotational velocity around its vertical axis to help control vehicle stability.
A yaw rate sensor is a gyroscopic sensor used in electronic stability control (ESC) systems. It measures the vehicle's rotational velocity around its vertical axis—a motion known as yaw (spinning or swerving)—to determine if the car is slipping or sliding.
The sensor is typically mounted near the vehicle's center of gravity (often under the center console or rear seats). It detects when the car is rotating faster or slower than the steering wheel angle indicates, which happens during understeer (plowing straight) or oversteering (spinning out).
When the stability control computer detects a mismatch between steering angle and yaw rate, it immediately intervenes. The system can apply individual wheel brakes (such as braking the outer front wheel during oversteer) and reduce engine power to help the driver regain control.
If the yaw rate sensor fails, the ESC system will disable itself and illuminate a warning light on the dashboard. Diagnosing a bad sensor involves checking its live G-force and yaw data stream using a diagnostic scanner.