What is a Yaw Sensor?
Vehicle stability control is nothing new, but the idea and function of stability control systems are being developed to achieve greater and greater feats. Once component at the heart of stability control systems is the yaw sensor. It measures angular change around the vertical axis of a vehicle. Sounds complicated, but it simply means yaw sensors measure which direction the vehicle is pointing. While it may not be abundantly clear why the vehicle needs to know which direction it is pointing, it all comes into perspective when the vehicle is placed on a roadway - especially around a slippery turn.
How do Yaw Sensors work?
Yaw sensors are the next step in a line of components designed to provide next-level performance and handling characteristics to even the most ordinary vehicles. They work in conjunction with the anti lock brake (ABS) and traction control (TC) systems to control wheels individually in order to provide the safest and most recoverable situation for the driver in the event that one or more wheels brakes traction. The yaw sensor measures inertia of the vehicle to determine at which angle the vehicle is turning, and this information is sent to various control modules for further analysis. In a skid, the ABS control module may notice the wheels slipping, and the yaw sensor will report which direction the vehicle is skidding, and these measurements will allow the ABS and TC control modules to take appropriate action to control the skid and recover the vehicle into the intended path. Also, the information from the yaw sensor can be used to prevent sliding or tipping during a turn by requesting the brakes remain locked open or intermittently pressed for individual wheels at specific points throughout the turn.
What are the symptoms of a bad Yaw Sensor?
As soon as any component of the stability control system fails, including the yaw sensor, the driver will receive a message that the stability control system is deactivated, inactive, or off. In many vehicles the TC and ABS lights may illuminate, and any advanced manufacturer specific handling and chassis control system warning lights will illuminate. If the sensor fails to send accurate information, the stability control systems may continue to function for a short while, but they will be deactivated due to unexpected performance when compared to other components of the stability and steering systems. The vehicle should remain generally driveable.