Calculation of Vehicle Position
WARNING: This page is about a different car, the 2011 Honda Insight and 2010 Honda Insight. However, it is still accessible from the selected car via links, so may be relevant.
The audio-navigation unit calculates the vehicle position (the driving direction and the current position) by receiving the directional change signals from the yaw rate sensor and the travel distance signals from the PCMs vehicle speed pulse (VSP) signal.