Vehicle Speed Pulse (VSP) Sensor
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2004 Honda Odyssey, 2003 Honda Odyssey, 2002 Honda Odyssey, 2001 Honda Odyssey, and 2000 Honda Odyssey. However, it is still accessible from the selected car via links, so may be relevant.
The vehicle speed pulse (VSP) sensor is driven by the differential gear (2000-01) or the PCM (2002-04). For every revolution of the wheel, a four-pulse signal is sent to the navigation unit. The VSP outputs the distance signal by turning the navigation unit's sensor power on and off.