Vehicle Speed Pulse
WARNING: This page is about a different car, the 2008 Honda Pilot, 2007 Honda Pilot, and 2006 Honda Pilot. However, it is still accessible from the selected car via links, so may be relevant.
The vehicle speed pulse is produced by the PCM. The PCM receives a signal from the countershaft speed sensor, then it processes the signal and transmits it to the navigation unit speedometer (F-CAN) and other systems.