Instrument Cluster: Gauges: Speedometer
WARNING: This page is about a different car, the 2004 Mercury Mountaineer and 2004 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.
The instrument cluster receives the vehicle speed sensor (VSS) signal from the powertrain control module (PCM) through the CAN circuits. The instrument cluster monitors the VSS input from the PCM and commands the speedometer with a corresponding movement of the pointer.