F 250 4WD Super Duty V10-6.8L VIN V (2005)
Speedometer Head: Description and Operation
Speedometer
The vehicle speed signal (VSS) is generated in the anti-lock brake system (ABS) and sent to the powertrain control module (PCM) through hardwired
circuitry. The PCM transmits the VSS data to the instrument cluster over the high speed controller area network (HS-CAN) communication bus. If the
instrument cluster fails to receive the VSS input from the PCM, the instrument cluster indicates 0 km/h (O mph) on the speedometer.
