Section 30 (Instrument Panel - Analog): Operation: Speedometer/Odometer
WARNING: This page does not describe the selected car, but rather 11 other vehicles, including the 1999 GMC Yukon, 1999 GMC Suburban, 1999 GMC Pickup, 1999 GMC Cab & Chassis, and 1999 GMC C3500 HD. However, it is still accessible from the selected car via links, so may be relevant.
Electric speedometer and stepper motor odometer receive signals from VSS calibrator module which is generated by the Vehicle Speed Sensor (VSS). Integrated circuits control speedometer and odometer.