Speedometer/Odometer

The Vehicle Speed Sensor (VSS) is a gear-driven permanent magnet generator housed in the vehicle's transaxle. This sensor generates a sine wave output with a frequency proportional to vehicle speed. The Powertrain Control Module (PCM) converts this signal to an output that is switched to ground at a frequency of 4000 pulses per mile. This signal (circuit 817) drives the speedometer and odometer and is used by other components.

The season odometer displays the total accumulated miles/km of the vehicle. This value is permanently stored in the Electronically Erasable Programmable Read Only Memory (EEPROM) of the instrument cluster. If an odometer malfunction occurs or if the instrument cluster must be replaced, an authorized Delco (R) service center must be contacted to program proper vehicle specifics (including mileage) for the instrument cluster.

NOTE: When replacing an instrument cluster, the law requires the odometer reading of the replacement unit to be set to register the same mileage as the prior odometer. If the same mileage cannot be set. the law requires the replacement odometer be set to zero and a label be installed on the driver's door frame to show previous odometer reading and the date of replacement.

The trip odometer displays the accumulated mileage/km to the tenths of a mile/km since the last reset. This value is stored in Keep Alive Memory (KAM) of the instrument cluster. The trip odometer nay be reset on the base level cluster by pressing the TRIP RESET button. The trip odometer may be reset on the uplevel cluster by pressing the RESET button when the trip information is being displayed in the Driver Information Center (DIC). If a button is not used to reset the trip odometer, the display will roll over automatically as follows:
^ The trip odometer will roll over at 999.9 miles when operated in English mode and at 999.9 km in metric mode.
^ When the trip odometer is displaying more than 621.4 miles (operating in English mode) and the English/metric button is pressed, the trip odometer will reset to zero and display km values. If the English/metric button is pushed again, the cluster will convert the displayed km value into miles.