For 1990-2009 cars

### Circuit Description

Vehicle speed values are provided by the vehicle speed sensor (VSS). The sensor is a permanent magnet variable reluctance sensor (VRS) mounted on the differential area of the transaxle housing. The PM generator produces a pulsing voltage whenever vehicle speed is above 5 km/h (3 mph). These pulses occur 16 times per each revolution of the differential housing and are translated to provide vehicle speed in miles per hour.

### Conditions for Setting the DTC

Important: The VSS signal is continuously checked once the following conditions are met. If the VSS signal is missing, the speedometer will be inoperative.

DTC P0500 will set if there is no VSS signal when:

• | The engine speed is between 1,400-4,000 RPM. The MAP sensor indication is less than 0.5 volts, or less than 23 kPa (3 psi), for greater than 5 seconds.

• | The vehicle is not in park/neutral for an automatic transaxle.

### Diagnostic Aids

• | The speedometer will not work if the VSS subsystem has failed.

• | If the VSS reading is accurate and the speedometer is incorrect, refer to the Audio System or Instrument Panel, Gages, and Console sections.

• | The VSS resistance is 800-1,600 ohms.

• | If the problem is intermittent, wiggle the wires while monitoring the VSS signal on the scan tool and watch for the signal to jump for a loss of signal.

• | The PCM will calculate VSS based on RPM and the TP sensor signal if DTC P0500 is set, but the speedometer will remain inoperative.