With Manual Transmission

Steps 1-7:

Steps 8-14:

DTC P0502

Circuit Description
Vehicle speed information is provided to the Powertrain Control Module (PCM) by the Vehicle Speed Sensor (VSS). The VSS is a permanent magnet generator that is mounted on the transaxle and produces a pulsing voltage when vehicle speed is over 5 km/h (3 mph). The AC voltage amplitude and frequency increases with vehicle speed. The PCM converts the pulsing voltage into km/h (mph). The PCM supplies the necessary signal to the instrument panel for speedometer, odometer operation and to the cruise control and multi-function alarm module.
DTC P0502 is a type B DTC.

Conditions for Running the DTC
^ The engine speed is 1,900 - 3,800 RPM.
^ The throttle position is less than 1 percent.
^ The engine vacuum is 70 - 80 kPa (10 - 12 psi).

Conditions for Setting the DTC
The vehicle speed is less than 3 km/h (2 mph) for 5 seconds or more.

Action Taken When the DTC Sets
^ The PCM illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive drive trip that the diagnostic runs and fails.
^ The PCM disables Cruise Control, if equipped.
^ The PCM commands the coolant fan ON.
^ The PCM records the operating conditions at the time when the Conditions for Setting the DTC are met. The PCM stores this information as Freeze Frame and Failure Records.
^ The PCM stores P0502 in PCM history.

Conditions for Clearing the MIL/DTC
^ The PCM turns OFF the MIL during the third consecutive trip in which the diagnostic runs and passes.
^ The PCM cancels the DTC default actions widen the fault no longer exists and the DTC passes.
^ The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up fancies without an emission related diagnostic fault occurring
^ A scan tool can clear the MIL/DTC.

Diagnostic Aids
Ensure the VSS is correctly torqued to the transmission housing.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
4. The vehicle speed detector in the PCM and the VSS are matched so that an open or a short to ground in the VSS low signal circuit will not usually cause a loss of speed signal or a DTC P0502 to set.
7. This step isolates the short between the VSS and the wiring.
9. The DMM will detect AC voltage if the VSS high signal circuit is shorted to ground