P0500

Circuit Description
A toothed wheel mounted on the output shaft of the transmission generates an AC voltage pulse as it moves past the Vehicle Speed Sensor (VSS). The VSS contains a permanent magnet surrounded by a coil of wire, which produces a magnetic field. The toothed wheel interrupts the magnetic field that generates an AC voltage pulse. As the vehicle speed increases the AC voltage pulse rate increases. The PCM supplies the VSS signal (via the VSS output circuit) to the following components:
^ Body Control Module (BCM)
^ Instrument Panel Cluster (IPC)
^ Electronic Suspension Control Module (if equipped)

Conditions for Running the DTC
^ DTCs P0107, P0108, P0117, P0118, P0506, P0507, P1120, P1220, P1221 are not set.
^ The ECT is greater than 35°C (95°F).
^ The engine speed is greater than 1000 RPM.
^ The TP sensor angle is greater than 5%, but less than 100%.
^ The MAP is between 40 kPa and 99 kPa when the A/C is OFF.
^ The MAP is between 45 kPa and 99 kPa when the A/C is ON.
^ All conditions met for 2 seconds.

Conditions for Setting the DTC
The PCM detects vehicle speed at 0 km/h (0 mph) for 1 minute and 40 seconds.

Action Taken When the DTC Sets
^ The PCM illuminates the Malfunction Indicator Lamp on the second consecutive ignition cycle that the diagnostic runs and fails.
^ The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure records.

Conditions for Clearing the MIL/DTC
^ The PCM turns the MIL OFF after three consecutive ignition cycles that the diagnostic runs and does not fail.
^ A last test failed (current DTC) clears when the diagnostic runs and does not fail.
^ A History DTC clears after forty consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.
^ Use a scan tool in order to clear the MIL/DTC.

Diagnostic Aids

Important:
^ Remove any debris from the PCM/TAC module connector surfaces before servicing the PCM/TAC module. Inspect the PCM/TAC module connector gaskets when diagnosing/replacing the modules. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM/TAC modules.
^ For any test that requires probing the PCM or a component harness connector, use the Connector Test Adapter kit J 35616-A. Using this kit prevents damage to the harness/component terminals.
^ The following may cause an intermittent:
- Poor connections.
- Mis-routed harness.
- Rubbed through wire insulation.
- Broken wire inside the insulation.
^ Inspect all of the circuits to the PCM and the VSS. Inspect the terminal connections at the VSS harness connector and at the PCM harness connector. If all of the circuits and connections are OK, replace the PCM.
^ Using Freeze Frame and/or Failure Records data may aid in locating an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data can aid in determining how many miles since the DTC set. The Fail Counter and Pass Counter can also aid determining how many ignition cycles the diagnostic reported a pass and/or a fail. Operate the vehicle within the same freeze frame conditions (RPM, load, vehicle speed, temperature etc.) that you observed. This isolates when the DTC failed.
^ For an intermittent, refer to Symptoms. Symptom Related Diagnostic Procedures

Test Description
The numbers below refer to the step numbers on the diagnostic table.
2. This DTC is only for manual transmission vehicles.