Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptor
DTC P0500: Vehicle Speed Sensor (VSS) CircuitDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
VSS Low Signal | -- | P0500 | -- | -- |
VSS High Signal | P0500 | P0500 | P0500 | -- |
Circuit/System Description
The 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 to the transmission and produces a pulsing voltage. The AC voltage amplitude and frequency increases with vehicle speed. The PCM converts the pulsing voltage into km/h (mph). The PCM supplies the VSS signal to the following components:
| • | The instrument panel for speedometer and odometer operation |
| • | The cruise control module |
Conditions for Running the DTC
All conditions are met for 2 seconds.
| • | DTC P0016, P0106, P0107, P0108, P0120 or P0220 are not set. |
| • | The engine coolant temperature is 35°C (95°F) or greater. |
| • | The throttle position (TP) sensor is greater than 3.5 percent. |
| • | The engine speed is greater than 1,000 RPM. |
| • | Manifold absolute pressure (MAP) is 40-100 kPa (6-15 psi) with A/C OFF. |
| • | MAP is 45-100 kPa (7-15 psi) with A/C ON. |
Conditions for Setting the DTC
The PCM detects no vehicle speed for 50 seconds.
Action Taken When the DTC Sets
P0500 is a Type B DTC.
Conditions for Clearing the DTC
P0500 is a Type B DTC.
Reference Information
Schematic Reference
Manual Transmission Schematics
Connector End View Reference
Description and Operation
Transmission System Description and Operation
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Special Tools
J 35616 GM-Approved Terminal Test Kit
Circuit/System Verification
- Monitor VSS parameter on the scan tool. The VSS parameter should increase as the drive wheel speed increases.
- Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records List.
Circuit/System Testing
- Disconnect the PCM harness connector X1.
- Measure for 1,680-3,160 ohms between the VSS high signal circuit terminal 21 and the VSS low signal circuit terminal 20.
- Measure for more than 10 ohms of resistance between the VSS high signal circuit terminal 21 and ground.
- Measure for more than 10 ohms of resistance between the VSS low signal circuit terminal 20 and ground.
- Reconnect the PCM connector. Disconnect the VSS connector.
- Ignition ON, test the VSS high signal circuit terminal 1 for a short to voltage.
| ⇒ | If the value is greater than 3,160 ohms test the VSS high signal circuit and the VSS low signal circuit for an open/high resistance. If the circuits/connections test normal, replace the vehicle speed sensor. |
| ⇒ | If the value is less than 1,680 ohms test the VSS high signal and the VSS low signal circuits for a shorted together condition. If the circuits/connections test normal, replace the vehicle speed sensor. |
| ⇒ | If the value is less than the specified range, repair the short to ground. |
| ⇒ | If the value is less than the specified range, repair the short to ground. |
| ⇒ | If all circuits/connections test normal, test or replace the VSS. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
| • | Control Module References for PCM replacement, setup and programming |
