P0500
DTC P0500: VSS Circuit Malfunction1. Test-drive the vehicle.
2. Check the vehicle speed sensor reading with the scan tool.
Is the correct speed indicated?
YES - Intermittent failure, system is OK at this time. Check for poor connections or loose wires at the VSS and at the ECM.
NO - Go to step 3.
3. Turn the ignition switch OFF.
4. Block the rear wheels and set the parking brake.
5. Raise the front of the vehicle, and make sure it is securely supported.
6. Turn the ignition switch ON (II).
7. Block the right front wheel, and slowly rotate the left front wheel.
8. Measure voltage between ECM connector terminals B20 and C23.
Does the voltage pulse between 0 V and 5V ?
YES - Substitute a known-good ECM and recheck. If the symptom/indication goes away, replace the original ECM.
NO - Go to step 9.
9. Turn the ignition switch OFF.
10. Disconnect ECM connector C (31P).
11. Turn the ignition switch ON (II).
12. Block the right front wheel, and slowly rotate the left front wheel.
13. Measure voltage between ECM connector terminals B20 and C23.
Does the voltage pulse between 0 V and 5V ?
YES - Substitute a known-good ECM and recheck. If the symptom/indication goes away, replace the original ECM.
NO - Check these items:
- A short or an open in the wire between the ECM (C23) and the VSS.
- If the wire is OK, test the VSS.