P0500
DTC P0500: VSS Circuit Malfunction1. Test-drive the vehicle.
2. Check the vehicle speed with the scan tool or the HDS.
Is the correct speed indicated?
YES - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals 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 A18 and A24.
Does the voltage pulse between 0 V and 5 V or battery voltage?
YES - Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM.
NO - Go to step 9.
9. Turn the ignition switch OFF.
10. Disconnect ECM connector A (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 A18 and A24.
Does the voltage pulse between 0 V and 5 V or battery voltage?
YES - Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM.
NO - Check for a short or an open in the wire between the ECM (A18) and the VSS. If the wire is OK, test the VSS.