The Vehicle Speed Sensor (VSS) is a Hall Effect sensor mounted above the transaxle differential. The sensor is triggered by the ring gear teeth passing below it. The VSS pulse signal to the speedometer/odometer is monitored by the PCM speed control circuitry to determine vehicle speed and to maintain speed control set speed.
Removal & Installation
- Disconnect the negative battery cable.
- Remove the air intake assembly.
Disconnect the Vehicle Speed Sensor (VSS) electrical connector.
NOTEClean the area around the VSS before removal to prevent dirt from the entering the transaxle.
- Remove the VSS retaining bolt and remove the VSS.
- Install the VSS using a new O-ring. Tighten the retaining bolt to 60 inch lbs. (7 Nm).
- Connect the VSS electrical connector.
- Install the air intake assembly.
- Connect the negative battery cable.
- Using a diagnostic scan tool, check for the presence of any Diagnostic Trouble Codes (DTCs). Record and address these codes as necessary.
- If no codes are present, review the scan tool environmental data. If possible, try to duplicate the conditions under which the DTC set.
- If applicable, actuate the component with the scan tool.
- Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
- Look for the data to change, the actuation to be interrupted, or for the DTC to reset during the wiggle test.
- Refer to any Technical Service Bulletins (TSBs) that may apply.
- Turn the ignition off.
- Visually inspect the related wire harness. Disconnect all the related harness connectors. Look for any chafed, pierced, pinched, partially broken wires and broken, bent, pushed out, or corroded terminals.
- Perform a voltage drop test on the related circuits between the suspected component and the Powertrain Control Module (PCM).
- Inspect and clean all PCM, engine, and chassis grounds that are related to the most current DTC.
- If numerous trouble codes were set, use a schematic and inspect any common ground or supply circuits.
- For intermittent Misfire DTCs check for restrictions in the Intake and Exhaust system, proper installation of Sensors, vacuum leaks, and binding components that are run by the accessory drive belt.
- Use the scan tool to perform a System Test if one applies to the component.
- A co-pilot, data recorder, and/or lab scope should be used to help diagnose intermittent conditions.