| CAUTION | If ECM replacement is instructed in following testing, always ensure ECM harness connector and ground circuit are okay. If either are suspect, repair and repeat testing to confirm ECM malfunction. |
Circuit Description
VSS outputs a 4-pulse signal for every revolution of the rotor shaft, which is driven by transaxle output shaft. Signal is used by ECM to determine vehicle speed. DTC is set if there is no VSS signal to ECM while vehicle is being driven or if park/neutral position switch is off. Possible causes are
- Vehicle speed sensor.
- Open or short circuit in VSS circuit.
- Instrument cluster.
- ECM.