Cutlass Ciera L4-2.2L VIN 4 (1995)
Vehicle Speed Sensor: Component Tests and General Diagnostics
Circuit Operation
The Vehicle Speed Sensor is a gear-driven Permanent Magnet Generator housed in the vehicle's Transaxle. This sensor generates a sine wave output
with a frequency proportional to vehicle speed. The PCM converts this signal to an output that is switched to ground at a frequency of 4000 pulses per
mile at the CKT 389 output. This output is pulled up to 5 volts or greater by the components that use this speed signal as an input.
System Diagnosis
Refer to the Symptom Table for the appropriate diagnostic procedures. See: Symptom Related Diagnostic Procedures/- Symptom Table
Vehicle Speed Sensor Diagnosis
A Tech 1 scan tool mph display should closely match the speedometer reading with drive wheels turning. A fault in the Vehicle Speed Sensor circuit
should set a DTC 24 Vehicle Speed Sensor (VSS) Circuit. See: Powertrain Management/Computers and Control Systems/Testing and Inspection