Bonneville V6-3800 3.8L VIN L SFI (1995)
Vehicle Speed Sensor: Component Tests and General Diagnostics
Circuit Operation
The vehicle speed sensor generates a signal that is proportional to vehicle speed. The signal produced is a sine wave, which the Powertrain Control
Module (PCM) processes into a square wave to supply inputs to the speedometer, the multi-function chime (MFC) module, computer command ride
(CCR) module (if equipped), and heads-up display module (if equipped).
The PCM takes the voltage pulses from the vehicle speed sensor, through the PPL and YEL wires, and uses them to close a solid-state output switch. The
output terminal is switched to ground at a rate that is proportional to vehicle speed.
System Diagnosis
Refer to Symptom Table for appropriate diagnostic procedure.
