Skylark V6-3100 3.1L VIN M SFI (1996)
Vehicle Speed Sensor/Transducer - Cruise Control: Description and Operation
On models with conventional instrument panels, a speedometer frame mounted optic head is used to pick up light reflected by a speedometer cable
mounted blade. The reflected light is produced by a light emitting diode (LED). As the speedometer cable mounted blade enters the LED light beam,
the light is reflected into the optic head. From there, the light enters a photocell in the optic head and produces a low power speed signal. This signal is
sent to a buffer for amplification and conditioning, then to the controller.
On models with electronic speedometers or electronic instrumentation, a transmission mounted speed sensor is used. This sensor utilizes a
permanent magnet (PM) to generate vehicle speed information to the controller. Some models use a buffer amplifier to modify the sensor output.