J2000/Sunbird V6-191 3.1L (1992)
Speedometer Head: Description and Operation
Base Cluster
The Speedometer pointer is moved by the magnetic fields of two coils. These coils are driven by a solid state unit.
The Vehicle Speed Sensor, located in the transaxle, generates an AC voltage that is sent to the Engine Control Module (ECM). The ECM processes
this voltage into a square wave. The pulses generated are sent to the Speedometer at 4000 pulses per mile.