Speedometer Head: Description and Operation

The speedometer cable for the electronic cluster is identical to the cable used on conventional speedometers. The cable drives a slotted encoder wheel in the odometer assembly. As the slots in the rotating encoder wheel pass by the optical sensor, the optical sensor generates an electrical pulse for each slot. The electrical pulse is used by the speedometer electronics to determine the vehicle speed. The encoder/optical sensor outputs 16,000 pulses per mile (9942 pulses per kilometer).