Speedometer/Odometer

GAUGES fuse 4 powers the speedometer and the odometer solid state logic through CKT 39 (PNK) to the instrument cluster. The speedometer and the odometer solid state logic receives a square wave 4000 pulse per mile (PPM) from the Vehicle Control Module (VCM) in gasoline vehicles, or from the Vehicle Speed Sensor (VSS) buffer in diesel vehicles through CKT 389 (DK GRN). The solid state electronics position the speedometer pointer in response to the pulse rate. The electronics also drive the odometer indication in response the pulse rate over time. The speedometer's rated accuracy at 104.6 km/h (65 mph) is within 3.2 km/h (2 mph) or 101.4 - 107.8 km/h (63-67 mph). At 32.2 km/h (20 mph), the rated accuracy is within 6.4 km/h (4 mph) or 25.7-38.6 km/h (16-24 mph). Variations in voltage and inaccuracies in the other circuit components may increase the error.