Speedometer/Odometer

The Speedometer and 0dometer's Solid State Logic is powered from GAUGES Fuse 4 through the PNK (39) wire to the Instrument Cluster. It receives a square wave 4000 PPM (pulses per mile) pulse from the Vehicle Control Module (VCM, Gasoline Engines) or Vehicle Speed Sensor Buffer (VSSB, Diesel Engines) through the DK GRN (389) wire. The solid state electronics positions the Speedometer pointer in response to the pulse rate. The electronics also drives the odometer indication in response to the pulse rate over time.

The speedometer's rated accuracy at 65 mph is plus or minus 2 mph (63 to 67 mph). At 20 mph, the rated accuracy is plus or minus 4 mph (16 to 24 mph). Variations in voltage and inaccuracies in the other circuit components may increase the error.