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Speedometer/Odometer Inaccurate (Van)

  1. Ensure Vehicle Speed Sensor (VSS) Buffer are correctly calibrated for axle ratio and tire size. If problem is still present, go to next step.
  2. Connect scan tool and monitor vehicle speed. Perform a test drive of at least 5 miles at 50-65 MPH. Compare scan tool speed to speedometer speed. Record initial and final odometer reading and actual distance driven. If scan tool and speedometer indications are within 4 MPH of each other, speedometer accuracy is within specification. Go to next step. If scan tool and speedometer indications are not within 4 MPH of each other, replace instrument cluster.
  3. Drive an actual distance according to scan tool as opposed to distance indicated by odometer. If indicated ratio is .96-1.04, odometer accuracy is within specification. If indicated ratio is not .96-1.04, replace instrument cluster.
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