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Code 24, Vehicle Speed Sensor (VSS) 3.8L: Notes

Speed sensor, which is a Permanent Magnet (PM) generator, provides control module with vehicle speed information. PM generator, mounted in transmission, produces a pulsing AC voltage signal whenever vehicle speed is greater than 3 MPH. Voltage level and pulses increase with vehicle speed. Control module converts pulsing voltage to MPH, which is used by control module to calculate vehicle adjustments.

NOTE: Test numbers refer to numbers on diagnostic chart.
  1. If Code 36 is stored along with Code 24, go to that chart first. PM generator only produces a voltage signal if drive wheels are turning greater than 3 MPH.
  2. Before replacing control module, MEM-CAL should be checked for correct application.