Code 24, VSS Transmission Output Signal - A/T - All Models: Notes

1995 GMC Forward Control 4.3 Z, StandardSECTION Notes

Vehicle Speed Sensor (VSS) output sensor is a magnetic induction type. Gear teeth pressed on outside diameter of output carrier assembly induce an alternating current in sensor when drive wheels are turning. Since vehicle speed is taken from transfer case on 4WD vehicles, output speed sensor signal on these units goes directly to control module. Code 24 will set if gear selector is not in Park or Neutral, engine speed is at least 3000 RPM and output speed is less than 250 RPM for at least 1.5 seconds.

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. Test verifies voltage at buffer module.
  2. Test checks VSS buffer ground circuit.
  3. Test checks VSS circuit at buffer module.
  4. Test verifies VSS signal at from module.
RENDER: 1.0x

NO RELATED

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