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Speed Sensor & Buffer GMC Sonoma Syclone

Cruise Control Systems ~458 words
  1. Ensure IGN fuse is okay. If speedometer does not operate or operates inaccurately, go to step 4). If speedometer operates accurately, turn ignition switch to RUN position. Turn cruise control switch to ON position. Check voltage at Red wire terminal of speed sensor buffer.
  2. If voltage is not present, go to next step. If about 5 volts is present, check for poor connection at Red wire terminal of speed sensor buffer. Repair as necessary. If connection is okay, replace speed sensor buffer.
  3. Check for open or poor connection in Red wire circuit between speed sensor buffer and cruise control module. If circuit is okay, replace cruise control module.
  4. Check for ECM Code 24. If ECM Code 24 is set, go to step 9). If ECM Code 24 is not set, raise and support vehicle. Disconnect speed sensor connector. Connect Signal Generator IP Tester (J-33431-B) to speed sensor connector. Set tester to 54 MPH.
  5. Turn ignition switch to RUN position. If speedometer does not display 6 MPH, go to next step. If speedometer displays 6 MPH, check for poor connection at speed sensor. If connection is okay, replace speed sensor.
  6. Turn ignition off. Disconnect tester. Disconnect speed sensor buffer 2-wire connector. Connect tester to Dark Green wire terminal of speed sensor buffer connector. Set tester to 54 MPH. Turn ignition switch to RUN position.
  7. If speedometer does not display 54 MPH, go to next step. If speedometer displays 54 MPH, check for poor connection at speed sensor buffer. If connection is okay, replace speed sensor buffer.
  8. Check for open, poor connection, short to ground or short to voltage in Dark Green wire circuit between speed sensor buffer and instrument cluster. If circuit is okay, replace speedometer.
  9. If ECM Code 24 is set as in step 4), turn ignition switch to RUN position. Check voltage at Pink/White wire terminal of speed sensor buffer connector. If voltage is not present, repair open in Pink/White wire.
  10. If battery voltage is present, check voltage between Pink/White and Black wire terminals of speed sensor buffer connector. If voltage is not present, check for open in Black wire. If battery voltage is present, turn ignition switch to RUN position.
  11. Shift transaxle into Neutral. Raise and support vehicle with drive wheels off of ground. While turning drive wheels by hand, check AC voltage between Yellow and Purple wire terminals of speed sensor buffer connector.
  12. If voltmeter indicates zero volts constantly, go to next step. If voltage fluctuates from zero to one volt, check for poor connection at speed sensor buffer connector. If connector is okay, replace speed sensor buffer.
  13. Check for open in Yellow or Purple wire between speed sensor and speed sensor buffer. If wires are okay, replace speed sensor buffer.

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