GM Service Manual Online
For 1990-2009 cars only

Use this procedure in order to inspect the cruise control system operating modes. Always use this procedure after you complete repair work on the cruise system. Use this test on models with automatic transmission.

  1. Slide the turn signal lever to the ON position.
  2. Test the Low Speed Inhibit. Verify that the cruise control does not engage.
  3. 2.1. Drive the vehicle at 32 km/h (20 mph).
    2.2. Depress and release the SET button.
  4. Test the Set Speed. The cruise control should engage at approximately 89 km/h (55 mph).
  5. 3.1. Drive the vehicle at a steady speed of 89 km/h (55 mph).
    3.2. Depress and release the SET button.
  6. Depress the brake pedal in order to inspect the Brake Release.
  7. The cruise control must release the throttle in order to allow the vehicle speed to drop. Verify that the system does not re-engage after you release the brake.

  8. Test the Resume feature.
  9. • Momentarily (less than 1 second) slide and hold the cruise switch to the R/A position with the vehicle speed at approximately 72 km/h (45 mph).
    • Verify that the vehicle accelerates to approximately 89 km/h (55 mph).
  10. Test the Coast feature. The cruise control should hold the vehicle speed at approximately 80 km/h (50 mph).
  11. • Depress and hold the SET button.
    • Allow the vehicle speed to drop to 80 km/h (50 mph).
    • Release the button.
  12. Test the Accelerate feature. The cruise control should hold the vehicle speed at approximately 89 km/h (55 mph).
  13. 7.1. Slide the cruise switch to the R/A position. Hold the switch.
    7.2. Allow the vehicle sped to increase to 89 km/h (55 mph).
    7.3. Release the switch.
  14. Inspect the OFF switch.
  15. Turn the turn signal lever cruise switch to the OFF position. Verify that the cruise control system disengages.

If the preliminary inspections do not reveal a solution, refer to Engine Controls.