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Cruise Control Is Inoperative

NOTE: To avoid misdiagnosis, perform system test and trouble shooting. See SYSTEM TEST  and TROUBLE SHOOTING. Check for stored DTCs. See appropriate TESTS W/CODES article in ENGINE PERFORMANCE section.
NOTE: The PCM will inhibit cruise control when vehicle speed is less than 25 MPH (40 km/h), when Park, Reverse, Neutral or 1st gear is indicated by the park/neutral position switch, when an over/undercharged battery condition exists, with low engine RPM, or with high engine RPM (fuel cut-off).
  1. After checking cruise control system operation, go to next step.
  2. Connect a scan tool. Turn ignition on. Inspect for VCM DTCs. Are there any DTCs found? If yes, diagnose affected DTC(s). If no, go to next step.
  3. Turn ignition off. Disconnect cruise control module connector. Connect Cruise Control Tester (J-42958). Turn ignition on. Place cruise switch in OFF position. Are the BRAKE and IGNITION lights illuminated on the cruise control tester? If yes, go to step  5. If no, go to next step.
  4. Inspect cruise fuse for an open. Is cruise fuse open? If yes, go to step  32. If no, go to step  14.
  5. Place cruise control switch in the ON position. Are the ON/OFF, BRAKE, IGNITION and CRUISE lights illuminated on the cruise control tester? If yes, go to next step. If no, go to step  16.
  6. Press and hold the SET/COAST (S/C) switch on the cruise control switch. Does the SET/COAST light illuminate on the cruise control tester? If yes, go to next step. If no, go to step  19.
  7. Press and hold the RES/ACC (R/A) switch on the cruise control switch. Does the RES/ACC light illuminate on the cruise control tester? If yes, go to next step. If no, go to step  21.
  8. Press and hold the brake pedal. Do the BRAKE light turns on and off on the cruise control tester? If yes, go to next step. If no, go to step  23.
  9. Turn ignition off. Disconnect the cruise control tester. Leave the cruise control module connector disconnected. Using a DVOM, set DVOM to AC volts and on the Hertz scale. Connect the cruise control module harness connector terminals "E" and "K". Turn ignition on. Raise and support vehicle. Inspect vehicle speed on scan tool and observe DVOM while rotating one of the drive wheels. Is the frequency within 1.11 Hz/MPH? If yes, go to next step. If no, perform Powertrain On-Board Diagnostic (OBD) System Check. Refer to appropriate SELF-DIAGNOSTICS article.
  10. Turn ignition off. Reconnect the cruise control tester. Turn ignition on. Press the INHIBIT OVERRIDE button on the tester. Press the S/C button on the tester. Does the CRUISE ENGAGE light illuminate on the tester and throttle strap extend from the cruise control module with each push of the S/C button? If yes, go to next step. If no, go to step  46.
  11. Press BRAKE button on cruise control tester. Does the CRUISE ENGAGE light turn off on the tester and the throttle strap extend fully from the cruise control module? If yes, go to next step. If no, go to step  46.
  12. Press the R/A button on the cruise control tester momentarily. Does the CRUISE ENGAGE light illuminate on the tester and the throttle strap retract into the cruise control module with each push of the R/A button? If yes, go to next step. If no, go to step  46.
  13. Press the SPD UP button on the cruise control tester momentarily. Does the CRUISE ENGAGE light remain illuminated on the tester and the throttle strap extend fully from the cruise control module and then retract to the previous position? If yes, adjust cruise control cable. If no, go to step  46.
  14. Disconnect the cruise control tester. Using a test light, connect test light between the cruise control module connector terminal "F" and ground. Does the test light illuminate? If yes, go to next step. If no, go to step  33.
  15. Using a test light, connect test light between the cruise control module connector terminals "E" and "F". Does the test light illuminate? If yes, go to step  46. If no, go to step  32.
  16. Disconnect cruise control tester. Using a test light, connect test light between the cruise control module connector terminal "A" and ground. Does the test light illuminate? If yes, go to step  46. If no, go to next step.
  17. Disconnect cruise control tester. Using a test light, connect test light between the cruise control switch connector cruise on/off signal circuit terminal and ground. Does the test light illuminate? If yes, go to step  35. If no, go to next step.
  18. Using a test light, connect test light between the cruise control switch connector ignition voltage circuit terminal and ground. Does the test light illuminate? If yes, go to step  48. If no, go to step  36.
  19. Disconnect the cruise control tester. Using a test light, connect test light between the cruise control module connector terminal "B" and ground. Press and hold the Set/Coast (S/C) switch. Does the test light illuminate? If yes, go to step  46. If no, go to next step.
  20. Using a test light, connect test light between cruise control switch connector set/coast signal circuit terminal and ground. Press and hold the Set/Coast (S/C) switch. Does the test light illuminate? If yes, go to step  37. If no, go to step  48.
  21. Disconnect the cruise control tester. Using a test light, connect test light between the cruise control module connector terminal "C" and ground. Press and hold the RES/ACC (R/A) switch. Does the test light illuminate? If yes, go to step  46. If no, go to next step.
  22. Using a test light, connect test light between the cruise control switch connector RES/ACC signal circuit terminal and ground. Press and hold the RES/ACC (R/A) switch. Does the test light illuminate? If yes, go to step  38. If no, go to step  48.
  23. Disconnect the cruise control tester. Using a test light, connect test light between the cruise control module connector terminal "G" and ground. Press and hold the brake pedal. Does the test light illuminate? If yes, go to step  26. If no, go to next step.
  24. Using a test light, connect test light between the stoplight switch connector output circuit terminal and ground. Press and hold brake pedal. Does the test light illuminate? If yes, go to step  39. If no, go to next step.
  25. Using a test light, connect test light between the stoplight switch connector ignition voltage circuit terminal and ground. Does the test light illuminate? If yes, go to step  49. If no, go to step  40.
  26. Release brake pedal. Using a test light, connect test light between the cruise control module connector terminal "D" and ground. Does the test light illuminate? If yes, go to step  46. If no, go to next step.
  27. Using a test light, connect test light between the brake pedal cruise control release switch connector output circuit terminal and ground. Does the test light illuminate? If yes, go to step  29. If no, go to next step.
  28. Using a test light, connect test light between the brake pedal cruise control release switch connector ignition voltage circuit terminal and ground. Does the test light illuminate? If yes, go to step  50. If no, go to step  41.
  29. Is vehicle equipped with a manual transmission? If yes, go to next step. If no, go to step  42.
  30. Using a test light, connect test light between the clutch pedal cruise control release switch connector input circuit terminal and ground. Does the test light illuminate? If yes, go to next step. If no, go to step  43.
  31. Using a test light connect between the clutch pedal cruise control release switch connector output circuit terminal and ground. Does the test light illuminate? If yes, go to step  42. If no, go to step  51.
  32. Repair short to ground in ignition voltage circuit to cruise control module terminal "F" and replace the cruise fuse. After repairs, recheck cruise control system for proper operation.
  33. Repair open in the ignition voltage circuit to the cruise control module. After repairs, recheck cruise control system for proper operation.
  34. Repair open in the ground circuit to the cruise control module terminal "E". After repairs, recheck cruise control system for proper operation.
  35. Repair open in the cruise on/off signal circuit to the cruise control module terminal "A". After repairs, recheck cruise control system for proper operation.
  36. Repair open in the ignition voltage circuit to the cruise control switch. After repairs, recheck cruise control system for proper operation.
  37. Repair open in the set/coast signal circuit to the cruise control module terminal "B". After repairs, recheck cruise control system for proper operation.
  38. Repair open in the RES/ACC signal circuit to the cruise control module terminal "C". After repairs, recheck cruise control system for proper operation.
  39. Repair open in the stoplight switch signal circuit to the cruise control module terminal "G". After repairs, recheck cruise control system for proper operation.
  40. Repair open in the ignition voltage circuit to the stoplight switch. After repairs, recheck cruise control system for proper operation.
  41. Repair open in the ignition voltage circuit to the brake pedal cruise control release switch. After repairs, recheck cruise control system for proper operation.
  42. Repair open in the cruise release switch signal circuit to the cruise control module terminal "D". After repairs, recheck cruise control system for proper operation.
  43. Repair open in the cruise release switch signal circuit between the brake pedal and clutch pedal cruise release switches. After repairs, recheck cruise control system for proper operation.
  44. Repair open in the cruise inhibit/enable signal circuit to the cruise control module terminal "H". After repairs, recheck cruise control system for proper operation.
  45. Repair short to voltage in the cruise inhibit/enable signal circuit to the cruise control module terminal "H". After repairs, recheck cruise control system for proper operation.
  46. Inspect cruise control module connector for poor terminal connections/terminal tension. Did you find and correct the condition? If yes, repair as necessary. After repairs, recheck cruise control system for proper operation. If no, go to step  51.
  47. Replace cruise control module. After replacing module, recheck cruise control system for proper operation.
  48. Replace cruise control switch. After replacing switch, recheck cruise control system for proper operation.
  49. Replace stoplight switch. After replacing switch, recheck cruise control system for proper operation.
  50. Replace brake pedal cruise control release switch. After replacing switch, recheck cruise control system for proper operation.
  51. Replace clutch pedal cruise control release switch. After replacing switch, recheck cruise control system for proper operation.
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