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Test C: Cruise Control Inoperative/Malfunctioning: Notes

  1. Turn ignition off. Disconnect PCM 64-pin Black connector (C2). Turn ignition on with engine off. Using a test light, probe RESUME/DECEL (Black/Brown wire) and SET/ACCEL (Black/Yellow wire) signal circuits between PCM connector C2 and ground. See WIRING DIAGRAMS  . Observe test light. If test light is on, go to step  10 . If test light is off, go to next step.
  2. Using a test light, probe ON signal circuit (Black/Red wire) between PCM harness connector (C2) and ground. Observe test light. If test light is on, go to step  4 . If test light is off, go to next step.
  3. Turn ignition off. Disconnect cruise control switch at multifunction turn signal lever connector. Turn ignition on with engine off. Using a test light, probe cruise control switch ignition positive circuit (Brown wire) between cruise control switch connector and ground. See WIRING DIAGRAMS  . Observe test light. If test light is on, go to step  11 . If test light is off, go to step  12 .
  4. Using a test light, probe SET/ACCEL signal circuit (Black/Yellow wire) between PCM connector C2 and ground. See WIRING DIAGRAMS  . Press and hold SET/ACCEL switch. Observe test light. If test light is on, go to next step. If test light is off, go to step  13 .
  5. Using a test light, probe RESUME/DECEL signal circuit (Black/Brown wire) between PCM connector C2 and ground. See WIRING DIAGRAMS  . Press and hold RESUME/DECEL switch. Observe test light. If test light is on, go to next step. If test light is off, go to step  14 .
  6. Using a test light, probe brakelight signal circuit (Black/Yellow wire) between PCM connector C2 and ground. See WIRING DIAGRAMS  . Observe test light. If test light is on, go to step  20 . If test light is off, go to next step.
  7. With test light still connected from previous step, press brake pedal. Observe test light. If test light is on, go to next step. If test light is off, go to step  15 .
  8. Using a test light, probe cruise release signal circuit (Black/Brown wire) between PCM connector C2 and ground. See WIRING DIAGRAMS  . Observe test light. If test light is on, go to next step. If test light is off, go to step  16 .
  9. With test light still connected from previous step, press brake pedal. Observe test light. If test light is on, go to step  18 . If test light is off, go to step  24 .
  10. Check RESUME/DECEL (Black/Brown wire) or SET/ACCEL (Black/Yellow wire) signal circuit (whichever circuit caused test light to turn on from step 2)  for a short to voltage. See WIRING DIAGRAMS  . If a circuit condition was identified and corrected, go to step  29 . If a circuit condition was not identified and corrected, go to step  22 .
  11. Check ON signal circuit (Black/Red wire) for a short to voltage. See WIRING DIAGRAMS  . If a circuit condition was identified and corrected, go to step  29 . If a circuit condition was not identified and corrected, go to step  23 .
  12. Check the ignition positive voltage circuit (Brown wire) of cruise control switch for an open circuit, high resistance or short to ground. Also check cruise control signal circuits for a short to ground. See WIRING DIAGRAMS  . Repair as necessary. If a circuit condition was identified and corrected, go to step  29 . If a circuit condition was not identified and corrected, go to step  23 .
  13. Check SET/ACCEL signal circuit (Black/Red wire) for a open circuit or short to ground. See WIRING DIAGRAMS  . If a circuit condition was identified and corrected, go to step  29 . If a circuit condition was not identified and corrected, go to step  23 .
  14. Check RESUME/DECEL signal circuit (Black/Brown wire) for a open circuit, high resistance or short to ground. See WIRING DIAGRAMS  . If a circuit condition was identified and corrected, go to step  29 . If a circuit condition was not identified and corrected, go to step  23 .
  15. Check ignition positive voltage circuit for brakelight circuit (Red wire) for a open circuit, high resistance or short to ground. See WIRING DIAGRAMS  . If a circuit condition was identified and corrected, go to step  29 . If a circuit condition was not identified and corrected, go to step  19 .
  16. Check cruise release signal circuit (Brown/White wire) for a open circuit, high resistance or short to ground. See WIRING DIAGRAMS  . If a circuit condition was identified and corrected, go to step  29 . If a circuit condition was not identified and corrected, go to step  17 .
  17. Check ignition positive voltage circuit of cruise release switch (Brown wire) for a open circuit, high resistance or short to ground. See WIRING DIAGRAMS  . If a circuit condition was identified and corrected, go to step  29 . If a circuit condition was not identified and corrected, go to step  21 .
  18. Check cruise release signal circuit (Brown/White wire) for a short to voltage. See WIRING DIAGRAMS  . If a circuit condition was identified and corrected, go to step  29 . If a circuit condition was not identified and corrected, go to step  21 .
  19. Check brakelight signal circuit (Black/Yellow wire) for a open circuit, high resistance or short to ground. See WIRING DIAGRAMS  . If a circuit condition was identified and corrected, go to step  29 . If a circuit condition was not identified and corrected, go to step  22 .
  20. Check brakelight signal circuit (Black/Yellow wire) for a short to voltage. See WIRING DIAGRAMS  . If a circuit condition was identified and corrected, go to step  29 . If a circuit condition was not identified and corrected, go to step  22 .
  21. Inspect cruise control release switch connector for poor connections. Repair as necessary. If a condition was identified and corrected, go to step  29 . If a condition was not identified and corrected, go to step  25 .
  22. Inspect brakelight switch connector for poor connections. Repair as necessary. If a condition was identified and corrected, go to step  29 . If a condition was not identified and corrected, go to step  26 .
  23. Inspect cruise control switch at multifunction turn signal lever connector for poor connections. Repair as necessary. If a condition was identified and corrected, go to step  29 . If a condition was not identified and corrected, go to step  27 .
  24. Inspect PCM connectors for poor connections. Repair as necessary. If a condition was identified and corrected, go to step  29 . If a condition was not identified and corrected, go to step  28 .
  25. Replace cruise control release switch. See CRUISE CONTROL RELEASE SWITCH  under REMOVAL & INSTALLATION. After replacing cruise control release switch, go to step  29 .
  26. Replace brakelight switch. See BRAKELIGHT SWITCH  under REMOVAL & INSTALLATION. After replacing brakelight switch, go to step  29 .
  27. Replace multifunction turn signal lever. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT. After replacing multifunction turn signal lever, go to step  29 .
  28. Replace PCM. See POWERTRAIN CONTROL MODULE  under REMOVAL & INSTALLATION. After replacing PCM, go to next step.
  29. Using scan tool, clear DTC. Drive vehicle within parameters which allow cruise control operation. Operate cruise control system. If cruise control system functions properly, repair is complete. If cruise control system does not function properly, see DIAGNOSTIC AIDS  .
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