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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.
  1. Disconnect cruise control module assembly connector. Turn ignition switch to RUN position. Using a DVOM, measure voltage between cruise control module assembly connector (harness side) terminal "F" (Brown wire) and ground. See WIRING DIAGRAMS  . If battery voltage is present, go to next step. If battery voltage is not present, go to step 3).
  2. Turn cruise control switch to ON position. Using a DVOM, measure voltage between cruise control module assembly connector (harness side) terminal "A" (Gray wire) and ground. See WIRING DIAGRAMS  . If battery voltage is present, go to step 4). If battery voltage is not present, go to step 5).
  3. Using a DVOM connected to ground, backprobe underhood wiring harness junction block connector C2 (Black) terminal A1 (Brown wire) located in left side of engine compartment. See WIRING DIAGRAMS  . If battery voltage is present, go to step 6). If battery voltage is not present, go to step 7).
  4. Hold cruise control switch in SET/COAST position. Using a DVOM, measure voltage between cruise control module assembly connector (harness side) terminal "B" (Dark Blue wire) and ground. See WIRING DIAGRAMS  . If battery voltage is present, go to step 8). If battery voltage is not present, go to step 9).
  5. Using a DVOM connected to ground, backprobe Supplemental Inflatable Restraint (SIR) coil assembly connector C2 terminal "D" (Gray wire) located under left side of instrumental panel, near steering column. See WIRING DIAGRAMS  . If battery voltage is present, go to step 10). If battery voltage is not present, go to step 11).
  6. Repair open in Brown wire between underhood wiring harness junction block and cruise control module assembly.
  7. Using a DVOM connected to ground, backprobe underhood wiring harness junction block connector C3 (Brown) terminal D2 (Brown wire) located in left side of engine compartment. See WIRING DIAGRAMS  . If battery voltage is present, go to step 27). If battery voltage is not present, go to step 12).
  8. Using a DVOM, measure voltage between cruise control module assembly connector (harness side) terminal "D" (Purple wire) and ground. See WIRING DIAGRAMS  . If battery voltage is present, go to step 13). If battery voltage is not present, go to step 14).
  9. Hold cruise control switch in SET/COAST position. Using a DVOM connected to ground, backprobe SIR coil assembly connector C2 terminal "B" (Dark Blue wire) located under left side of instrumental panel, near steering column. See WIRING DIAGRAMS  . If battery voltage is present, go to step 15). If battery voltage is not present, go to step 16).
  10. Repair open in Gray wire between SIR coil assembly and cruise control module assembly.
  11. Using a DVOM connected to ground, backprobe SIR coil assembly connector C2 terminal "A" (Pink wire) located under left side of instrumental panel, near steering column. See WIRING DIAGRAMS  . If battery voltage is present, go to step 17). If battery voltage is not present, go to step 18).
  12. Using a DVOM connected to ground, backprobe right instrument panel wiring harness junction block connector C1 (Natural) terminal B4 (Brown wire) located under right side of instrument panel. See WIRING DIAGRAMS  . If battery voltage is present, go to step 19). If battery voltage is not present, go to step 42).
  13. Using a DVOM, measure voltage between cruise control module assembly connector (harness side) terminals "D" (Purple wire) and "E" (Black wire). See WIRING DIAGRAMS  . If battery voltage is present, go to step 20). If battery voltage is not present, go to step 21).
  14. Using a DVOM connected to ground, backprobe underhood wiring harness junction block connector C2 (Black) terminal F4 (Purple wire) located in left side of engine compartment. See WIRING DIAGRAMS  . If battery voltage is present, go to step 22). If battery voltage is not present, go to step 23).
  15. Repair open in Dark Blue wire between SIR coil assembly and cruise control module assembly.
  16. Hold cruise control switch in SET/COAST position. Using a DVOM connected to ground, backprobe SIR coil assembly connector C1 terminal "B" (Dark Blue wire) located under left side of instrumental panel, near steering column. See WIRING DIAGRAMS  . If battery voltage is present, go to step 29). If battery voltage is not present, go to step 30).
  17. Using a DVOM connected to ground, backprobe SIR coil assembly connector C1 terminal "A" (Pink wire) located under left side of instrumental panel, near steering column. See WIRING DIAGRAMS  . If battery voltage is present, go to step 24). If battery voltage is not present, go to step 29).
  18. Using a DVOM connected to ground, backprobe right instrument panel wiring harness junction block connector C1 (Natural) terminal B6 (Brown wire) located under right side of instrument panel. See WIRING DIAGRAMS  . If battery voltage is present, go to step 25). If battery voltage is not present, go to step 42).
  19. Repair open in Brown wire between right instrument panel wiring harness junction block and underhood wiring harness junction block.
  20. Using a DVOM, measure voltage between cruise control module assembly connector (harness side) terminals "G" (Light Blue wire) and "E" (Black wire). See WIRING DIAGRAMS  . If battery voltage is present, check brake switch and related circuits. Repair as necessary. If battery voltage is not present, go to step 26).
  21. Repair open in Black wire between cruise control module assembly and ground connection.
  22. Repair open in Purple wire between underhood wiring harness junction block and cruise control module assembly.
  23. Using a DVOM connected to ground, backprobe underhood wiring harness junction block connector C3 (Brown) terminal A4 (Purple wire) located in left side of engine compartment. See WIRING DIAGRAMS  . If battery voltage is present, go to step 27). If battery voltage is not present, go to step 28).
  24. Using a DVOM connected to ground, backprobe SIR coil assembly connector C1 terminal "D" (Gray wire) located under left side of instrumental panel, near steering column. See WIRING DIAGRAMS  . If battery voltage is present, go to step 29). If battery voltage is not present, go to step 30).
  25. Repair open in Pink wire between right instrument panel wiring harness junction block and SIR coil assembly.
  26. Connect scan tool to Data Link Connector (DLC). Start engine. Clear any Diagnostic Trouble Codes (DTCs). Using scan tool, command PCM to allow cruise. Using a DVOM, measure voltage between cruise control module assembly connector (harness side) terminal "H" (Dark Green wire) and battery voltage. See WIRING DIAGRAMS  . If battery voltage is present, go to step 31). If battery voltage is not present, diagnose PCM and cruise disable output circuit. See appropriate TESTS W/CODES article in ENGINE PERFORMANCE section.
  27. Replace underhood wiring harness junction block.
  28. Using a DVOM connected to ground, backprobe left instrument panel wiring harness junction block connector C2 (Gray) terminal B12 (Purple wire) located under left side of instrument panel. See WIRING DIAGRAMS  . If battery voltage is present, go to step 32). If battery voltage is not present, go to step 33).
  29. Replace SIR coil assembly. See AIR BAG RESTRAINT SYSTEM article.
  30. Replace cruise control switch. See CRUISE CONTROL FUNCTIONAL SWITCHES  .
  31. Raise and support vehicle. Turn ignition switch to RUN position. Place transaxle in Neutral and slowly rotate drive wheels. Using a DVOM, measure voltage between cruise control module assembly connector (harness side) terminal "K" (Dark Green/White wire) and ground. See WIRING DIAGRAMS  . If voltage varies, go to step 34). If voltage does not vary, diagnose vehicle speed sensor. See appropriate TESTS W/CODES article in ENGINE PERFORMANCE section.
  32. Repair open in Purple wire between left instrument panel wiring harness junction block and underhood wiring harness junction block.
  33. Using a DVOM connected to ground, backprobe left instrument panel wiring harness junction block connector C3 (Black) terminal B1 (Purple wire) located under left side of instrument panel. See WIRING DIAGRAMS  . If battery voltage is present, go to step 35). If battery voltage is not present, go to step 36).
  34. Replace cruise control module assembly. See CRUISE CONTROL MODULE ASSEMBLY  .
  35. Replace left instrument panel wiring harness junction block.
  36. Using a DVOM connected to ground, backprobe cruise control brake switch connector (harness side) terminal "B" (Purple wire). See WIRING DIAGRAMS  . If battery voltage is present, go to next step. If battery voltage is not present, go to step 38).
  37. Repair open in Purple wire between left instrument panel wiring harness junction block and cruise control brake switch.
  38. Using a DVOM connected to ground, backprobe cruise control brake switch connector (harness side) terminal "A" (Brown wire). See WIRING DIAGRAMS  . If battery voltage is present, go to next step. If battery voltage is not present, go to step 40).
  39. Check cruise control brake switch for proper adjustment. See CRUISE CONTROL RELEASE SWITCH & BRAKE SWITCH ADJUSTMENT  . If cruise control brake switch is properly adjusted, replace cruise control brake switch. See CRUISE CONTROL RELEASE SWITCH & BRAKE SWITCH  .
  40. Using a DVOM connected to ground, backprobe right instrument panel wiring harness junction block connector C3 (Black) terminal A9 (Brown wire) located under right side of instrument panel. See WIRING DIAGRAMS  . If battery voltage is present, go to next step. If battery voltage is not present, go to step 42).
  41. Repair open in Brown wire between right instrument panel wiring harness junction block and cruise control brake switch.
  42. Replace right instrument panel wiring harness junction block.
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