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Cruise Control Inoperative

NOTE: To avoid misdiagnosis, ensure preliminary inspection and all checks have been performed. See TROUBLE SHOOTING  .
  1. Turn cruise control switch to OFF position. Disconnect cruise control module harness connector. Turn ignition on. Measure voltage between cruise control module harness connector (harness side) terminal "F" (Pink wire) and ground. Voltage should be 10-15 volts. If voltage is not as specified, go to next step. If voltage is as specified, go to step  3 .
  2. Repair open in Pink wire between cruise control module and engine compartment fuse/relay center. After repairs, go to step  30 .
  3. Measure voltage between cruise control module harness connector (harness side) terminals "F" (Pink wire) and "E" (Black/White wire). Voltage should be 10-15 volts. If voltage is not as specified, go to next step. If voltage is as specified, go to step  5 .
  4. Repair open in Black/White wire between cruise control module and ground. After repairs, go to step  30 .
  5. Measure voltage between ground and 48-pin harness connector C202, terminal E1 (Pink wire) located at base of steering column. Voltage should be 10-15 volts. If voltage is not as specified, go to next step. If voltage is as specified, go to step  7 .
  6. Repair open in Pink wire between rear compartment fuse block and ABS/TCC switch. After repairs, go to step  30 .
  7. Turn cruise control switch to ON position. Measure voltage between ground and 48-pin harness connector C202, terminal E2 (Gray wire) located at base of steering column. Voltage should be 10-15 volts. If voltage is not as specified, go to next step. If voltage is as specified, go to step  9 .
  8. Check for poor cruise control switch connections. Clean or repair as necessary. If no problem is found, replace multifunction lever. See appropriate STEERING COLUMN SWITCHES article. After repairs, go to step  30 .
  9. Measure voltage between cruise control module harness connector terminal "A" (Gray wire) and ground. Voltage should be 10-15 volts. If voltage is not as specified, go to next step. If voltage is as specified, go to step  11 .
  10. Repair open or short to ground in Gray wire between cruise control module and multifunction lever. After repairs, go to step  30 .
  11. Measure voltage between ground and 48-pin harness connector C202, terminal E3 (Dark Blue wire) located at base of steering column. Voltage should be 10-15 volts. If voltage is as specified, go to next step. If voltage is not as specified, go to step  8 .
  12. Measure voltage between cruise control module harness connector terminal "B" (Dark Blue wire) and ground. Voltage should be 10-15 volts. If voltage is not as specified, go to next step. If voltage is as specified, go to step  14 .
  13. Repair open or short to ground in Dark Blue wire between cruise control module and multifunction lever. After repairs, go to step  30 .
  14. Measure voltage between cruise control module harness connector terminal "G" (Light Blue wire) and ground. Voltage should be less than .5 volt. If voltage is not as specified, go to next step. If voltage is as specified, go to step  16 .
  15. Repair short to battery voltage in Light Blue wire. After repairs, go to step  30 .
  16. Measure voltage between cruise control module harness connector terminal "D" (Purple wire) and ground. Press brake pedal, and then release. Voltage should be less than .5 volt with pedal depressed, and 10-15 volts with pedal released. If voltage is not as specified, go to next step. If voltage is as specified, go to step  22 .
  17. Turn ignition off. Disconnect ABS/TCC switch harness connector. Turn ignition on. Measure voltage between cruise control module harness connector terminal "A" (Gray wire) and ground. Voltage should be 10-15 volts. If voltage is not as specified, go to next step. If voltage is as specified, go to step  19 .
  18. Repair open or short in Pink wire between rear compartment fuse block and ABS/TCC switch. After repairs, go to step  30 .
  19. Turn ignition off. Connect a fused jumper wire between ABS/TCC switch harness connector terminals "A" (Pink wire) and "B" (Purple wire). Turn ignition on. Measure voltage between cruise control module harness connector terminal "D" (Purple wire) and ground. Voltage should be 10-15 volts. Remove jumper wire. Voltage should be less than .5 volt. If voltage is not as specified, go to next step. If voltage is as specified, go to step  21 .
  20. Repair open or short in Purple wire between cruise control module and ABS/TCC switch. After repairs, go to step  30 .
  21. Check ABS/TCC switch harness connections. Repair as necessary. After repairs, go to step  30 .
  22. Raise and support vehicle with drive wheels off ground. Measure voltage between cruise control module harness connector terminal "K" (Dark Green wire) and ground. Rotate drive wheels. If voltage does not vary, go to next step. If voltage varies, go to step  24 .
  23. Repair open or short in Dark Green/White wire between cruise control module and PCM. After repairs, go to step  30 .
  24. Turn ignition off. Reconnect cruise control module harness connector. Disconnect PCM harness connector C1. Turn ignition on. Measure voltage between PCM harness connector C1, terminal No. 26 (Dark Green wire) and ground. If 10-15 volts does not exist, go to next step. If 10-15 volts exists, go to step  27 .
  25. Check for an open or short to ground in Dark Green wire between cruise control module and PCM. If Dark Green wire is open or shorted, go to next step. If Dark Green wire is okay, go to step  28 .
  26. Repair open or short in Dark Green wire between cruise control module and PCM. After repairs, go to step  30 .
  27. Turn ignition off. Reconnect PCM harness connector C1. Disconnect cruise control module harness connector. Turn ignition on. Using scan tool, clear DTCs. Select PCM, SPECIAL FUNCTIONS, and then ENGINE OUTPUT CONTROLS. Select CRUISE INHIBIT and command PCM to turn cruise inhibit off. Measure voltage between cruise control module harness connector terminal "H" (Dark Green wire) and ground. Voltage should be 10-15 volts with cruise inhibit off (NO) and less than .5 volt with cruise inhibit on (YES). If voltage is not as specified, go to next step. If voltage is as specified, go to step  29 .
  28. Ensure cruise control module harness connector is clean and tight. If connector is okay, replace cruise control module. See CRUISE CONTROL MODULE  under REMOVAL & INSTALLATION. After repairs, go to step  30 .
  29. Check PCM. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. Repair as necessary. After repairs, go to next step.
  30. Ensure all components are installed and connected. Recheck system. See SYSTEM CHECK  under TROUBLE SHOOTING.
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