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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. Connect a test light between cruise control module assembly connector (harness side) terminal "F" (Brown wire) and ground. See WIRING DIAGRAMS . If test light illuminates, go to next step. If test light does not illuminate, repair open in Brown wire between instrument panel fuse block and cruise control module assembly.
  2. Connect a test light between cruise control module assembly connector (harness side) terminal "D" (Purple wire) and ground. See WIRING DIAGRAMS . If test light illuminates, go to next step. If test light does not illuminate, check TCC/brake switch for proper adjustment. See TCC/BRAKE SWITCH (MOTORHOME) ADJUSTMENT . If TCC/brake switch is properly adjusted, check for open in Purple wire between TCC/brake switch and cruise control module assembly. If Purple wire is okay, replace TCC/brake switch. See BRAKE & CLUTCH RELEASE SWITCHES .
  3. Connect a test light between cruise control module assembly connector (harness side) terminal "G" (Light Blue wire) and ground. See WIRING DIAGRAMS . If test light does not illuminate, go to next step. If test light illuminates, check brake switch for proper adjustment. See TCC/BRAKE SWITCH (MOTORHOME) ADJUSTMENT . If brake switch is properly adjusted, repair open in Light Blue wire between brake switch and cruise control module assembly.
  4. Turn cruise control switch to ON position. Connect a test light between cruise control module assembly connector (harness side) terminal "A" (Gray wire) and ground. See WIRING DIAGRAMS . If test light does not illuminate, go to next step. If test light illuminates, go to step 7).
  5. Using a test light connected to ground, backprobe multifunction lever (cruise control switch) terminal "B" (Gray wire). See WIRING DIAGRAMS . If test light does not illuminate, go to next step. If test light illuminates, repair open in Gray wire between multifunction lever (cruise control switch) and cruise control module assembly.
  6. Using a test light connected to ground, backprobe multifunction lever (cruise control switch) terminal "A" (Brown wire). See WIRING DIAGRAMS . If test light does not illuminate, repair open in Brown wire between multifunction lever (cruise control switch) and instrumental panel fuse block. If test light illuminates, replace multifunction lever (cruise control switch). See STEERING COLUMN SWITCHES article.
  7. Connect a test light between cruise control module assembly connector (harness side) terminals "A" (Gray wire) and "E" (Black/White wire). See WIRING DIAGRAMS . If test light illuminates, go to next step. If test light does not illuminate, repair open in Black/White wire or Black wire between cruise control module assembly and ground connection.
  8. Connect a test light between cruise control module assembly connector (harness side) terminal "B" (Dark Blue wire) and ground. See WIRING DIAGRAMS . Press and hold cruise control switch in SET position. If test light does not illuminate, go to next step. If test light illuminates, go to step 10).
  9. Using a test light connected to ground, backprobe multifunction lever (cruise control switch) connector (harness side) terminal "D" (Dark Blue wire). See WIRING DIAGRAMS . Press and hold cruise control switch in SET position. If test light illuminates, repair open in Dark Blue wire between multifunction lever (cruise control switch) and cruise control module assembly. If test light does not illuminate, replace multifunction lever (cruise control switch). See STEERING COLUMN SWITCHES article.
  10. 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 is less than 7 volts, check for an open in Dark Green/White between cruise control module assembly and Vehicle Control Module (VCM). If voltage is greater than 7 volts, replace cruise control module assembly. See CRUISE CONTROL MODULE ASSEMBLY .
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