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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. Connect test light between cruise control module harness connector (harness side) terminal "F" (Pink wire) and ground. If test light illuminates, go to next step. If test light does not illuminate, repair poor connection or open in Pink wire between cruise control module and splice S165.
  2. Connect test light between cruise control module harness connector (harness side) terminals "F" (Pink wire) and "E" (Black wire). If test light illuminates, go to next step. If test light does not illuminate, repair poor connection or open in Black wire between cruise control module and ground connection G109.
  3. Turn cruise control switch to ON position. Connect test light between cruise control module harness connector (harness side) terminals "A" (Gray wire) and "E" (Black wire). If test light illuminates, go to next step. If test light does not illuminate, go to step  8 .
  4. Connect test light between cruise control module harness connector terminals "B" (Dark Blue wire) and "E" (Black wire). While observing test light, press and hold cruise control switch in SET/COAST position. If test light illuminates, go to next step. If test light does not illuminate, check for a poor connection, open or short to ground in Dark Blue wire between cruise control module and multifunction lever. If Dark Blue wire is okay, replace multifunction lever. See appropriate STEERING COLUMN SWITCHES article.
  5. Connect test light between cruise control module harness connector terminals "C" (Gray/Black wire) and "E" (Black wire). While observing test light, press and hold cruise control switch in SET/COAST position. If test light does not illuminate, go to next step. If test light illuminates, check for a short between Dark Blue wire and Gray/Black wire between multifunction lever and cruise control module. Repair wiring as necessary. If Gray/Black wire is okay, replace multifunction lever. See appropriate STEERING COLUMN SWITCHES article.
  6. Check voltage between cruise control module harness connector terminals "D" (Brown wire) and "E" (Black wire). If 12 volts exists, go to next step. If 12 volts does not exist, go to step  10 .
  7. Connect test light between cruise control module harness connector terminals "B" (Dark Blue wire) and "E" (Black wire). If test light does not illuminate, go to step  13 . If test light illuminates, check for a short to power on Dark Blue wire between cruise control module and multifunction lever. If Dark Blue wire is okay, replace multifunction lever. See appropriate STEERING COLUMN SWITCHES article.
  8. Connect a test light between cruise control module harness connector terminals "B" (Dark Blue wire) and "E" (Black wire). While observing test light, press and hold cruise control switch in SET/COAST position. If test light illuminates, go to next step. If test light does not illuminate, check for a poor connection or open circuit in Pink wire between multifunction lever and splice S165. If Pink wire is okay, replace multifunction lever. See appropriate STEERING COLUMN SWITCHES article.
  9. Check for a poor connection or open circuit in Gray wire between cruise control module and multifunction lever. If Gray wire is okay, replace multifunction lever. See appropriate STEERING COLUMN SWITCHES article.
  10. Disconnect cruise control release switch connector. Using DVOM, measure voltage between cruise control release switch connector (harness side) terminal "B" (Pink wire on A/T; Brown/White on M/T) and ground. If battery voltage is not present, go to next step. If battery voltage is present, check for poor connection or open in Brown wire between cruise control release switch and cruise control module. Also, check cruise control release switch for correct alignment. If Brown wire and switch alignment are okay, replace cruise control release switch. See CRUISE CONTROL RELEASE SWITCH & BRAKE SWITCH  under REMOVAL & INSTALLATION.
  11. Disconnect wiring harness connector C250 (located near brake pedal support) between cruise control release switch and cruise control module. Using DVOM, measure voltage between connector C250 terminal "B" (Pink wire) and ground. If battery voltage is present, go to next step. If battery voltage is not present, repair open in Pink wire between connector C250 and underhood electrical center No. 2.
  12. On A/T models, repair poor connection or open in Pink wire between connector C250 and cruise control release switch. On M/T models, check for poor connection or open in Pink wire between connector C250 and cruise control release switch. Check for poor connection or open in Brown/White wire between cruise control clutch anticipate switch and cruise control release switch. If Pink wire and Brown/White wire are okay, replace cruise control clutch anticipate switch. See CRUISE CONTROL CLUTCH ANTICIPATE SWITCH & CRUISE CONTROL CLUTCH SWITCH  under REMOVAL & INSTALLATION.
  13. Using test light, probe cruise control module harness connector (harness side) terminals "C" (Gray/Black wire) and "E" (Black wire). If test light does not illuminate, go to next step. If test light illuminates, check for a short to battery voltage in Gray/Black wire between cruise control module and multifunction lever. If Gray/Black wire is okay, replace multifunction lever. See appropriate STEERING COLUMN SWITCHES article.
  14. Set parking brake. Raise drive wheels. Using DVOM, measure voltage between cruise control module harness connector (harness side) terminal "K" (Dark Green/White wire) and ground. While observing DVOM, rotate drive wheels by hand. If voltage fluctuates between zero and 5 volts, go to next step. If voltage does not fluctuate between zero and 5 volts, check for poor connection or open in Dark Green/White wire between cruise control module and PCM.
  15. Turn ignition off. Check for a poor connection or open in Dark Green wire between PCM and cruise control module. Reconnect cruise control module harness connector. Connect scan tool to Data Link Connector (DLC). Start engine. Clear any existing Diagnostic Trouble Codes (DTCs). Using scan tool, monitor SMCC INHIBITED display. Attempt to operate vehicle in cruise control mode. If SMCC INHIBITED is not displayed on scan tool, go to next step. If SMCC INHIBITED is displayed on scan tool, go to step  17 .
  16. Clear any existing DTCs. Using scan tool, select MODE 4 DIAGNOSTICS. Using scan tool, command SMCC to ALLOW cruise. Using DVOM connected to battery voltage, probe cruise control module harness connector (harness side) terminal "H" (Dark Green wire). If battery voltage is present, replace cruise control module. See CRUISE CONTROL MODULE  under REMOVAL & INSTALLATION. If battery voltage is not present, check for a short to voltage in Dark Green wire between cruise control module and PCM. If Dark Green wire is okay, check PCM. Perform appropriate ON-BOARD DIAGNOSTICS (OBD) SYSTEM CHECK. See SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
  17. Using scan tool, monitor the following parameters:
    • Vehicle speed sensor should be 25-100 MPH.
    • Trans range should be 2nd, 3rd or 4th gear.
    • System voltage should be 9-17 volts.
    • Engine speed should be 500-5400 RPM.

    If above parameters are within range, perform appropriate ON-BOARD DIAGNOSTICS (OBD) SYSTEM CHECK. See SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. If previously listed parameters are not within range, check PCM. See appropriate ON-BOARD DIAGNOSTICS (OBD) SYSTEM CHECK under SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.

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