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Checking Speed Control Performance

NOTE: Perform this test only if there are no Diagnostic Trouble Codes (DTC).
  1. Turn ignition on. Using scan tool, monitor cruise control switch inputs. While observing display, press brake pedal several times. If scan tool displays brake switch PRESSED and RELEASED, go to next step. If scan tool does not display brake switch PRESSED and RELEASED, go to step  13.
  2. While observing scan tool display, press ON/OFF switch several times. If scan tool does not display ON/OFF switch PRESSED and RELEASED, go to step  34. If scan tool displays ON/OFF switch PRESSED and RELEASED, inspect wiring and connectors. Repair as necessary. Perform TEST VER-4A  under VERIFICATION TESTS. If wiring and connectors are okay, go to next step.
  3. Turn ignition off. Disconnect cruise control servo. Inspect connectors and terminals for good contact. Clean or repair as necessary. Using a DVOM, measure resistance between ground and cruise control servo connector terminal No. 4 (Black wire). See Figure. If resistance is 5 ohms or more, repair open ground circuit. Perform TEST VER-4A  under VERIFICATION TESTS. If resistance is less than 5 ohms, go to next step.
  4. Turn ignition on. Using scan tool, monitor Park/Neutral Position (PNP) switch inputs. While observing display, shift transmission into Drive. If scan tool does not display PNP switch status as D/R, go to NTC-2: CHECKING PARK/NEUTRAL SWITCH OPERATION . If scan tool displays PNP switch status as D/R, inspect throttle cable and linkage. Repair as necessary. Perform TEST VER-4A  under VERIFICATION TESTS. If throttle cable and linkage are okay, go to next step.
  5. Using scan tool, monitor cruise control switch inputs. While observing scan tool, press SET switch several times. If scan tool does not display SET switch PRESSED and RELEASED, replace left cruise control switch. Perform TEST VER-4A  under VERIFICATION TESTS. If scan tool displays SET switch PRESSED and RELEASED, go to next step.
  6. Using scan tool, monitor cruise control switch inputs. While observing scan tool, press RESUME switch several times. If scan tool displays RESUME switch PRESSED and RELEASED, go to next step. If scan tool does not display RESUME switch PRESSED and RELEASED, go to step  9.
  7. Using scan tool, monitor cruise control switch inputs. While observing scan tool, press CANCEL switch several times. If scan tool does not display CANCEL switch PRESSED and RELEASED, replace right cruise control switch. Perform TEST VER-4A  under VERIFICATION TESTS. If scan tool displays CANCEL switch PRESSED and RELEASED, go to next step.
  8. While observing scan tool, press COAST switch. If scan tool does not display COAST switch PRESSED and RELEASED, replace right cruise control switch. Perform TEST VER-4A  under VERIFICATION TESTS. If scan tool displays COAST switch PRESSED and RELEASED, go to step  21.
  9. Turn ignition off. Disconnect RESUME/ACCEL switch. Turn ignition on. Using scan tool, read cruise control switch voltage. If reading is 4.2 volts or less, go to next step. If reading is more than 4.2 volts, replace right cruise control switch. Perform TEST VER-4A  under VERIFICATION TESTS.
  10. Allow engine to idle for one minute. Turn engine off. Turn ignition on (engine off). Using scan tool, actuate cruise control servo solenoids. If throttle does not open and close, go to VACUUM SUPPLY  test under COMPONENT TESTS. Repair as necessary. Perform TEST VER-4A  under VERIFICATION TESTS. If throttle opens and closes, go to next step.
  11. At this time, speed control switch and servo functions appear to operate properly. Using scan tool, monitor CRUISE CONTROL OUTPUT STATUS. Road test vehicle at speed greater than 35 MPH and attempt to set cruise control. If cruise control does not set, CRUISE CONTROL DENIED STATUS message will indicate reason for cruise control not to set. See SCAN TOOL DENIED STATUS  table. Repair as necessary. If cruise control sets, press continue on scan tool and go to next step.
  12. Turn ignition off. Disconnect RESUME/ACCEL switch. Inspect connectors and terminals for good contact. Clean or repair as necessary. Using a DVOM, measure resistance of Black/Light Blue wire between ground and RESUME/ACCEL switch connector. If resistance is 5 ohms or more, repair open in Black/Light Blue wire. Perform TEST VER-4A  under VERIFICATION TESTS. If resistance is less than 5 ohms, go to step  30.
  13. While observing scan tool display, press ON/OFF switch several times. If scan tool does not display ON/OFF switch PRESSED and RELEASED, go to step  34. If scan tool displays ON/OFF switch PRESSED and RELEASED, inspect wiring and connectors. Repair as necessary. Perform TEST VER-4A  under VERIFICATION TESTS. If wiring and connectors are okay, go to next step.
  14. Turn ignition off. Disconnect cruise control servo. Inspect connectors and terminals for good contact. Clean or repair as necessary. Using a DVOM, measure resistance between ground and cruise control servo connector terminal No. 4 (Black wire). See Figure. If resistance is 5 ohms or more, repair open ground circuit. Perform TEST VER-4A  under VERIFICATION TESTS. If resistance is less than 5 ohms, go to next step.
  15. Turn ignition on. Using scan tool, monitor P/N switch inputs. While observing display, shift transmission into Drive. If scan tool displays P/N switch status as D/R or if scan tool does not display P/N switch status as D/R, go to next step.
  16. Turn ignition off. Inspect throttle cable and linkage for binding or damage. If throttle cable and linkage are not faulty, go to next step. If throttle cable and linkage are faulty, repair as necessary. Go to NTC-2: CHECKING PARK/NEUTRAL SWITCH OPERATION . Perform TEST VER-4A  under VERIFICATION TESTS.
  17. While observing scan tool, press SET switch several times. If scan tool does not display SET switch PRESSED and RELEASED, replace left cruise control switch. Perform TEST VER-4A  under VERIFICATION TESTS. If scan tool displays SET switch PRESSED and RELEASED, turn ignition off and inspect throttle cable and linkage for binding or damage. Repair as necessary. If throttle cable and linkage are not faulty, go to next step.
  18. Turn ignition on. Using scan tool, monitor cruise control switch inputs. While observing scan tool, press RESUME switch several times. If scan tool displays RESUME switch PRESSED and RELEASED, go to next step. If scan tool does not display RESUME switch PRESSED and RELEASED, go to step  26.
  19. While observing scan tool, press CANCEL switch several times. If scan tool does not display CANCEL switch PRESSED and RELEASED, replace right cruise control switch. Perform TEST VER-4A  under VERIFICATION TESTS. If scan tool displays CANCEL switch PRESSED and RELEASED, go to next step.
  20. While observing scan tool, press COAST switch. If scan tool does not display COAST switch PRESSED and RELEASED, replace right cruise control switch. Perform TEST VER-4A  under VERIFICATION TESTS. If scan tool displays COAST switch PRESSED and RELEASED, go to next step.
  21. Let engine idle for one minute. Turn engine off. Turn ignition on (engine off). Using scan tool, actuate cruise control servo solenoids. If throttle does not open and close, go to VACUUM SUPPLY  test under COMPONENT TESTS. Repair as necessary. Perform TEST VER-4A  under VERIFICATION TESTS. If throttle opens and closes, go to next step.
  22. At this time cruise control switch and servo functions appear to be operating properly. Using scan tool, monitor CRUISE CONTROL OUTPUT STATUS. Road test vehicle at speed greater than 35 MPH and attempt to set cruise control. If cruise control does not set, CRUISE CONTROL DENIED STATUS MESSAGE will indicate reason for cruise control malfunction. See SCAN TOOL DENIED STATUS  table. Repair as necessary.
  23. Turn ignition off. Disconnect both cruise control switches. Using a DVOM, measure resistance of Red/Light Green wire between cruise control ON/OFF switch connector and RESUME/ACCEL switch connector. If resistance is 5 ohms or more, repair open in Red/Light Green wire. Perform TEST VER-4A  under VERIFICATION TESTS. If resistance is less than 5 ohms, go to next step.
  24. Turn ignition off. Disconnect RESUME/ACCEL switch. Inspect connectors and terminals for good contact. Clean or repair as necessary. Using a DVOM, measure resistance of Black/Light Blue wire between ground and RESUME/ACCEL switch connector. If resistance is 5 ohms or more, repair open in Black/Light Blue wire. Perform TEST VER-4A  under VERIFICATION TESTS. If resistance is less than 5 ohms, go to next step.
  25. Connect a jumper wire between RESUME/ACCEL switch connector terminals. Turn ignition on. Using scan tool, read cruise control switch voltage. If voltage is less than one volt, replace right cruise control switch. Perform TEST VER-4A  under VERIFICATION TESTS. If voltage is one volt or more, test is complete.
  26. Turn ignition off. Disconnect RESUME/ACCEL switch. Using scan tool, read cruise control switch voltage. If voltage is more than 4.2 volts, replace right cruise control switch. Perform TEST VER-4A  under VERIFICATION TESTS. If voltage is 4.2 volts or less, go to next step.
  27. Turn ignition off. Ensure RESUME/ACCEL switch is disconnected. Inspect connectors and terminals for good contact. Clean or repair as necessary. Using a DVOM, measure resistance of Black/Light Blue wire between ground and RESUME/ACCEL switch connector. If resistance is 5 ohms or more, repair open in Black/Light Blue wire. Perform TEST VER-4A  under VERIFICATION TESTS. If resistance is less than 5 ohms, go to next step.
  28. Let engine idle for one minute. Turn engine off. Turn ignition on (engine off). Using scan tool, actuate cruise control servo solenoids. If throttle does not open and close, go to VACUUM SUPPLY  test under COMPONENT TESTS. Repair as necessary. Perform TEST VER-4A  under VERIFICATION TESTS. If throttle opens and closes, go to next step.
  29. At this time cruise control switch and servo functions appear to be operating properly. Using scan tool, monitor CRUISE CONTROL OUTPUT STATUS. Road test vehicle at speed greater than 35 MPH and attempt to set cruise control. If cruise control does not set, CRUISE CONTROL DENIED STATUS message will indicate reason for cruise control malfunction. See SCAN TOOL DENIED STATUS  table. Repair as necessary.
  30. Turn ignition off. Disconnect both cruise control switches. Using a DVOM, measure resistance of Red/Light Green wire between cruise control ON/OFF switch connector and RESUME/ACCEL switch connector. If resistance is 5 ohms or more, repair open in Red/Light Green wire. Perform TEST VER-4A  under VERIFICATION TESTS. If resistance is less than 5 ohms, go to next step.
  31. Connect a jumper wire between RESUME/ACCEL switch connector terminals. Turn ignition on. Using scan tool, read cruise control switch voltage. If voltage is less than one volt, replace right cruise control switch. Perform TEST VER-4A  under VERIFICATION TESTS. If voltage is one volt or more, go to next step.
  32. While observing scan tool, press CANCEL switch several times. If scan tool does not display CANCEL switch PRESSED and RELEASED, replace right cruise control switch. Perform TEST VER-4A  under VERIFICATION TESTS. If scan tool displays CANCEL switch PRESSED and RELEASED, go to next step.
  33. While observing scan tool, press COAST switch. If scan tool does not display COAST switch PRESSED and RELEASED, replace right cruise control switch. Perform TEST VER-4A  under VERIFICATION TESTS. If scan tool displays COAST switch PRESSED and RELEASED, go to next step.
  34. Turn ignition off. Inspect connectors and terminals for good contact. Clean or repair as necessary. Perform TEST VER-4A  under VERIFICATION TESTS. If no problems exist, go to next step.
  35. Disconnect cruise control servo. Inspect connectors and terminals for good contact. Clean or repair as necessary. Using a DVOM, measure resistance between ground and cruise control servo connector terminal No. 4 (Black wire). See Figure. If resistance is 5 ohms or more, repair open ground circuit. Perform TEST VER-4A  under VERIFICATION TESTS. If resistance is less than 5 ohms, go to next step.
  36. Disconnect ON/OFF switch. Turn ignition on. Using scan tool, read cruise control switch voltage. If voltage is more than 4.2 volts, replace left cruise control switch. Perform TEST VER-4A  under VERIFICATION TESTS. If voltage is 4.2 volts or less, go to next step.
  37. Turn engine off. Turn ignition on. Using scan tool, monitor P/N switch inputs. While observing display, shift transmission into Drive. If scan tool does not display P/N switch status as D/R, go to NTC-2: CHECKING PARK/NEUTRAL SWITCH OPERATION . Inspect throttle cable and linkage. Repair as necessary. Perform TEST VER-4A  under VERIFICATION TESTS. If scan tool displays P/N switch status as D/R, inspect throttle cable and linkage. Repair as necessary. Perform TEST VER-4A  under VERIFICATION TESTS.
  38. Start engine and let idle for one minute. Turn engine off. Turn ignition on, (engine off). Using scan tool, actuate cruise control servo solenoids. If throttle does not open and close, go to VACUUM SUPPLY  test under COMPONENT TESTS. If throttle opens and closes, go to next step.
  39. At this time cruise control switch and servo functions appear to be operating properly. Using scan tool, monitor CRUISE CONTROL OUTPUT STATUS. Road test vehicle at speed greater than 35 MPH and attempt to set cruise control. If cruise control does not set, CRUISE CONTROL DENIED STATUS message will indicate reason for cruise control malfunction. See SCAN TOOL DENIED STATUS  table. Repair as necessary.
SCAN TOOL DENIED STATUS

Denied Message Reason
ON/OFF PCM Does Not Detect ON Signal From Switch At PCM Terminal No. 41
SPEED PCM Detects Vehicle Speed Less Than 36 MPH At Terminal No. 66
RPM Engine RPM Is Excessively High
BRAKE Brake Switch Sense Circuit Is Open Indicating Brakes Applied
P/N Park/Neutral Switch Sense Circuit Is Grounded Indicating Transmission In Park Or Neutral
RPM/SPD PCM Detects Excessive Engine RPM For A Given Vehicle Speed
SOL FLT PCM Detects A Servo Solenoid Circuit Trouble Code Maturing Or Set In Memory
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