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Test A: Speed Control Is Inoperative

NOTE: Perform all voltage and resistance tests using a Digital Volt-Ohm Meter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in test procedure. Use ohmmeter to isolate wiring harness shorts or opens.
  1. Turn ignition switch to LOCK position. Disconnect speed control servo/actuator 10-pin harness connector C122. See Fig 1. Speed control servo/actuator is located behind left front fenderwell. See Figure. Turn ignition switch to RUN position. Measure voltage between speed control servo/actuator harness connector C122 terminals No. 7 (White/Light Blue wire) and No. 10 (Black wire). Voltage should be 10 volts or more. If voltage is not as specified, go to next step. If voltage is as specified, go to step  3.
  2. Turn ignition switch to LOCK position. Measure resistance between ground and speed control servo/actuator harness connector C122 terminal No. 10 (Black wire). Resistance should be less than 5 ohms. If resistance is more than specified, repair open or short circuit in Black wire between ground and speed control servo/actuator. If resistance is as specified, repair open or short circuit in White/Light Blue wire between speed control servo/actuator and fuse No. 17 (15-amp) in central junction box. Central junction box is located behind left side of instrument panel. See Figure. For CRUISE CONTROLSYSTEMS circuit identification, see WIRING DIAGRAMS . After repair, test system for normal operation.
  3. Leave ignition switch in RUN position. Measure voltage between speed control servo/actuator harness connector C122 terminals No. 9 (Orange wire) and No. 10 (Black wire). Voltage should be 10 volts or more. If voltage is not as specified, go to next step. If voltage is as specified, go to step  6.
  4. Turn ignition switch to LOCK position. Disconnect brake pressure switch 2-pin harness connector C277. See Fig 2. Brake pressure switch is located under left side of instrument panel, near brake pedal bracket. See Figure. Turn ignition switch to RUN position. Measure voltage between ground and brake pressure switch harness connector C277 terminal No. 1 (Light Green/Red wire). Voltage should be 10 volts or more. If voltage is as specified, go to next step. If voltage is not as specified, repair open circuit (in Light Green/Red wire) between brake pressure switch and fuse No. 33 (15-amp) in central junction box. Central junction box is located behind left side of instrument panel. See Figure. For CRUISE CONTROLSYSTEMS circuit identification, see WIRING DIAGRAMS . After repair, test system for normal operation.
  5. Turn ignition switch to LOCK position. Measure resistance between brake pressure switch harness connector C277 terminal No. 2 and speed control servo/actuator harness connector C122 terminal No. 9 (Orange wire). See Fig 2 and Fig 1 . Resistance should be less than 5 ohms. If resistance is as specified, replace brake pressure switch. If resistance is not as specified, repair open circuit in Orange wire between brake pressure switch and speed control servo/actuator. For CRUISE CONTROLSYSTEMS circuit identification, see WIRING DIAGRAMS . After repair, test system for normal operation.
  6. Turn ignition switch to RUN position. While pressing speed control switch ON button, measure voltage between speed control servo/actuator harness connector C122 terminals No. 5 (Light Blue/Black wire) and No. 10 (Black wire). Voltage should be 10 volts or more. If voltage is not as specified, go to next step. If voltage is as specified, go to step  9.
  7. Turn ignition switch to LOCK position. Deactivate air bag restraint system. See DISABLING & ACTIVATING AIR BAG SYSTEM in AIR BAG RESTRAINT SYSTEMS article in RESTRAINTS. Disconnect bottom air bag clockspring 4-pin harness connector C218a. See Fig 3. Located underside of steering column. See Figure. Measure resistance between bottom air bag clockspring harness connector C218a terminal No. 4 and speed control servo/actuator harness connector C122 terminal No. 5 (Light Blue/Black wire). Resistance should be less than 5 ohms. If resistance is a specified, go to next step. If resistance is not as specified, repair open circuit in Light Blue/Black wire between bottom air bag clockspring harness connector and speed control servo/actuator. For CRUISE CONTROLSYSTEMS circuit identification, see WIRING DIAGRAMS . After repair, test system for normal operation.
  8. With air bag restraint system deactivated, remove driver's side air bag. See DRIVER-SIDE AIR BAG MODULE under REMOVAL & INSTALLATION in AIR BAG RESTRAINT SYSTEMS article RESTRAINTS. Disconnect top air bag clockspring (speed control switch) 3-pin harness connector C218b. See Fig 4. Measure resistance between bottom air bag clockspring connector 218a terminal No.1 (component side)and top air bag clockspring connector 218b terminal No. 3 (component side). See Fig 5. Resistance should be less than 5 ohms. If resistance is as specified, replace speed control switch assembly. See SPEED CONTROL SWITCH ASSEMBLY  under REMOVAL & INSTALLATION. If resistance is not as specified, replace air bag clockspring. After repair, test system for normal operation.
  9. Turn ignition switch to RUN position. Measure voltage between speed control servo/actuator harness connector C122 terminals No. 5 (Light Blue/Black wire) and No. 10 (Black wire). If any voltage is found, go to next step. If no voltage is found, go to step  12.
  10. Turn ignition switch to LOCK position. Disconnect bottom air bag clockspring harness connector C218a. See Fig 3. Located underside of steering column. See Figure. Turn ignition switch to RUN position. Measure voltage between speed control servo/actuator harness connector C122 terminals No. 5 (Light Blue/Black wire) and No. 10 (Black wire). Voltage should not be found. If no voltage is found, go to next step. If any voltage is found, repair short circuit to voltage in Light Blue/Black wire between speed control servo/actuator and air bag clockspring. For CRUISE CONTROLSYSTEMS circuit identification, see WIRING DIAGRAMS . After repair, test system for normal operation.
  11. Turn ignition switch to LOCK position. Deactivate air bag system and remove driver's side air bag. See DRIVER-SIDE AIR BAG MODULE under REMOVAL & INSTALLATION in AIR BAG RESTRAINT SYSTEMS article RESTRAINTS. Disconnect speed control switch harness connector C218b. See Fig 4. Turn ignition switch to RUN position. Measure voltage between ground and air bag clockspring connector C218a terminal No. 1 (component side). Voltage should not be found. If no voltage is found, replace speed control switch. See SPEED CONTROL SWITCH ASSEMBLY  under REMOVAL & INSTALLATION. If any voltage is found, replace air bag clockspring. See CLOCKSPRING under REMOVAL & INSTALLATION in AIR BAG RESTRAINT SYSTEMS article RESTRAINTS. After repair, test system for normal operation.
  12. Turn ignition switch to LOCK position. While pressing SET/ACCEL button, measure resistance between speed control servo/actuator harness connector C122 terminals No. 5 (Light Blue/Black wire) and No. 6 (Dark Green/Orange wire). See Fig 3 and Fig 4 . Resistance should be 612-748 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace speed control switch. See SPEED CONTROL SWITCH ASSEMBLY  under REMOVAL & INSTALLATION. After repair, test system for normal operation.
  13. Ensure brake lights are operating properly before proceeding. Measure resistance between speed control servo/actuator harness connector C122 terminals No. 4 (Light Green wire) and No. 10 (Black wire). See Fig 1. Resistance should be less than 20 ohms. If resistance is as specified, go to step  17. If resistance is not as specified, for vehicles equip with A/T go to next step. For vehicles equipped with M/T, go to step  15.
  14. Check for open circuit or high resistance in Light Green wire between speed control servo/actuator harness connector C122 terminals No. 4 and fuse No. 35 (15-amp) located in central junction box. Central junction box is located behind left side of instrument panel. See Figure. Also check for open circuit or high resistance in Light Green/Red wire between brake pressure switch harness connector terminal No. 1 and fuse No. 33 (15-amp) located in central junction box. If problem is found, repair as necessary. After repair, test system for normal operation.
  15. Disconnect deactivator switch 2-pin harness connector C2210. See Fig 6. Deactivator switch is located above brake pedal position switch, connected to brake pedal arm. See Figure. Measure resistance between ground and deactivator switch harness connector C2210 terminal No. 1 (Light Green wire). Resistance should be less than 20 ohms. If resistance is as specified, go to next step. If resistance is not as specified, repair open circuit in Light Green wire between speed control servo/actuator and deactivator switch. After repair, test system for normal operation.
  16. Measure resistance between deactivator switch harness connector C2210 terminal No. 2 and speed control servo/actuator harness connector C122 terminal No. 4 (Light Green wire). Resistance should be less than 5 ohms. If resistance is as specified, replace deactivator switch. See DEACTIVATOR SWITCH  under REMOVAL & INSTALLATION. If resistance is not as specified, repair open circuit in Light Green wire between deactivator switch and speed control servo/actuator. For CRUISE CONTROLSYSTEMS circuit identification, see WIRING DIAGRAMS . After repair, test system for normal operation.
  17. Turn ignition switch to LOCK position. Disconnect Powertrain Control Module (PCM) 104-pin harness connector C175. See Fig 7. PCM is located behind passenger's side kick panel. See Figure. Connect EEC-V 104-pin Breakout Box (014-00950) on harness side. Measure resistance between speed control servo/actuator harness connector C122 terminal No. 3 and breakout box terminal No. 68 (White/Orange wire). See Fig 1 and Fig 7 . Resistance should be less than 5 ohms. If resistance is as specified, go to next step. If resistance is not as specified, repair open circuit in White/Orange wire between speed control servo/actuator and PCM. For CRUISE CONTROLSYSTEMS circuit identification, see WIRING DIAGRAMS . After repair, test system for normal operation.
  18. Install known-good speed control servo/actuator. See SERVO/ACTUATOR ASSEMBLY  under REMOVAL & INSTALLATION. Test drive vehicle and check for proper speed control operation. If speed control operates properly, replace speed control servo/actuator. If speed control does not operate properly, replace PCM. See POWERTRAIN CONTROL MODULE  under REMOVAL & INSTALLATION. After repair, test system for normal operation.
Fig 1: Identifying Servo/Actuator Harness Connector C122 Terminals
G96B29331Courtesy of FORD MOTOR CO.
Fig 2: Identifying Brake Pressure Switch Connector C277 Terminals
G00162086Courtesy of FORD MOTOR CO.
Fig 3: Identifying Air Bag Clockspring Connector C218a Terminals
G00162085Courtesy of FORD MOTOR CO.
Fig 4: Identifying Speed Control Switch Connector C218b Terminals
G00162084Courtesy of FORD MOTOR CO.
Fig 5: Testing Air Bag Sliding Contact Resistance
G99H08207Courtesy of FORD MOTOR CO.
Fig 6: Identifying Deactivator switch Or Jumper Connector C2210 Terminals
G00162080Courtesy of FORD MOTOR CO.
Fig 7: Identifying PCM Harness Connector C175 Terminals
G96F31315Courtesy of FORD MOTOR CO.
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