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Pinpoint Test C: The Speed Control Is Inoperative - No DTCs

WARNING: This page is about a different car, the 2004 Mercury Monterey and 2004 Ford Freestar. However, it is still accessible from the selected car via links, so may be relevant.
  1. C1 CHECK THE HORN SYSTEM 
    • Verify the horn system operates by pressing the horn switch.
    • Does the horn system operate correctly? 

    Yes 

    GO to C2

    No 

    Refer to INFORMATION, GAUGES & WARNING DEVICES to diagnose the horn system.

  2. C2 CHECK THE SPEED CONTROL ON SWITCH 
    • Key in OFF position.
    • Disconnect: Speed Control Actuator C122.
    • Key in ON position.
    • Measure the voltage between the speed control actuator C122-5, circuit 151 (LB/BK), harness side and ground while pressing the speed control ON switch.
      Fig 1: Checking Speed Control On Switch
      G03245266Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 

    Yes 

    GO to C3.

    No 

    GO to  C4.

  3. C3 CHECK THE SET/ACCEL SWITCH 
    • Key in OFF position.
    • Measure the resistance between the speed control actuator C122-5, circuit 151 (LB/BK), harness side and the speed control actuator C122-6, circuit 848 (DG/OG), harness side while pressing the speed control SET/ACCEL switch.
      Fig 2: Measuring Resistance Between Speed Control Actuator C122-5, Circuit 151 (LB/BK), Harness Side And Speed Control Actuator C122-6, Circuit 848 (DG/OG), Harness Side
      G03245267Courtesy of FORD MOTOR CO.
    • Is the resistance between 612-748 ohms with the switch pressed and greater than 10,000 ohms with the switch released? 

    Yes 

    GO to  C6.

    No 

    INSTALL a new speed control switch. Refer to SPEED CONTROL SWITCH - WITH REMOTE AUDIO CONTROLS  or SPEED CONTROL SWITCH - WITHOUT REMOTE AUDIO CONTROLS . CLEAR the DTCs. REPEAT the self-test.

  4. C4 CHECK CIRCUIT 151 (LB/BK) FOR AN OPEN 
    • Disconnect: Clockspring C218b.
    • Measure the resistance between the speed control actuator C122-5, circuit 151 (LB/BK), harness side and the clockspring C218b-6, circuit 151 (LB/BK), harness side.
      Fig 3: Measuring Resistance Between Speed Control Actuator C122-5, Circuit 151 (LB/BK), Harness Side And Clockspring C218B-6, Circuit 151 (LB/BK), Harness Side
      G03245268Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 

    Yes 

    GO to C5.

    No 

    REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.

  5. C5 CHECK THE CLOCKSPRING 
    • Remove the driver air bag. Refer to DRIVER-SIDE AIR BAG MODULE .
    • Measure the resistance between the clockspring C218b-6, circuit 151 (LB/BK), component side and the upper clockspring-1, component side.
      Fig 4: Measuring Resistance Between Clockspring C218B-6, Circuit 151 (LB/BK), Component Side And Upper Clockspring-1, Component Side
      G03245269Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 

    Yes 

    INSTALL a new speed control switch. Refer to SPEED CONTROL SWITCH - WITH REMOTE AUDIO CONTROLS  or SPEED CONTROL SWITCH - WITHOUT REMOTE AUDIO CONTROLS . INSTALL the driver air bag. Refer to DRIVER-SIDE AIR BAG MODULE . CLEAR the DTCs. REPEAT the self-test.

    No 

    INSTALL a new clockspring. Refer to CLOCKSPRING . INSTALL the driver air bag. Refer to DRIVER-SIDE AIR BAG MODULE . CLEAR the DTCs. REPEAT the self-test.

  6. C6 CHECK CIRCUIT 601 (LB/PK) AND CIRCUIT 535 (LB/RD) FOR VOLTAGE 
    • Key in ON position.
    • Measure the voltage between the speed control actuator C122-7, circuit 601 (LB/PK), harness side and ground; and between the speed control actuator C122-9, circuit 535 (LB/RD), harness side and ground.
      Fig 5: Checking Circuit 601 (LB/PK) And Circuit 535 (LB/RD) For Voltage
      G03245270Courtesy of FORD MOTOR CO.
    • Are the voltages greater than 10 volts? 

    Yes 

    GO to C7.

    No 

    REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.

  7. C7 CHECK CIRCUIT 1205 (BK) FOR AN OPEN 
    • Key in OFF position.
    • Measure the resistance between speed control actuator C122-10, circuit 1205 (BK), harness side and ground.
      Fig 6: Measuring Resistance Between Speed Control Actuator C122-10, Circuit 1205 (BK), Harness Side And Ground
      G03245271Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 

    Yes 

    GO to C8.

    No 

    REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.

  8. C8 CHECK FOR CORRECT SPEED CONTROL ACTUATOR OPERATION 
    • Disconnect the speed control actuator connector.
    • Check for:
      • corrosion
      • pushed-out pins
    • Connect the speed control actuator connector and make sure it seats correctly.
    • Operate the system and verify the concern is still present.
    • Is the concern still present? 

    Yes 

    INSTALL a new speed control actuator. Refer to SPEED CONTROL ACTUATOR . CLEAR the DTCs. REPEAT the self-test.

    No 

    The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.

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