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Pinpoint Test A: The Speed Control Is Inoperative

  1. A1 CHECK THE SPEED CONTROL SERVO VOLTAGE AND GROUND 
    • Key in OFF position.
    • Disconnect: Speed Control Servo C122.
    • Key in ON position.
    • Measure the voltage between speed control servo C122 Pin 7, Circuit 294 (WH/LB), harness side and speed control servo C122 Pin 10, Circuit 1205 (BK), harness side.
      Fig 1: Checking Speed Control Servo Voltage And Ground
      G03242126Courtesy of FORD MOTOR CO.
    • Is voltage greater than 10 volts? 
    1. Yes:  GO to  A3.
    2. No:  GO to A2.
  2. A2 CHECK THE CIRCUIT 1205 (BK) FOR AN OPEN 
    • Key in OFF position.
    • Measure the resistance between speed control servo C122 Pin 10, Circuit 1205 (BK), harness side and ground.
      Fig 2: Checking Circuit 1205 (BK) For An Open
      G03242127Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    1. Yes:  REPAIR Circuit 294 (WH/LB). TEST the system for normal operation.
    2. No:  REPAIR Circuit 1205 (BK). TEST the system for normal operation.
  3. A3 CHECK DEACTIVATOR SWITCH CIRCUITRY 
    • Measure the voltage between speed control servo C122 Pin 9, Circuit 636 (OG), harness side and speed control servo C122 Pin 10, Circuit 1205 (BK), harness side.
      Fig 3: Checking Deactivator Switch Circuitry
      G03242128Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 
    1. Yes:  GO to  A6.
    2. No:  GO to A4.
  4. A4 CHECK CIRCUIT 10 (LG/RD) FOR AN OPEN 
    • Disconnect: Deactivator Switch C2210.
    • Measure the voltage between deactivator switch C2210 Pin 1, Circuit 10 (LG/RD), harness side and ground.
      Fig 4: Checking Circuit 10 (LG/RD) For Open
      G03242129Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 
    1. Yes:  GO to A5.
    2. No:  REPAIR the circuit. TEST the system for normal operation.
  5. A5 CHECK CIRCUIT 636 (OG) FOR AN OPEN 
    • Measure the resistance between speed control servo C122 Pin 9, Circuit 636 (OG), harness side and deactivator switch C2210 Pin 2, Circuit 636 (OG), harness side.
      Fig 5: Checking Circuit 636 (OG) For Open
      G03242130Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    1. Yes:  INSTALL a new deactivator switch. REFER to SWITCH - DEACTIVATOR . TEST the system for normal operation.
    2. No:  REPAIR the circuit. TEST the system for normal operation.
  6. A6 CHECK THE SPEED CONTROL ACTUATOR SWITCH ON CIRCUITRY 
    • Measure the voltage between speed control servo C122 Pin 5, Circuit 151 (LB/BK), harness side and speed control servo C122 Pin 10, Circuit 1205 (BK), harness side, while the speed control actuator switch ON is pressed.
      Fig 6: Checking Speed Control Actuator Switch On Circuitry
      G03242131Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 
    1. Yes:  GO to  A9.
    2. No:  GO to A7.
  7. A7 CHECK CIRCUIT 151 (LB/BK) FOR AN OPEN 
    • Disconnect: Air Bag Sliding Contact C218a.
    • Measure the resistance between speed control servo C122 Pin 5, Circuit 151 (LB/BK), harness side and air bag sliding contact C218a Pin 4, Circuit 151 (LB/BK), harness side.
      Fig 7: Checking Circuit 151 (LB/BK) For Open
      G03242132Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    1. Yes:  GO to A8.
    2. No:  REPAIR the circuit. TEST the system for normal operation.
  8. A8 CHECK THE AIR BAG SLIDING CONTACT 
    • Remove the driver air bag. Refer to AIR BAG RESTRAINT SYSTEMS .
    • Disconnect: Speed Control Actuator Switch.
    • Measure the resistance between bottom of air bag sliding contact Pin 1 (component side) and top of air bag sliding contact Pin 3 (component side).
      Fig 8: Checking Air Bag Sliding Contact
      G03242133Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    1. Yes:  INSTALL a new speed control actuator switch. REFER to SWITCH - SPEED CONTROL ACTUATOR . INSTALL the driver air bag. REFER to AIR BAG RESTRAINT SYSTEMS . TEST the system for normal operation.
    2. No:  INSTALL a new air bag sliding contact. REFER to AIR BAG RESTRAINT SYSTEMS . INSTALL the driver air bag. REFER to AIR BAG RESTRAINT SYSTEMS . TEST the system for normal operation.
  9. A9 CHECK THE SPEED CONTROL ACTUATOR SWITCH ON CIRCUITRY FOR SHORT TO POWER 
    • Key in ON position.
    • Measure the voltage between speed control servo C122 Pin 5, Circuit 151 (LB/BK), harness side and speed control servo C122 Pin 10, Circuit 1205 (BK), harness side.
      Fig 9: Checking Speed Control Actuator Switch On Circuitry For Short To Power
      G03242134Courtesy of FORD MOTOR CO.
    • Is any voltage present? 
    1. Yes:  GO to A10.
    2. No:  GO to  A12.
  10. A10 CHECK CIRCUIT 151 (LB/BK) FOR SHORT TO POWER 
    • Key in OFF position.
    • Disconnect: Air Bag Sliding Contact C218a.
    • Key in ON position.
    • Measure the voltage between speed control servo C122 Pin 5, Circuit 151 (LB/BK), harness side and speed control servo C122 Pin 10, Circuit 1205 (BK), harness side.
      Fig 10: Checking Circuit 151 (LB/BK) For Short To Power
      G03242135Courtesy of FORD MOTOR CO.
    • Is any voltage present? 
    1. Yes:  REPAIR the circuit. TEST the system for normal operation.
    2. No:  GO to A11.
  11. A11 CHECK THE AIR BAG SLIDING CONTACT 
    • Key in OFF position.
    • Remove the driver air bag. Refer to AIR BAG RESTRAINT SYSTEMS .
    • Connect: Restraint System Diagnostic Tool 418-F088 (105-R0012) or Equivalent.
    • Connect the battery. Refer to BATTERY, MOUNTING AND CABLES .
    • Disconnect: Speed Control Actuator Switch.
    • Key in ON position.
    • Measure the voltage between bottom of air bag sliding contact Pin 1 (component side) and ground.
      Fig 11: Checking Air Bag Sliding Contact
      G03242136Courtesy of FORD MOTOR CO.
    • Is any voltage present? 
    1. Yes:  INSTALL a new air bag sliding contact. REFER to AIR BAG RESTRAINT SYSTEMS . DISCONNECT the battery. REFER to BATTERY, MOUNTING AND CABLES . INSTALL the driver air bag. REFER to AIR BAG RESTRAINT SYSTEMS . TEST the system for normal operation.
    2. No:  INSTALL a new speed control actuator switch. REFER to SWITCH - SPEED CONTROL ACTUATOR . DISCONNECT the battery. REFER to BATTERY, MOUNTING AND CABLES . INSTALL the driver air bag. REFER to AIR BAG RESTRAINT SYSTEMS . TEST the system for normal operation.
  12. A12 CHECK THE SPEED CONTROL ACTUATOR SET/ACCEL CIRCUITRY 
    • Key in OFF position.
    • Measure the resistance between speed control servo C122 Pin 5, Circuit 151 (LB/BK), harness side and speed control servo C122 Pin 6, Circuit 848 (DG/OG), harness side, while the speed control actuator switch SET/ACCEL is pressed.
      Fig 12: Checking Speed Control Actuator Set/Accel Circuitry
      G03242137Courtesy of FORD MOTOR CO.
    • Is the resistance between 612 and 748 ohms? 
    1. Yes:  GO to A13.
    2. No:  INSTALL a new speed control actuator switch. REFER to SWITCH - SPEED CONTROL ACTUATOR . TEST the system for normal operation.
  13. A13 CHECK THE BPP SWITCH CIRCUITRY 
    • Measure the resistance between speed control servo C122 Pin 4, Circuit 511 (LG), harness side, and speed control servo C122 Pin 10, Circuit 1205 (BK), harness side.
      Fig 13: Checking BPP Switch Circuitry
      G03242138Courtesy of FORD MOTOR CO.
    • Is the resistance less than 20 ohms? 
    1. Yes:  GO to  A16.
    2. No:  If automatic transmission, REPAIR Circuit 511 (LG) and Circuit 810 (LG/RD) as necessary. TEST the system for normal operation.

      If manual transmission, GO to A14.

  14. A14 CHECK CIRCUIT 511 (LG) AND CIRCUIT 810 (RD/LG) FOR AN OPEN 
    • Disconnect: CPP Switch C2072.
    • Measure the resistance between CPP Switch C2072 Pin 1, Circuit 511 (LG), harness side and ground.
      Fig 14: Checking Circuit 511 (LG) And Circuit 810 (RD/LG) For Open
      G03242139Courtesy of FORD MOTOR CO.
    • Is the resistance less than 20 ohms? 
    1. Yes:  GO to A15.
    2. No:  REPAIR Circuit 511 (LG) and Circuit 810 (LG/RD) as necessary. TEST the system for normal operation.
  15. A15 CHECK CIRCUIT 511 (LG) FOR AN OPEN 
    • Measure the resistance between speed control servo C122 Pin 4, Circuit 511 (LG), harness side and CPP switch C2072 Pin 2, Circuit 511 (LG), harness side.
      Fig 15: Checking Circuit 511 (LG) For Open
      G03242140Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    1. Yes:  INSTALL a new CPP switch. TEST the system for normal operation.
    2. No:  REPAIR the circuit. TEST the system for normal operation.
  16. A16 CHECK CIRCUIT 239 (WH/OG) FOR AN OPEN 
    • Disconnect: PCM C175.
    • Connect EEC-V 104-Pin Breakout Box.
    • Measure the resistance between speed control servo C122 pin 3, circuit 239 (WH/OG), harness side and Breakout Box, EEC-V Control System pin 68, circuit 239 (WH/OG), harness side.
      Fig 16: Checking Circuit 239 (WH/OG) For Open
      G03242141Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    1. Yes:  GO to A17.
    2. No:  REPAIR the circuit. TEST the system for normal operation.
  17. A17 CHECK THE SPEED CONTROL SERVO 
    • INSTALL a known good speed control servo.
    • Test drive the vehicle for correct operation.
    • Does the speed control operate correctly 
    1. Yes:  INSTALL a new speed control servo. REFER to ACTUATOR - SPEED CONTROL SERVO . TEST the system for normal operation.
    2. No:  INSTALL a new PCM. REFER to ELECTRONIC ENGINE CONTROLS . TEST the system for normal operation.
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