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Pinpoint Test A: The Shift Interlock System Does Not Release/Lock Correctly

  1. A1 TEST THE BRAKE LIGHTS 
    • Apply the brake pedal and view the brake lights.
    • Do the brake lights illuminate? 

    Yes:  GO to  A2.

    No:  REFER to EXTERIOR LIGHTING .

  2. A2 TEST FUSE C34 (30A) 
    • Check fuse: Fuse C34 (30A) Power Distribution Box.
    • Is the resistance of the fuse 5 ohms or less? 

    Yes:  GO to  A3.

    No:  REFER to STARTING SYSTEM .

  3. A3 TEST FUSE C18 (10A) 
    • Check fuse: Fuse C18 (10A) Smart Junction Box.
    • Is the resistance of the fuse 5 ohms or less? 

    Yes:  GO to  A4.

    No:  REFER to STARTING SYSTEM .

  4. A4 TEST CIRCUIT 1050 (LG/PK) FOR SHORT TO GROUND 
    • Disconnect: Ignition Switch C250.
    • Measure the resistance between ignition switch C250 pin 1, circuit 1050 (LG/PK) harness side and ground.
      Fig 1: Measuring Resistance Between Ignition Switch C250 Pin 1, Circuit 1050 (LG/PK) Harness Side & Ground
      G04657559Courtesy of FORD MOTOR CO.
    • Is the resistance greater than 10,000 ohms? 

    Yes:  GO to  A5.

    No:  REPAIR circuit 1050 (LG/PK). TEST the system for normal operation.

  5. A5 TEST CIRCUIT 1050 (LG/PK) FOR AN OPEN 
    • Disconnect: Ignition Switch C250.
    • Disconnect: Smart Junction Box (SJB) C2280b.
    • Measure the resistance between SJB C2280b pin 32, circuit 1050 (LG/PK), harness side and ignition switch C250 pin 1, harness side.
      Fig 2: Measuring Resistance Between SJB C2280b Pin 32, Circuit 1050 (LG/PK), Harness Side & Ignition Switch C250 Pin 1, Harness Side
      G04657560Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 

    Yes:  GO to  A6.

    No:  REPAIR circuit 1050 (LG/PK). TEST the system for normal operation.

  6. A6 TEST CIRCUIT 1140e (PK) FOR BATTERY VOLTAGE 
    • Key in OFF position.
    • Disconnect: Brake Pedal Position (BPP) Switch C278.
    • Measure the voltage between BPP switch C278 pin 1, circuit 1140e (PK), harness side and ground.
      Fig 3: Measuring Voltage Between BPP Switch C278 Pin 1, Circuit 1140e (PK), Harness Side & Ground
      G04657561Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 

    Yes:  GO to  A7.

    No:  REPAIR circuit 1140e (PK). TEST the system for normal operation.

  7. A7 TEST CIRCUIT 1140e (PK) FOR A SHORT TO GROUND 
    • Disconnect: Brake Pedal Position (BPP) Switch C278.
    • Measure the resistance between BPP switch C278 pin 2, circuit 1140e (PK), harness side and ground.
      Fig 4: Measuring Resistance Between BPP Switch C278 Pin 2, Circuit 1140e (PK), Harness Side & Ground
      G04657562Courtesy of FORD MOTOR CO.
    • Is the resistance greater than 10,000 ohms? 

    Yes:  GO to  A8.

    No:  REPAIR circuit 1140e (PK). TEST the system for normal operation.

  8. A8 TEST CIRCUIT 1140e (PK) FOR AN OPEN 
    • Disconnect: Smart Junction Box (SJB) C265.
    • Measure the resistance between SJB C2280a pin 27 and BPP switch C278 pin 2, circuit 1140e (PK), harness side.
      Fig 5: Measuring Resistance Between SJB C2280a Pin 27 & BPP Switch C278 Pin 2, Circuit 1140e (PK), Harness Side
      G04657563Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 

    Yes:  GO to  A9.

    No:  REPAIR circuit 1140e (PK). TEST the system for normal operation.

  9. A9 TEST THE BRAKE PEDAL POSITION (BPP) SWITCH 
    • Measure the resistance between BPP switch C278 pin 1 and pin 2, while OPEN (off) and CLOSED (on).
      Fig 6: Measuring Resistance Between BPP Switch C278 Pin 1 & Pin 2, While OPEN (Off) & CLOSED (On)
      G04657564Courtesy of FORD MOTOR CO.
    • Is the resistance of the switch greater than 10,000 ohms while OFF and 5 ohms or less while ON? 

    Yes:  GO to  A10.

    No:  INSTALL a new BPP switch. TEST the system for normal operation.

  10. A10 TEST CIRCUIT 810 (RD/LG) FOR A SHORT TO GROUND 
    • Disconnect: Floor Shifter Harness Assembly C3245.
    • Measure the resistance between floor shifter harness assembly C3245 pin 1, circuit 810 (RD/LG), harness side and ground.
      Fig 7: Measuring Resistance Between Floor Shifter Harness Assembly C3245 Pin 1, Circuit 810 (RD/LG), Harness Side & Ground
      G04657565Courtesy of FORD MOTOR CO.
    • Is the resistance greater than 10,000 ohms? 

    Yes:  GO to  A11.

    No:  REPAIR circuit 810 (RD/LG). TEST the system for normal operation.

  11. A11 TEST CIRCUIT 810 (RD/LG) FOR AN OPEN 
    • Measure the resistance between BPP switch C278 pin 1, circuit 810 (RD/LG), harness side and floor shifter harness assembly C3245 pin 1, circuit 810 (RD/LG), harness side.
      Fig 8: Measuring Resistance Between BPP Switch C278 Pin 1, Circuit 810 (RD/LG), Harness Side & Floor Shifter Harness Assembly C3245 Pin 1, Circuit 810 (RD/LG), Harness Side
      G04657566Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 

    Yes:  GO to  A12.

    No:  REPAIR circuit 810. TEST the system for normal operation.

  12. A12 TEST CIRCUIT 810 (RD/LG) FOR BATTERY VOLTAGE 
    • Connect: Brake Pedal Position (BPP) Switch C278.
    • Disconnect: Floor Shifter Harness Assembly C3245.
    • Depress the brake pedal.
    • Measure the voltage on floor shifter harness assembly C3245 pin 1, circuit 810 (RD/LG), harness side and ground.
      Fig 9: Measuring Voltage On Floor Shifter Harness Assembly C3245 Pin 1, Circuit 810 (RD/LG), Harness Side & Ground
      G04657567Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 

    Yes:  REPAIR circuit 810 (RD/LG). TEST the system for normal operation.

    No:  GO to  A13.

  13. A13 TEST CIRCUIT 409 (TN/BK) FOR A SHORT TO GROUND 
    • Disconnect: Floor Shifter Harness Assembly C3245.
    • Measure the resistance between floor shifter harness assembly C3245 pin 8, circuit 409 (TN/BK), harness side and ground.
      Fig 10: Measure Resistance Between Floor Shifter Harness Assembly C3245 Pin 8, Circuit 409 (TN/BK), Harness Side & Ground
      G04657568Courtesy of FORD MOTOR CO.
    • Is the resistance less than 10,000 ohms? 

    Yes:  REPAIR circuit 409 (TN/BK). TEST the system for normal operation.

    No:  GO to  A14.

  14. A14 TEST CIRCUIT 409 (TN/BK) FOR AN OPEN 
    • Disconnect: Ignition Switch C250.
    • Disconnect: Floor Shifter Harness Assembly C3245.
    • Measure the resistance between floor shifter harness assembly C3245 pin 8, and ignition switch C250 pin 3, circuit 409 (TN/BK), harness side.
      Fig 11: Measuring Resistance Between Floor Shifter Harness Assembly C3245 Pin 8 & Ignition Switch C250 Pin 3, Circuit 409 (TN/BK), Harness Side
      G04657569Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 

    Yes:  REPAIR circuit 409 (TN/BK). TEST the system for normal operation.

    No:  GO to  A15.

  15. A15 TEST CIRCUIT 1205NZ (BK) FOR A SHORT TO GROUND 

Yes:  INSTALL a new selector lever, REFER to SELECTOR LEVER . TEST the system for normal operation.

No:  REPAIR circuit 1205NZ (BK). TEST the system for normal operation.

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