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Home >> Ford >> 2005 >> Excursion 6.0 P, 4WD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Pinpoint Tests - 6.0L Diesel (99P F450/550) >> Pinpoint Test AS: Loss of Communication With The Fuel Injection Control Module (FICM) >> Test Procedure
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Test Procedure

  1. AS1 PRELIMINARY DIAGNOSIS FOR DTC U0105 
    • Retrieve and record all DTCs.
    • Record the freeze frame data.
    • Clear all DTCs.
      NOTE: Listen for fuel injector buzz at the beginning of the on-demand self-test.
    • Carry out the on-demand self-test.

    Is DTC U0105 present? 

    Yes No
    GO to  AS2. UNABLE to duplicate the condition. CHECK for a loose connection, and damaged or corroded terminals. WIGGLE the harness attempting to recreate the fault. REPAIR as necessary. REFER to SYMPTOM CHARTS - 6.0L DIESEL if a driveability concern exists.
  2. AS2 DIAGNOSTIC TROUBLE CODE (DTC) U0105 
    • Possible causes:
      • Loose connectors
      • CAN circuit
      • FICM power circuit
      • FICM ground circuit
      • FICM relay
      • FICM
      • PCM
    • Key OFF.
    • Disconnect the FICM relay.
    • Carry out the relay component test. Refer to COMPONENT TESTING .

    Is the relay OK? 

    Yes No
    GO to  AS3. INSTALL a new FICM relay. CLEAR the DTCs. REPEAT the self-test.
  3. AS3 CHECK THE FICM RELAY VOLTAGE CIRCUITS 
    • Key ON, engine OFF.
    • Measure the voltage between the FICM relay pin 2, harness side and ground; and between the FICM relay pin 5, harness side and ground.

    Are the voltages greater than 10 volts? 

    Yes No
    GO to  AS4. REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
  4. AS4 CHECK THE IGNITION POWER CIRCUIT FOR VOLTAGE 
    • Key OFF.
    • Disconnect the FICM C connector.
    • Key ON, engine OFF.
    • Measure the voltage between the FICM ignition power circuit pin 7, harness side and ground.

    Is the voltage greater than 10 volts? 

    Yes No
    GO to  AS5. REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
  5. AS5 CHECK THE LOGIC POWER CIRCUIT FOR AN OPEN 
    • Key OFF.
    • Measure the resistance between the FICM relay pin 3, harness side and the FICM logic power circuit pin 8, harness side.

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  AS6. REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
  6. AS6 CHECK THE RELAY CONTROL CIRCUIT FOR AN OPEN 
    • Measure the resistance between the FICM relay pin 1, harness side and the FICM relay control circuit pin 27, harness side.

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  AS7. REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
  7. AS7 CHECK THE FICM GROUND CIRCUITS FOR AN OPEN 
    • Measure the resistance between the FICM C connector pins harness side as follows:
      • Pin 1 and ground
      • Pin 2 and ground
      • Pin 3 and ground
      • Pin 22 and ground
      • Pin 26 and ground

    Are the resistances less than 5 ohms? 

    Yes No
    GO to  AS8. REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
  8. AS8 CHECK THE FICM CAN CIRCUITS 
    • Disconnect the PCM engine harness connector.
    • Carry out a visual inspection. Check for loose connections and the CAN circuits wiring shield between the PCM engine harness connector pins 37, 26 and the FICM harness connector pins 30, 31.

    Are the wiring and shield OK? 

    Yes No
    GO to  AS9. REPAIR as necessary. CLEAR the DTCs. REPEAT the self-test.
  9. AS9 CHECK FICM CAN CIRCUITS FOR A SHORT TO VOLTAGE 
    • Key ON, engine OFF.
    • Measure the voltage between the PCM engine harness connector pin 37, harness side and ground; and between the PCM engine harness connector pin 26, harness side and ground.

    Is any voltage indicated? 

    Yes No
    REPAIR the short to voltage. CLEAR the DTCs. REPEAT the self-test. GO to  AS10.
  10. AS10 CHECK THE FICM CAN CIRCUITS FOR A SHORT TOGETHER 
    • Key OFF.
    • Measure the resistance between the PCM engine harness connector pin 37, harness side and the PCM engine harness connector pin 26, harness side.

    Is the resistance greater than 10,000 ohms? 

    Yes No
    GO to  AS11. REPAIR the shorted circuits. CLEAR the DTCs. REPEAT the self-test.
  11. AS11 CHECK FICM CAN CIRCUITS FOR A SHORT TO GROUND 
    • Measure the resistance between the PCM engine harness connector pin 37, harness side and ground; and between the PCM engine harness connector pin 26, harness side and ground.

    Are the resistances greater than 10,000 ohms? 

    Yes No
    GO to  AS12. REPAIR the short to ground. CLEAR the DTCs. REPEAT the self-test.
  12. AS12 CHECK THE FICM CAN CIRCUITS FOR AN OPEN 
    • Measure the resistance between the PCM engine harness connector pin 37 and the FICM harness connector C pin 30; and between the PCM engine harness connector pin 26 and the FICM harness connector C pin 31.

    Are the resistances less than 5 ohms? 

    Yes No
    GO to  AS13. REPAIR the open circuit in question. CLEAR the DTCs. REPEAT the self-test.
  13. AS13 CHECK THE PCM TO FICM COMMUNICATION 
    • Connect the PCM engine harness connector.
    • Connect the FICM harness connector C.
    • Key ON, engine OFF.
    • Access the PCM.
    • Monitor the FICM LPWR, FICM MPWR, and FICM VPWR PIDs. Refer to for REFERENCE VALUES - EXCURSION (6.0L DIESEL) .

    Do the PIDs indicate correctly? 

    Yes No
    INSTALL a new PCM. CLEAR the DTCs. REPEAT the self-test. INSTALL a new FICM. CLEAR the DTCs. REPEAT the self-test.
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