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Home >> Ford >> 2006 >> Focus ZX5 SE, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 126 (Engine Controls - Pinpoint Tests - 6.0L Diesel (99P F450/550)) >> Pinpoint Test AX: Exhaust Gas Recirculation Throttle Control >> Test Procedure

Test Procedure

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  1. AX1 PRELIMINARY DIAGNOSIS 

    Key on, engine off.

    Access the PCM.

    Retrieve and record the DTCs.

    Are there any DTCs present?

    Yes  No 
    For DTC P0407, GO to AX2 
    For DTC P0408, GO to  AX7
    For DTC P0487, GO to  AX11
    For DTC P0488, GO to  AX16
    For DTC P1334, GO to  AX19    		 GO to   AX16
  2. AX2 PRELIMINARY DIAGNOSIS FOR DTC P0407 

    Possible causes:

    • signal circuit open or short to ground
    • VREF circuit open
    • EGRTP sensor
    • PCM

    Key off.

    Disconnect the EGRTP sensor.

    Connect a 5 amp fused jumper wire between the EGRTP sensor VREF circuit pin A, harness side and the EGRTP sensor signal circuit pin C, harness side.

    Key on, engine off.

    Access the EGRTP_V PID

    Is the EGRTP_V PID voltage greater than 4.5 volts?

    Yes  No 
    INSTALL a new EGRTP sensor GO to AX3 
  3. AX3 CHECK THE VREF CIRCUIT FOR VOLTAGE 

    Measure the voltage between the EGRTP sensor VREF circuit pin A, harness side and ground.

    Is the voltage greater than 4.5 volts?

    Yes  No 
    GO to AX4  REPAIR the circuit.
  4. AX4 CHECK THE SIGNAL CIRCUIT FOR AN OPEN 

    Key off

    Disconnect the PCM engine harness connector.

    Measure the resistance between the EGRTP sensor signal circuit pin C, harness side and the PCM engine connector pin 38 harness side

    Is the resistance less than 5 ohms?

    Yes  No 
    GO to AX5  REPAIR the circuit.
  5. AX5 CHECK THE SIGNAL CIRCUIT FOR A SHORT TO GROUND 

    Measure the resistance between the EGRTP sensor signal circuit pin C, harness side and ground

    Is the resistance greater than 10,000 ohms?

    Yes  No 
    INSTALL a new PCM REPAIR the circuit.
  6. AX7 PRELIMINARY DIAGNOSIS FOR DTC P0408 

    Possible causes:

    • signal circuit short to battery
    • signal return circuit open
    • EGRTP sensor
    • PCM

    Key off

    Disconnect the EGRTP sensor

    Key on, engine off

    Access the EGRTP_V PID

    Is the EGRTP_V PID voltage less than 0.3 volts?

    Yes  No 
    GO to AX8  GO to  AX9
  7. AX8 CHECK THE SIGNAL RETURN CIRCUIT FOR AN OPEN 

    Key off

    Disconnect the PCM engine harness connector

    Measure the resistance between the EGRTP sensor signal return circuit pin B, harness side and the PCM engine connector pin 25, harness side.

    Is the resistance less than 5 ohms?

    Yes  No 
    INSTALL a new EGRTP sensor REPAIR the circuit
  8. AX9 CHECK THE SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE 

    Key off

    Disconnect the PCM engine harness connector

    Key on, engine off

    Measure the voltage between the EGRTP sensor signal circuit pin C, harness side and ground

    Is any voltage indicated?

    Yes  No 
    REPAIR the circuit INSTALL a new PCM
  9. AX11 PRELIMINARY DIAGNOSIS FOR DTC P0487 
    NOTE: Additional DTCs may set during the utilization of output state control (OSC). Clear all PCM and TCM DTCs after diagnostics have been performed. Repeat the self-test to verify all DTCs have been cleared

    Possible causes:

    • EGRTP actuator circuits
    • EGRTP actuator
    • PCM

    Key off

    Disconnect the charge air cooler tube from the throttle body.

    Key on, engine off

    Access Output State Control

    Monitor the intake throttle plate

    Command the EGRTP actuator open and closed

    Does the throttle plate open and close?

    Yes  No 
    UNABLE to duplicate condition. CHECK for loose connections, damaged or corroded terminals or pins. REPAIR as necessary. REFER to ENGINE CONTROLS - SYMPTOM CHARTS -- 6.0L DIESEL if a driveability concern exists GO to AX12 
  10. AX12 CHECK THE PCM OUTPUT 
    NOTE: The PCM will activate the EGRTP actuator and perform a full sweep of the throttle plate for each key cycle with the IAT temperature greater than 0°C (32°F).

    Key off

    Disconnect the EGRTP actuator

    Measure the voltage between the EGRTP actuator circuit pin A, harness side and the EGRTP actuator circuit pin B, harness side.

    Monitor the EGRTP actuator and record the maximum and minimum voltage

    Key on, engine off

    Does the voltage cycle from 0 to 12 volts?

    Yes  No 
    INSTALL a new EGRTP actuator GO to AX13 
  11. AX13 CHECK THE EGRTP ACTUATOR CIRCUITS FOR AN OPEN 

    Key off

    Disconnect the PCM engine harness connector.

    Measure the resistance between the EGRTP actuator, harness side and the PCM engine connector, harness side as follows:

    • pin A and PCM pin 12
    • pin B and PCM pin 24

    Are the resistances less than 5 ohms?

    Yes  No 
    GO to AX14  REPAIR the circuit in question.
  12. AX14 CHECK THE EGRTP ACTUATOR CIRCUITS FOR A SHORT TO GROUND 

    Measure the resistance between the EGRTP actuator, harness side and ground as follows:

    • pin A
    • pin B

    Are the resistances greater than 10,000 ohms?

    Yes  No 
    GO to AX15  REPAIR the circuit in question.
  13. AX15 CHECK THE EGRTP ACTUATOR CIRCUITS FOR A SHORT TO VOLTAGE 

    Key on, engine off

    Measure the voltage between the EGRTP actuator, harness side and ground as follows:

    • pin A
    • pin B

    Is any voltage indicated?

    Yes  No 
    REPAIR the circuit in question. INSTALL a new PCM.
  14. AX16 PRELIMINARY DIAGNOSIS FOR DTC P0488 

    Possible causes:

    • throttle plate
    • EGRTP actuator
    • PCM

    Key off.

    Disconnect the charge air cooler tube from the throttle body.

    Visually inspect the throttle plate for binding or sticking.

    Does the throttle plate indicate any abnormal condition?

    Yes  No 
    INSTALL a new intake throttle assembly. GO to AX17 
  15. AX17 CHECK THE THROTTLE PLATE POSITIONS 
    NOTE: Additional DTCs may set during the utilization of output state control (OSC). Clear all PCM and TCM DTCs after diagnostics have been performed. Repeat the self-test to verify all DTCs have been cleared.

    Key on, engine off.

    Access Output State Control.

    Monitor the EGRTP_V PID and command the EGRTP actuator open and closed.

    Is the actuator voltage between 0.1 and 0.93 volts at 0 percent and does the actuator voltage steadily increase and decrease proportional to the commanded position?

    Yes  No 
    UNABLE to duplicate condition. CHECK for loose connections, damaged or corroded terminals or pins. REPAIR as necessary. REFER to ENGINE CONTROLS - SYMPTOM CHARTS -- 6.0L DIESEL if a driveability concern exists.. INSTALL a new intake throttle assembly.
  16. AX19 PRELIMINARY DIAGNOSIS FOR DTC P1334 
    NOTE: DTC P1334 is set when the EGRTP closed position voltage is less than 3.85 volts or when the EGRTP open position is greater than 0.93 volts at initial key on.

    Possible causes:

    • throttle plate
    • circuitry
    • EGRTP actuator
    • PCM

    Key off.

    Disconnect the charge air cooler tube from the throttle body.

    Visually inspect the throttle plate for binding or sticking.

    Does the throttle plate indicate any abnormal condition?

    Yes  No 
    INSTALL a new intake throttle assembly. GO to AX20 
  17. AX20 CHECK THE EGRTP SIGNAL VOLTAGE 
    NOTE: Additional DTCs may set during the utilization of output state control (OSC). Clear all PCM and TCM DTCs after diagnostics have been performed. Repeat the self-test to verify all DTCs have been cleared.

    Key on, engine off.

    Access Output State Control.

    Monitor the EGRTP_V PID

    Monitor the intake throttle plate.

    Command the intake throttle plate open and closed

    Is the intake throttle open position voltage less than 0.93 volts?

    Yes  No
    UNABLE to duplicate condition. CHECK for loose connections, damaged or corroded terminals or pins. REPAIR as necessary. REFER to ENGINE CONTROLS - SYMPTOM CHARTS -- 6.0L DIESEL if a driveability concern exists. GO to AX21 
  18. AX21 CHECK THE EGRTP ACTUATOR CIRCUITS FOR A SHORT TOGETHER 

    Key off.

    Disconnect the EGRTP actuator

    Disconnect the PCM engine harness connector.

    Measure the resistance between the EGRTP actuator pin A, harness side and the EGRTP actuator pin B, harness side.

    Is the resistance greater than 10,000 ohms?

    Yes  No 
    INSTALL a new intake throttle assembly. REPAIR the circuit.
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