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Home >> Ford >> 2014 >> Expedition XL, 4WD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Pinpoint Test H: Fuel Control Through Pinpoint Test JD: Crankshaft Position (CKP) Sensor - (Except Diesel & Hybrid) >> PINPOINT TEST HH: Exhaust Gas Recirculation System Module (ESM) >> Test Procedure
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Test Procedure

  1. HH1 CHECK FOR DTCS 

    Are DTCs P0401, P0402, P0403, P0405, P0406, P1408, or P1409 present? 

    Yes No
    For DTC P0401, GO to  HH16.
    For DTC P0402, GO to  HH12.
    For DTC P0405, GO to HH2  .
    For DTC P0406, GO to  HH5.
    For DTC P1408, GO to  HH17.
    For all others, GO to  HH22.    		 For symptoms without DTCs, GO to  HH28.
    For all others, RETURN to NO DIAGNOSTIC TROUBLE CODES (DTCS) PRESENT SYMPTOM CHART INDEX for further direction.
  2. HH2 DTC P0405: DETERMINE THE PRESENT DPFEGR PID VOLTAGE 
    • Ignition ON, engine OFF.
    • Access the PCM and monitor the DPFEGR (VOLT) PID.

    Is the voltage less than 0.05 V? 

    Yes No
    GO to HH3  . GO to  HH11.
  3. HH3 INDUCE THE OPPOSITE DIFFERENTIAL PRESSURE FEEDBACK EGR SENSOR SIGNAL 
    • Ignition OFF.
    • ESM connector disconnected.
    • Ignition ON, engine OFF.
    • Access the PCM and monitor the DPFEGR (VOLT) PID.

    Is the voltage between 4 - 6 V? 

    Yes No
    INSTALL a new Differential Pressure Feedback EGR sensor. REFER to the applicable service information article, Engine Emission Control.
    Clear the PCM DTCs. REPEAT the self-test.    		 GO to HH4  .
  4. HH4 CHECK THE DPFE CIRCUIT FOR A SHORT TO SIGRTN OR GND 
    • Ignition OFF.
    • PCM connector disconnected.
    • Measure the resistance between:
      (+) PCM Connector, Harness Side (-) PCM Connector, Harness Side
      DPFE SIGRTN
    • Measure the resistance between:
      (+) PCM Connector, Harness Side (-) Vehicle Battery
      DPFE Negative terminal

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  HH29. REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test.
  5. HH5 DTC P0406: DETERMINE THE PRESENT DPFEGR PID VOLTAGE 
    • Ignition ON, engine OFF.
    • Access the PCM and monitor the DPFEGR (VOLT) PID.

    Is the voltage greater than 4 V? 

    Yes No
    GO to HH6  . GO to  HH11.
  6. HH6 CHECK THE VREF VOLTAGE TO THE ESM 
    • Ignition OFF.
    • ESM connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) ESM Connector, Harness Side (-) Vehicle Battery
      VREF - Pin 2 Negative terminal

    Is the voltage between 4 - 5.5 V? 

    Yes No
    GO to HH7  . REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test.
  7. HH7 CHECK THE DPFE CIRCUIT FOR A SHORT TO VOLTAGE 
    • Ignition OFF.
    • PCM connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) ESM Connector, Harness Side (-) Vehicle Battery
      DPFE - Pin 5 Negative terminal

    Is any voltage present? 

    Yes No
    REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test. GO to HH8  .
  8. HH8 CHECK THE DPFE CIRCUIT FOR A SHORT TO VREF 
    • Ignition OFF.
    • Measure the resistance between:
      (+) PCM Connector, Harness Side (-) PCM Connector, Harness Side
      VREF DPFE

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to HH9  . REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test.
  9. HH9 CHECK THE DPFE AND SIGRTN CIRCUITS FOR AN OPEN 
    • Measure the resistance between:
      (+) PCM Connector, Harness Side (-) ESM Connector, Harness Side
      DPFE DPFE - Pin 5
      SIGRTN SIGRTN - Pin 6

    Are the resistances less than 5 ohms? 

    Yes No
    GO to HH10  . REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test.
  10. HH10 INDUCE THE OPPOSITE DIFFERENTIAL PRESSURE FEEDBACK EGR SENSOR VOLTAGE 
    • PCM connector connected.
    • Connect a 5 amp fused jumper wire between the following:
      Point A ESM Connector, Harness Side Point B ESM Connector, Harness Side
      DPFE - Pin 5 SIGRTN
    • Ignition ON, engine OFF.
    • Access the PCM and monitor the DPFEGR (VOLT) PID.

    Is the voltage less than 0.1 V? 

    Yes No
    INSTALL a new Differential Pressure Feedback EGR sensor. REFER to the applicable service information article, Engine Emission Control.
    Clear the PCM DTCs. REPEAT the self-test.    		 GO to  HH29.
  11. HH11 CARRY OUT A THOROUGH WIGGLE TEST ON THE ESM HARNESS 
    • Access the PCM and monitor the DPFEGR (VOLT) PID.
    • Wiggle, shake, and bend small sections of the wiring harness while working from the sensor to the PCM.

    Is there any change in the voltage reading, or is a concern found? 

    Yes No
    REPAIR as necessary.
    Clear the PCM DTCs. REPEAT the self-test.    		 Unable to duplicate or identify the concern at this time.
    GO to PINPOINT TEST Z .
  12. HH12 DTC P0402: CHECK THE VREF VOLTAGE TO THE ESM 
    NOTE: Diagnose and repair all circuit concern DTCs before diagnosing range/performance or flow concerns. For circuit concern DTC diagnosis, refer to DIAGNOSTIC TROUBLE CODE (DTC) CHARTS AND DESCRIPTIONS .
    • Ignition OFF.
    • ESM connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) ESM Connector, Harness Side (-) Vehicle Battery
      VREF - Pin 2 Negative terminal

    Is the voltage between 4.5 - 5.5 V? 

    Yes No
    GO to HH13  . GO to PINPOINT TEST C .
  13. HH13 SIMULATE THE DIFFERENTIAL PRESSURE FEEDBACK EGR SENSOR SIGNAL WITH A VACUUM PUMP 
    • Disconnect the downstream differential pressure feedback EGR sensor port hose at the ESM.
    • Verify the hose and port are clear and free of obstructions.
    • Connect a vacuum pump to the downstream differential pressure feedback EGR sensor port.
    • Ignition ON, engine OFF.
    • Access the PCM and monitor the DPFEGR (VOLT) PID.
    • Apply 27 - 30 kPa (8 - 9 in-Hg) vacuum to the differential pressure feedback EGR sensor and hold for 10 seconds.
    • Quickly release the vacuum.
      • The DPFEGR PID voltage must be between 0.25 and 1.3 volts with the ignition ON and no vacuum applied.
      • The DPFEGR PID voltage must increase to greater than 4 volts with the vacuum applied.
      • The DPFEGR PID must drop to less than 1.5 volts in less than 3 seconds when the vacuum is released.

    Does the DPFEGR PID voltage indicate a concern in the differential pressure feedback EGR sensor? 

    Yes No
    INSTALL a new Differential Pressure Feedback EGR sensor. REFER to the applicable service information article, Engine Emission Control.
    Clear the PCM DTCs. REPEAT the self-test.    		 GO to HH14  .
  14. HH14 INSPECT THE EGR VACUUM REGULATOR SOLENOID VENT FOR BLOCKAGE 
    NOTE: When the EGR valve is closed, the EGR vacuum regulator solenoid vacuum is vented through the solenoid vent to the atmosphere. A plugged EGR vacuum regulator solenoid vent does not allow EGR vacuum to vent to the atmosphere.
    • EGR vacuum regulator vacuum hoses disconnected.
    • Connect a hand vacuum pump to the EGR vacuum regulator source port.
    • Apply 34 to 51 kPa (10 to 15 in-Hg) vacuum.

    Does the EGR vacuum regulator solenoid vacuum bleed off? 

    Yes No
    GO to HH15  . INSTALL a new EGR vacuum regulator solenoid.
    REFER to the applicable service information article, Engine Emission Control.
    Clear the PCM DTCs. REPEAT the self-test.
  15. HH15 CHECK THE EGR VALVE FOR CARBON BUILD-UP 
    • Remove the ESM.
    • Visually inspect the EGR valve and valve seat for correct seating, carbon build-up and debris.

    Is a concern present? 

    Yes No
    REPAIR as necessary.
    Clear the PCM DTCs. REPEAT the self-test.    		 Unable to duplicate or identify the concern at this time.
  16. HH16 CARRY OUT THE KOER SELF-TEST 
    NOTE: Diagnose and repair all circuit concern DTCs before diagnosing range/performance or flow concerns.
    • Carry out the KOER self-test.

    Is DTC P1408 present? 

    Yes No
    GO to HH17  . GO to  HH18.
  17. HH17 CHECK THE VREF VOLTAGE TO THE ESM 
    • Ignition OFF.
    • ESM connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) ESM Connector, Harness Side (-) Vehicle Battery
      VREF - Pin 2 Negative terminal

    Is the voltage between 4.5 - 5.5 V? 

    Yes No
    GO to HH18  . GO to PINPOINT TEST C .
  18. HH18 CHECK THE EGR VACUUM REGULATOR SOLENOID VACUUM 
    • ESM connector connected.
    • Disconnect the EGR vacuum regulator vacuum source hose.
    • Connect a vacuum gauge to the EGR vacuum regulator vacuum source hose.
    • Ignition ON, engine running.
    • Monitor the vacuum gauge.

    Is the manifold vacuum greater than 34 kPa (10 in-Hg)? 

    Yes No
    GO to HH19  . REPAIR as necessary.
    Clear the PCM DTCs. REPEAT the self-test.
  19. HH19 SIMULATE THE DIFFERENTIAL PRESSURE FEEDBACK EGR SENSOR SIGNAL WITH A VACUUM PUMP 
    • Ignition OFF.
    • Disconnect the downstream differential pressure feedback EGR sensor port hose at the ESM.
    • Verify the hose and port are clear and free of obstructions.
    • Connect a vacuum pump to the downstream differential pressure feedback EGR sensor port.
    • Ignition ON, engine OFF.
    • Access the PCM and monitor the DPFEGR (VOLT) PID.
    • Apply 27 - 30 kPa (8 - 9 in-Hg) vacuum to the differential pressure feedback EGR sensor and hold for 10 seconds.
    • Quickly release the vacuum.
      • The DPFEGR PID voltage must be between 0.25 and 1.3 volts with the ignition ON and no vacuum applied.
      • The DPFEGR PID voltage must increase to greater than 4 volts with the vacuum applied.
      • The DPFEGR PID must drop to less than 1.5 volts in less than 3 seconds when the vacuum is released.

    Does the DPFEGR PID voltage indicate a concern in the differential pressure feedback EGR sensor? 

    Yes No
    INSTALL a new Differential Pressure Feedback EGR sensor. REFER to the applicable service information article, Engine Emission Control.
    Clear the PCM DTCs. REPEAT the self-test.    		 CONNECT all the hoses.
    GO to HH20  .
  20. HH20 CHECK THE EGR VACUUM REGULATOR SOLENOID OPERATION 
    • Ignition ON, engine running.
    • Engine at normal operating temperature.
    • Allow the engine idle to stabilize.
    • Access the PCM and monitor the RPM (RPM) PID.
    • Access the PCM and control the EGRPCT (PER) PID.
    • Increase the EGR vacuum regulator duty cycle while monitoring the RPM PID.

    Does the RPM decrease or the engine stall as the EGR vacuum regulator duty cycle is increased? 

    Yes No
    Unable to duplicate or identify the concern at this time. GO to HH21  .
  21. HH21 CHECK FOR THE PRESENCE OF CARBON BUILD-UP IN THE EGR PASSAGE 
    NOTE: In certain vehicle applications, carbon build-up may occur downstream of the ESM. An inspection is required to make sure the passage in the upper intake manifold plenum chamber behind the ESM is open to allow exhaust gas flow.
    • Ignition OFF.
    • Remove the ESM. Refer to the applicable service information article, Engine Emission Control.
    • Disconnect the air inlet tube from the throttle body.
    • Prop open the throttle body.
    • Apply regulated shop air to the EGR port at the location where the ESM attaches to the upper intake manifold.

    Is a restriction concern present? 

    Yes No
    CLEAN the EGR port as necessary and INSTALL the ESM.
    REFER to the applicable service information article, Engine Emission Control.
    Clear the PCM DTCs. REPEAT the self-test.    		 INSTALL a new ESM.
    REFER to the applicable service information article, Engine Emission Control.
    Clear the PCM DTCs. REPEAT the self-test.
  22. HH22 CHECK THE EGR VACUUM REGULATOR SOLENOID OPERATION 
    • Ignition ON, engine running.
    • Engine at normal operating temperature.
    • Allow the engine idle to stabilize.
    • Access the PCM and monitor the RPM (RPM) PID.
    • Access the PCM and control the EGRPCT (PER) PID.
    • Increase the EGR vacuum regulator duty cycle while monitoring the RPM PID.

    Does the RPM decrease or the engine stall as the EGR vacuum regulator duty cycle is increased? 

    Yes No
    Unable to duplicate or identify the concern at this time.
    GO to PINPOINT TEST Z .    		 GO to HH23  .
  23. HH23 CHECK THE VPWR VOLTAGE TO THE EGR VACUUM REGULATOR SOLENOID 
    • Ignition OFF.
    • ESM connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) ESM Connector, Harness Side (-) Vehicle Battery
      VPWR - Pin 4 Negative terminal

    Is the voltage greater than 10.5 V? 

    Yes No
    GO to HH24  . REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test.
  24. HH24 CHECK THE EGR VACUUM REGULATOR SOLENOID COIL RESISTANCE 
    • Ignition OFF.
    • Measure the resistance between:
      (+) ESM Connector, Component Side (-) ESM Connector, Component Side
      VPWR - Pin 4 EVR - Pin 1

    Is the resistance between 26 - 40 ohms? 

    Yes No
    GO to HH25  . INSTALL a new EGR Vacuum Regulator solenoid.
    REFER to the applicable service information article, Engine Emission Control.
    Clear the PCM DTCs. REPEAT the self-test.
  25. HH25 CHECK THE EVR CIRCUIT FOR AN OPEN 
    • PCM connector disconnected.
    • Measure the resistance between:
      (+) ESM Connector, Harness Side (-) PCM Connector, Harness Side
      EVR - Pin 1 EVR

    Is the resistance less than 5 ohms? 

    Yes No
    GO to HH26  . REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test.
  26. HH26 CHECK THE EVR CIRCUIT FOR A SHORT TO VOLTAGE 
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) PCM Connector, Harness Side (-) Vehicle Battery
      EVR Negative terminal

    Is any voltage present? 

    Yes No
    REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test. GO to HH27  .
  27. HH27 CHECK THE EVR CIRCUIT FOR A SHORT TO GND 
    • Ignition OFF.
    • Measure the resistance between:
      (+) PCM Connector, Harness Side (-)
      EVR Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  HH29. REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test.
  28. HH28 EGR DIAGNOSIS BY SYMPTOM: CHECK FOR EGR FLOW WITH THE EGR VACUUM REGULATOR VACUUM HOSE DISCONNECTED AND PLUGGED 
    NOTE: An increase in DPFEGR PID voltage at idle indicates EGR flow.
    • Carry out the KOER self-test. Repair any other DTCs.
    • Possible causes for EGR flow at idle with no related DTCs:
      • EGR valve not fully seating
      • EGR vacuum regulator solenoid vent restricted
      • damaged EGR vacuum regulator solenoid
    • Disconnect and plug the EGR vacuum regulator vacuum source hose.
    • Ignition ON, engine OFF.
    • Access the PCM and monitor the DPFEGR (VOLT) PID.
    • Record the PID voltage.
    • Ignition ON, engine running.
    • With the engine at idle, observe the DPFEGR PID voltage. Compare to engine OFF voltage.

    Is the idle DPFEGR PID voltage greater than 0.15 V when compared to the KOEO DPFEGR PID voltage? 

    Yes No
    REMOVE and INSPECT the ESM for signs of contamination, unusual wear, carbon deposits, binding or other damage.
    REPAIR as necessary.
    If no concerns are present, INSTALL a new ESM.
    REFER to the applicable service information article, Engine Emission Control.
    Clear the PCM DTCs. REPEAT the self-test.    		 INSPECT the EGR vacuum regulator solenoid vent for blockage.
    To continue symptom diagnosis, REFER to NO DIAGNOSTIC TROUBLE CODES (DTCS) PRESENT SYMPTOM CHARTS .
  29. HH29 CHECK FOR CORRECT PCM OPERATION 
    • Disconnect all the PCM connectors.
    • Visually inspect for:
      • pushed out pins
      • corrosion
    • Connect all the PCM connectors and make sure they seat correctly.
    • Carry out the PCM self-test.
    • Verify the concern is still present.

    Is the concern still present? 

    Yes No
    INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) , Programming the VID Block for a Replacement PCM. The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
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