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HOMESERVICE MANUALSMERCURY2009MILAN PREMIER, 3.0 1, AWDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 1930 (ENGINE CONTROLS - PINPOINT TESTS - (HYBRID) - FAULT CODE INDEX, PINPOINT TESTS A - DN)PINPOINT TEST DC: MASS AIR FLOW (MAF) SENSORTEST PROCEDURE
2009 Mercury Milan Premier, 3.0 1, AWD

Test Procedure

2009 Mercury Milan Premier, 3.0 1, AWDSECTION Test Procedure
WARNING: This page is about a different car, the 2006 Mercury Mariner and 2006 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
  1. DC1 DTCS P0102, P0103 AND P1101: CHECK FOR SELF-TEST DTCS 

    Are any of the following DTCs present during PCM or TCM self-test: P0102, P0103, or P1101? 

    Yes No
    For DTC P0102, GO to  DC3.
    For DTC P0103, GO to  DC19.
    For KOEO DTC P1101, GO to  DC7.
    For KOER DTC P1101, GO to  DC2.    		 GO to  DC25.
  2. DC2 DTC P1101: CHECK FOR MAF SENSOR CONTINUOUS MEMORY DTCS 
    • Retrieve any CMDTCs.

    Is a continuous memory MAF DTC present with the KOER DTC P1101? 

    Yes No
    GO to  DC3. Key in OFF position.
    GO to  DC5.
  3. DC3 VERIFY THE CONTINUOUS MEMORY DTC P0102 

    Is a continuous memory DTC P0102 present with the KOER DTC P1101? 

    Yes No
    GO to  DC5. GO to  DC4.
  4. DC4 VERIFY THE CONTINUOUS MEMORY DTC P0103 

    Is a continuous memory DTC P0103 present with the KOER DTC P1101? 

    Yes No
    GO to  DC19. All other continuous memory DTCs:
    DISREGARD the current diagnostic trouble code (DTC) at this time. DIAGNOSE the next DTC. GO to DIAGNOSTIC TROUBLE CODE (DTC) CHARTS AND DESCRIPTIONS .
  5. DC5 KOER AND CONTINUOUS MEMORY DTCS P0102 OR P1101: CHECK THE INTAKE AIR SYSTEM FOR LEAKS, OBSTRUCTIONS, AND DAMAGE 
    • Check the air inlet system (air cleaner, housing, ductwork) for obstructions or blockage.
    • Check for broken/loose air outlet tube clamps (throttle body and air cleaner assembly ends), cracks/holes in the air outlet tube, and worn gaskets between the MAF sensor and the air cleaner assembly. Verify the MAF sensor is connected. Repair as necessary.

    Are there any concerns found during the visual inspection? 

    Yes No
    Key in OFF position.
    REPAIR as necessary.    		 GO to  DC6.
  6. DC6 CHECK THE MAF PID 
    • Start the engine using the engine running diagnostic mode. Refer to DIAGNOSTIC MODES .
    • Run the engine up to 1,500 RPM for 5 seconds, then bring it back to idle.
    • Access the PCM and monitor the MAF V PID.

    Is the voltage less than 0.23 V? 

    Yes No
    Key in OFF position. Key in OFF position.
    GO to  DC9. GO to  DC7.
  7. DC7 CHECK THE MAF SIGNAL 
    NOTE: DTC P1101 can be generated by a low charged 12 volt battery or the garage exhaust ventilation system. Repair the 12 volt battery as necessary, then remove the ventilation system and properly vent to the outside atmosphere. Check the air inlet system (air cleaner, housing, ductwork) for obstructions or blockage. Repeat the KOEO self-test.
    • Key ON, engine OFF.
    • Access the PCM and monitor the MAF V PID.

    Is the voltage less than 0.2 V? 

    Yes No
    GO to  DC8. Key in OFF position.
    GO to  DC9.
  8. DC8 CHECK THE MAF SIGNAL SENT TO THE PCM 
    • Key ON, engine running.
    • Access the PCM and monitor the MAF V PID.

    Is the voltage between 0.46 V - 2.44 V? 

    Yes No
    Unable to identify the fault at this time. Key in OFF position.
    GO to Pinpoint Test Z . GO to  DC9.
  9. DC9 CHECK THE VPWR TO THE MAF SENSOR 
    • MAF/IAT Sensor connector disconnected.
    • Key ON, engine OFF.
    • Measure the voltage between:
      ( + ) MAF/IAT Sensor Connector, Harness Side ( - ) Vehicle Battery
      VPWR - Pin 6 Negative terminal

    Is the voltage greater than 10.5 V? 

    Yes No
    GO to  DC10. Key in OFF position. REPAIR the open circuit.
  10. DC10 CHECK THE PWRGND CIRCUIT TO THE MAF SENSOR 
    • Measure the voltage between:
      ( + ) Vehicle Battery ( - ) MAF/IAT Sensor Connector, Harness Side
      Positive terminal PWRGND - Pin 5

    Is the voltage greater than 10.5 V? 

    Yes No
    Key in OFF position.
    GO to  DC11.    		 Key in OFF position. REPAIR the open circuit.
  11. DC11 CHECK FOR SHORTS BETWEEN CIRCUITS IN THE MAF HARNESS 
    • PCM connector disconnected.
    • MAF Sensor connector disconnected.
    • Measure the resistance between:
      ( + ) MAF/IAT Sensor Connector, Harness Side ( - ) MAF/IAT Sensor Connector, Harness Side
      MAF - Pin 3 PWRGND - Pin 5
      MAF - Pin 3 MAF RTN - Pin 4
      MAF - Pin 3 SIGRTN - Pin 2
      MAF - Pin 3 IAT - Pin 1

    Are the resistances greater than 10K ohms? 

    Yes No
    GO to  DC12. REPAIR the short circuit.
  12. DC12 CHECK THE MAF RTN CIRCUIT FOR AN OPEN IN THE HARNESS 
    • Measure the resistance between:
      ( + ) PCM Connector, Harness Side ( - ) MAF/IAT Sensor Connector, Harness Side
      MAF RTN - Pin B43 MAF RTN - Pin 4

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  DC13. REPAIR the open circuit.
    CLEAR the DTCs. REPEAT the self-test.
  13. DC13 CHECK THE MAF RTN CIRCUIT FOR A SHORT TO PWRGND IN THE HARNESS 
    • Measure the resistance between:
      ( + ) MAF/IAT Sensor Connector, Harness Side ( - ) MAF/IAT Sensor Connector, Harness Side
      MAF RTN - Pin 4 PWRGND - Pin 5

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  DC14. REPAIR the short circuit to GND.
  14. DC14 CHECK THE MAF CIRCUIT FOR A SHORT TO PWRGND IN THE PCM 
    • PCM connector connected.
    • Measure the resistance between:
      ( + ) MAF/IAT Sensor Connector, Harness Side ( - ) MAF/IAT Sensor Connector, Harness Side
      MAF - Pin 3 PWRGND - Pin 5

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  DC15. GO to  DC29.
  15. DC15 CHECK THE MAF CIRCUIT VOLTAGE CYCLING INTEGRITY 
    • Key ON, engine OFF.
    • Access the MAF V PID.
    • Connect a 5 amp fused jumper wire between the following:
      MAF/IAT SENSOR CONNECTOR SPECIFICATION

      Point A MAF/IAT Sensor Connector, Harness Side Point B MAF/IAT Sensor Connector, Harness Side
      MAF RTN - Pin 4 PWRGND - Pin 5
      MAF - Pin 3 VPWR - Pin 6
    • Record the PID reading while both jumpers are installed.
    • Remove the VPWR jumper while monitoring the MAF V PID.

    Does the MAF V PID change from greater than 4.50 volts to less than 0.26 volt when the VPWR jumper is removed? 

    Yes No
    INSTALL a new MAF/IAT sensor.
    RESET the keep alive memory (KAM). REFER to RESETTING THE KEEP ALIVE MEMORY (KAM) .    		 GO to  DC16.
  16. DC16 CHECK THE MAF CIRCUIT FOR AN OPEN IN THE HARNESS 
    • Key in OFF position.
    • PCM connector disconnected.
    • Measure the resistance between:
      ( + ) PCM Connector, Harness Side ( - ) MAF/IAT Sensor Connector, Harness Side
      MAF - Pin B32 MAF - Pin 3

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  DC17. REPAIR the open circuit.
  17. DC17 CHECK THE PWRGND CIRCUIT FOR AN OPEN IN THE HARNESS 
    • Measure the resistance between:
      ( + ) MAF/IAT Sensor Connector, Harness Side ( - ) Vehicle Battery
      PWRGND - Pin 5 Negative terminal

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  DC18. REPAIR the open circuit.
  18. DC18 CHECK THE MAF RTN CIRCUIT FOR AN OPEN IN THE HARNESS 
    • Measure the resistance between:
      ( + ) PCM Connector, Harness Side ( - ) MAF/IAT Sensor Connector, Harness Side
      MAF RTN - Pin B43 MAF RTN - Pin 4

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  DC29. REPAIR the open circuit.
  19. DC19 DTC P0103: CHECK THE MAF SENSOR SCREEN FOR CONTAMINATION 
    NOTE: DTC P0103 can be generated by foreign material blocking the MAF sensor screen, causing an air flow restriction.
    • Check the MAF sensor screen for contamination or blockage.
    • Check the air cleaner element and air tubes for proper installation and sealing.

    Are any concerns present? 

    Yes No
    REPAIR as necessary.
    CLEAR the DTCs. REPEAT the self-test.    		 GO to  DC20.
  20. DC20 DTC P0103: CHECK THE MAF SENSOR SIGNAL HIGH INPUT TO THE PCM 
    • Key ON, engine OFF.
    • Access the PCM and monitor the MAF V PID.

    Is the voltage greater than 2.44 V? 

    Yes No
    GO to  DC21. GO to  DC23.
  21. DC21 CHECK THE MAF SENSOR SIGNAL SENT TO THE PCM 
    • Key in OFF position.
    • MAF/IAT Sensor connector disconnected.
    • Connect a 5 amp fused jumper wire between the following:
      Point A MAF/IAT Sensor Connector, Harness Side Point B MAF/IAT Sensor Connector, Harness Side
      MAF RTN - Pin 4 PWRGND - Pin 5
    • Key ON, engine OFF.
    • Access the PCM and monitor the MAF V PID.

    Is the voltage less than 0.1 V? 

    Yes No
    Key in OFF position.
    REMOVE the jumper wire(s)
    CHECK the MAF sensor electrical connector for damage, corrosion, and water intrusion.
    If OK, INSTALL a new MAF sensor.
    RESET the keep alive memory (KAM). REFER to RESETTING THE KEEP ALIVE MEMORY (KAM) .    		 GO to  DC22.
  22. DC22 CHECK THE MAF CIRCUIT FOR A SHORT TO POWER 
    • Key in OFF position.
    • PCM connector disconnected.
    • Key ON, engine OFF.
    • Measure the voltage between:
      ( + ) PCM Connector, Harness Side ( - )
      MAF - Pin B32 Ground

    Is the voltage less than 1 V? 

    Yes No
    GO to  DC24. Key in OFF position. REPAIR the short circuit to PWR.
  23. DC23 CHECK THE MAF SENSOR SIGNAL SENT TO THE PCM 
    • Start the engine using the engine running diagnostic mode. Refer to DIAGNOSTIC MODES .
    • Access the PCM and monitor the MAF V PID.
    • Monitor the MAF signal voltage while increasing the engine RPM from idle to approximately 2,500 RPM, then back to idle.

    Is the voltage between 0.23 - 4.6 V? 

    Yes No
    Key in OFF position.
    The concern is intermittent.
    GO to Pinpoint Test Z .    		 Key in OFF position.
    GO to  DC21.
  24. DC24 VERIFY THE IDLE CONCERN 
    • Start the engine using the engine running diagnostic mode. Refer to DIAGNOSTIC MODES .
    • PCM connector connected.
    • MAF/IAT sensor connector connected.

    Is there an idle concern present? 

    Yes No
    DISREGARD DTC P0103 at this time.
    The concern is elsewhere. RETURN to SYMPTOM CHARTS for further direction.    		 GO to  DC29.
  25. DC25 SYMPTOMS WITHOUT DTCS: CHECK THE CONDITIONS RELATED TO THE MAF SENSOR 
    • Check the air inlet system (air cleaner, housing, ductwork) for obstructions or blockage.
    • Check for broken/loose air outlet tube clamps (throttle body and air cleaner assembly ends), cracks/holes in the air outlet tube, and worn gaskets between the MAF sensor and the air cleaner assembly. Verify the MAF sensor is connected.

    Is a concern present? 

    Yes No
    REPAIR as necessary.
    RESET the keep alive memory (KAM). REFER to RESETTING THE KEEP ALIVE MEMORY (KAM) .    		 GO to  DC26.
  26. DC26 DTCS P0171, P0172, P2195 OR P2196: CHECK THE FUNCTIONALITY OF THE MAF SENSOR 
    NOTE: A MAF V PID value of less than 0.6 volt may indicate an incorrectly installed air cleaner or a leak in the air inlet system.
    • Start the engine using the engine running diagnostic mode. Refer to DIAGNOSTIC MODES .
    • Allow the engine to stabilize at the correct operating temperature.
    • Access the PCM and monitor the MAF V PID.
    • Check that the MAF V PID at idle and neutral is not greater than 30% of the normal MAF V listed in REFERENCE VALUES (or not greater than 2 volts).

    Is the PID value within the expected range? 

    Yes No
    GO to  DC28. GO to  DC27.
  27. DC27 CHECK TO ISOLATE THE MAF SENSOR FROM A LEAN DRIVEABILITY OCCURRENCE 
    NOTE: Due to increasingly stringent emission/OBD requirements, a fuel system DTC on some vehicles can be generated without a noticeable driveability concern with or without the MAF sensor disconnected. Under these conditions, if the MAF PID indicates a MAF sensor concern, install a new MAF sensor.
    • Key in OFF position.
    • MAF/IAT Sensor connector disconnected.
    • Key ON, engine running.
    • Drive the vehicle on the road.

    Is the lean driveability symptom (lack of power, spark knock/detonation, buck/jerk or hesitation/surge on acceleration) gone? 

    Yes No
    INSTALL a new MAF/IAT sensor.
    RESET the keep alive memory (KAM). REFER to RESETTING THE KEEP ALIVE MEMORY (KAM) .    		 GO to  DC28.
  28. DC28 VERIFY THE DTC 

    Are any of the following DTCs present: P0171, P0172, P2195, P2196? 

    Yes No
    Unable to duplicate or identify the fault at this time.
    GO to Pinpoint Test Z .    		 The concern is elsewhere. RETURN to SYMPTOM CHARTS for further direction.
  29. DC29 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 and 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) . The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
RENDER: 1.0x

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