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Home >> Ford >> 2010 >> Escape Base, 2.5 7, AWD, Standard >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Pinpoint Test A: No Start Through Pinpoint Test DK: Accelerator Pedal Position (App) Sensor - (Except Diesel & Hybrid) >> Pinpoint Test DC: Mass Air Flow (MAF) Sensor >> Test Procedure
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Test Procedure

  1. DC1 CHECK FOR DIAGNOSTIC TROUBLE CODES (DTCS) 

    Are DTCs P0102, P0103, P0104, P1100, or P1101 present? 

    Yes No
    For KOER and continuous memory DTC P0102, GO to  DC5.
    For DTC P0103, GO to  DC21.
    For KOER and continuous memory DTC P0104, GO to  DC19.
    For KOEO DTC P1101, GO to  DC7.
    For KOER and continuous memory DTC P1101, GO to  DC2.
    For continuous memory DTC P1100, GO to  DC19.    		 For all other symptoms without DTCs, GO to  DC27.
  2. DC2 DTC P1101: CHECK FOR MAF SENSOR CONTINUOUS MEMORY DTCS 
    • Retrieve continuous memory DTCs.

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

    Yes No
    GO to  DC3. GO to  DC5.
  3. DC3 VERIFY 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 CONTINUOUS MEMORY DTC P0103 

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

    Yes No
    GO to  DC21. 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, P0104 OR P1101: CHECK THE INTAKE AIR SYSTEM FOR LEAKS, OBSTRUCTIONS, AND DAMAGE 
    • Ignition OFF.
    • Check the intake air 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. Check the throttle body bore for sludge. Verify the MAF sensor is connected. Repair as necessary.

    Are there any concerns found during the visual inspection? 

    Yes No
    REPAIR as necessary.
    CLEAR the DTCs. REPEAT the self-test.    		 GO to  DC6.
  6. DC6 CHECK THE MAF PID 
    • Access the PCM and monitor the RPM PID.
    • Run the engine up to 1,500 RPM for 5 seconds, then bring it back to idle.
    • Access the PCM and monitor the MAF PID.

    Is the voltage less than 0.23 V? 

    Yes No
    GO to  DC9. GO to  DC7.
  7. DC7 CHECK THE MAF SIGNAL SENT TO THE PCM 
    NOTE: DTC P1101 can be generated by a low charged vehicle battery or the garage exhaust ventilation system. Charge the battery as necessary, then remove the ventilation system and correctly vent to the outside atmosphere. Check the intake air system (air cleaner, housing, ductwork) for obstructions or blockage. Repeat the KOEO self-test.
    • Ignition OFF.
    • MAF/IAT Sensor connector connected.
    • Ignition ON, engine OFF.
    • Access the PCM and monitor the MAF PID.

    Is the voltage less than 0.2 V? 

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

    Is the voltage between 0.46 - 2.44 V? 

    Yes No
    Unable to identify the concern at this time.
    GO to PINPOINT TEST Z .    		 GO to  DC9.
  9. DC9 CHECK THE VPWR TO THE MAF SENSOR 
    • Ignition OFF.
    • MAF/IAT Sensor connector disconnected.
    • Ignition 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 V? 

    Yes No
    GO to  DC10. REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.
  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 V? 

    Yes No
    GO to  DC11. REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.
  11. DC11 CHECK FOR SHORTS BETWEEN THE CIRCUITS IN THE MAF HARNESS 
    • Ignition OFF.
    • MAF/IAT Sensor connector disconnected.
    • PCM 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. CLEAR the DTCs. REPEAT the self-test.
  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 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. CLEAR the DTCs. REPEAT the self-test.
  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  DC31.
  15. DC15 CHECK THE MAF CIRCUIT VOLTAGE CYCLING INTEGRITY 
    • Ignition ON, engine OFF.
    • Access the PCM and monitor the MAF PID.
    • 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
      MAF - Pin 3 VPWR - Pin 6
    • Record the PID reading while both jumpers are installed.
    • Remove the VPWR jumper while observing the MAF PID.

    Does the MAF PID change from greater than 4.50 volts to less than 0.20 volt when the VPWR jumper is removed? 

    Yes No
    INSTALL a new MAF/IAT sensor. REFER to the appropriate Electronic Engine Controls article . 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 
    • Ignition OFF.
    • Remove the jumper wire(s).
    • PCM connector disconnected.
    • Measure the resistance between:
      (+) PCM Connector, Harness Side (-) MAF/IAT Sensor Connector, Harness Side
      MAF MAF - Pin 3

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  DC17. REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.
  17. DC17 CHECK THE PWRGND CIRCUIT FOR AN OPEN IN THE HARNESS 
    • PCM connector disconnected.
    • 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. CLEAR the DTCs. REPEAT the self-test.
  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 MAF RTN - Pin 4

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  DC31. REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.
  19. DC19 DTC P1100: CHECK THE MAF CIRCUIT FOR INTERMITTENT VOLTAGE TO THE PCM 
    • 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.
    • Ignition ON, engine running.
    • Access the PCM and monitor the MAF PID.
    • If idle is not stable, refer to NO DIAGNOSTIC TROUBLE CODES (DTCS) PRESENT SYMPTOM CHART INDEX .
    • Run the engine up to 1,500 RPM for 5 seconds, then bring it back to idle. Run the engine up to 1,500 RPM for 5 seconds, then bring it back to idle.
    • Access the PCM and monitor the MAF PID.
    • Lightly tap on the MAF sensor and wiggle the harness connector to simulate road shock.

    Does the MAF PID go below 0.23 volt or above 4.6 volts? 

    Yes No
    INSPECT the MAF/IAT sensor connector. If OK, INSTALL a new MAF/IAT sensor. REFER to the appropriate Electronic Engine Controls article . RESET the keep alive memory (KAM). REFER to RESETTING THE KEEP ALIVE MEMORY (KAM) . GO to  DC20.
  20. DC20 CHECK THE MAF CIRCUIT FOR AN INTERMITTENT OPEN OR SHORTS 
    • Ignition ON, engine running.
    • Access the PCM and monitor the MAF PID.
    • Wiggle, shake, and bend small sections of the wiring harness while working from the sensor to the PCM.

    Does the MAF PID go below 0.23 volt or above 4.6 volts? 

    Yes No
    REPAIR as necessary. RESET the keep alive memory (KAM). REFER to RESETTING THE KEEP ALIVE MEMORY (KAM) . Unable to duplicate or identify the concern at this time. CLEAR the DTCs. REPEAT the self-test.
  21. DC21 DTC P0103: CHECK THE MAF SENSOR 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 correct installation and sealing.

    Are any concerns present? 

    Yes No
    REPAIR as necessary.
    CLEAR the DTCs. REPEAT the self-test.    		 GO to  DC22.
  22. DC22 DTC P0103: CHECK THE MAF SENSOR SIGNAL HIGH INPUT TO THE PCM 
    • Ignition ON, engine OFF.
    • Access the PCM and monitor the MAF PID.

    Is the voltage greater than 2.44 V? 

    Yes No
    GO to  DC23. GO to  DC25.
  23. DC23 CHECK THE MAF SENSOR SIGNAL SENT TO THE PCM 
    • Ignition OFF.
    • 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
    • Ignition ON, engine OFF.
    • Access the PCM and monitor the MAF PID.

    Is the voltage less than 0.1 V? 

    Yes No
    CHECK the MAF/IAT sensor electrical connector for damage, corrosion, and water ingress. If OK, INSTALL a new MAF/IAT sensor. REFER to the appropriate Electronic Engine Controls article . RESET the keep alive memory (KAM). REFER to RESETTING THE KEEP ALIVE MEMORY (KAM) . GO to  DC24.
  24. DC24 CHECK THE MAF CIRCUIT FOR A SHORT TO VOLTAGE 
    • Ignition OFF.
    • PCM connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) PCM Connector, Harness Side (-)
      MAF Ground

    Is the voltage less than 1 V? 

    Yes No
    GO to  DC26. REPAIR the short circuit to PWR. CLEAR the DTCs. REPEAT the self-test.
  25. DC25 CHECK THE MAF SIGNAL SENT TO THE PCM 
    • Ignition ON, engine running.
    • Access the PCM and monitor the RPM PID.
    • Monitor the MAF signal voltage while increasing the engine RPM from idle to approximately 2,500 RPM, and then back to idle.
    • Access the PCM and monitor the MAF PID.

    Is the voltage between 0.23 - 4.6 V? 

    Yes No
    This is an intermittent concern.
    GO to PINPOINT TEST Z .    		 GO to  DC23.
  26. DC26 VERIFY THE IDLE CONCERN 
    • PCM connector connected.
    • MAF/IAT Sensor connector connected.
    • Ignition ON, engine running.

    Is an idle concern present? 

    Yes No
    DISREGARD DTC P0103 at this time. The concern is elsewhere. RETURN to NO DIAGNOSTIC TROUBLE CODES (DTCS) PRESENT SYMPTOM CHART INDEX to DIAGNOSE unique idle concerns. GO to  DC31.
  27. DC27 SYMPTOMS WITHOUT DTCS: CHECK THE CONDITIONS RELATED TO THE MAF SENSOR 
    • Check the intake air 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  DC28.
  28. DC28 DTCS P0171, P0172, P0174, P0175, P2195, P2196, P2197 OR P2198: CHECK THE FUNCTIONALITY OF THE MAF SENSOR 
    NOTE: A MAF PID value of less than 0.35 volt may indicate an incorrectly installed air cleaner or a leak in the air inlet system.
    • Ignition ON, engine running.
    • Allow the engine to stabilize at the correct operating temperature.
    • Access the PCM and monitor the MAF PID.

    Is the MAF PID at idle and Neutral between 0.35 volt and 1.3 volts? 

    Yes No
    GO to  DC30. GO to  DC29.
  29. DC29 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. Refer to the appropriate Electronic Engine Controls article .
    • Ignition OFF.
    • MAF/IAT Sensor connector disconnected.
    • Ignition 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. REFER to the appropriate Electronic Engine Controls article . RESET the keep alive memory (KAM). REFER to RESETTING THE KEEP ALIVE MEMORY (KAM) . GO to  DC30.
  30. DC30 VERIFY THE DTC 

    Are any of the following DTCs present: 

    P0171, P0172, P0174, P0175, P2195, P2196, P2197, or P2198? 

    Yes No
    Unable to duplicate or identify the concern at this time.
    GO to PINPOINT TEST Z .    		 The concern is elsewhere.
    RETURN to NO DIAGNOSTIC TROUBLE CODES (DTCS) PRESENT SYMPTOM CHART INDEX , to DIAGNOSE performance while driving concerns.
  31. DC31 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) , 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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