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Test Procedure

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  1. J1 PRELIMINARY DIAGNOSIS FOR DIAGNOSTIC TROUBLE CODES (DTCS) P0101, P0103, P1102 
    • Carry out a visual inspection.
    • Retrieve and record all DTCs.
    • Clear all the DTCs.
    • Carry out the KOEO on-demand self-test.
    • Carry out the KOER on-demand self-test.

    Are DTCs P0101, P0103, or P1102 present? 

    Yes No
    For DTC P0101, GO to  J2.
    For DTC P1102, GO to  J4.
    For DTC P0103, GO to  J9.    		 UNABLE to duplicate the condition. CHECK for and air flow restriction. CHECK for a loose connection, and damaged or corroded terminals. WIGGLE the harness attempting to recreate the concern. REPAIR as necessary. REFER to SYMPTOM CHARTS , if a driveability concern exists.
  2. J2 DIAGNOSTIC TROUBLE CODE (DTC) P0101 
    NOTE: Visually inspect the vehicle for aftermarket accessories and performance modifications (exhaust system, turbocharger, performance chip). Refer to DIESEL ELECTRONIC ENGINE CONTROL (EEC) SYSTEM , Modifications to OBD Vehicles.
    • Possible causes:
      • MAF sensor
      • contaminated sensor
      • water intrusion
      • PCM
    • Check the MAF sensor for contamination.

    Is any restriction or contamination present? 

    Yes No
    REMOVE the restriction. REPAIR the system as necessary. CLEAR the DTCs. REPEAT the selftest. GO to  J3.
  3. J3 CHECK THE MAF OUTPUT SIGNAL TO THE PCM 
    • Key ON, engine OFF.
    • Access the PCM and monitor the MAF V PID.
    • Monitor the MAF PID at idle and record the value.
    • Increase the engine speed to approximately 2,500 RPM while monitoring the PID and record the value.

    Is the MAF PID value 1.2 to 1.8 volts with the engine at idle and 2.4 to 3.0 volts at 2,500 RPM? 

    Yes No
    GO to  J14. INSTALL a new MAF sensor. CLEAR the DTCs.
    REPEAT the self-test.
  4. J4 DIAGNOSTIC TROUBLE CODE (DTC) P1102 
    NOTE: Refer to the PCM connector pin numbers at the beginning of this pinpoint test.
    • Possible causes:
      • restricted air flow
      • unmetered air flow into engine
      • MAF sensor disconnected
      • VPWR circuit open to MAF
      • PWRGND circuit open to MAF
      • MAF RTN signal open
      • MAF sensor signal shorted to ground.
      • mechanical failure
      • MAF sensor
      • PCM
    • Inspect the air intake for restrictions.
    • Key in OFF position.
    • MAF/IAT Sensor connector disconnected.
    • Key ON, engine OFF.
    • Measure the voltage between:
      ( + ) MAF/IAT Sensor Connector, Harness Side ( - ) MAF/IAT Sensor Connector, Harness Side
      VPWR PWRGND

    Is the voltage greater than 10.5 V? 

    Yes No
    GO to  J5. REPAIR the open circuit. CLEAR the DTCs.
    REPEAT the self-test.
  5. J5 CHECK THE MAF RTN AND MAF PWRGND FOR AN OPEN 
    • Measure the voltage between:
      ( + ) MAF/IAT Sensor Connector, Harness Side ( - ) MAF/IAT Sensor Connector, Harness Side
      MAF RTN PWRGND

    Is the voltage between 5.5 - 6.5 V? 

    Yes No
    GO to  J6. REPAIR the open circuit. CLEAR the DTCs.
    REPEAT the self-test.
  6. J6 CHECK THE MAF SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND 
    • Key in OFF position.
    • PCM connector disconnected.
    • Measure the resistance between:
      ( + ) MAF/IAT Sensor Connector, Harness Side ( - )
      MAF Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  J7. REPAIR the short circuit. CLEAR the DTCs.
    REPEAT the self-test.
  7. J7 CHECK THE MAF SENSOR SIGNAL CIRCUIT FOR AN OPEN 
    • Measure the resistance between:
      ( + ) MAF/IAT Sensor Connector, Harness Side ( - ) PCM Connector, Harness Side
      MAF MAF - Pin B42

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  J8. REPAIR the open circuit. CLEAR the DTCs.
    REPEAT the self-test.
  8. J8 CHECK THE MAF SENSOR SIGNAL 
    NOTE: This step may cause DTC P0103 to set.
    • Key in OFF position.
    • PCM connector connected.
    • Key ON, engine OFF.
    • Access the PCM and monitor the MAF V PID.
    • Record the MAF V PID value.
    • 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 VPWR

    Does the MAF PID change from less than 0.04 volts to greater than 4.5 volts? 

    Yes No
    INSTALL a new MAF sensor. CLEAR the DTCs.
    REPEAT the self-test.    		 GO to  J14.
  9. J9 DIAGNOSTIC TROUBLE CODE (DTC) P0103 
    NOTE: Refer to the PCM and component connector pin numbers at the beginning of this pinpoint test.
    • Possible causes:
      • restricted inlet air flow
      • water intrusion
      • MAF signal circuit short to power
      • open ground circuit
      • MAF sensor
      • PCM
    • Disconnect the air inlet and check for restrictions and water intrusion.

    Is a concern present? 

    Yes No
    REPAIR as necessary. CLEAR the DTCs.
    REPEAT the self-test.    		 GO to  J10.
  10. J10 SIMULATE THE OPPOSITE SIGNAL 
    • Key in OFF position.
    • MAF/IAT Sensor connector disconnected.
    • The MAF/IAT sensor is disconnected to simulate the opposite DTC.
    • Key ON, engine OFF.
    • Carry out the KOER on-demand self-test.

    Is DTC P1102 present? 

    Yes No
    REASSEMBLE the vehicle. CLEAR the DTCs.
    REPEAT the self-test.
    GO to  J13.    		 GO to  J11.
  11. J11 CHECK THE MAF SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE 
    • Key in OFF position.
    • PCM connector disconnected.
    • Key ON, engine OFF.
    • Measure the voltage between:
      ( + ) MAF/IAT Sensor Connector, Harness Side ( - )
      MAF Ground

    Is the voltage less than 0.2 V? 

    Yes No
    GO to  J12. REPAIR the short to voltage.
    CLEAR the DTCs. REPEAT the self-test.
  12. J12 CHECK THE MAF RETURN CIRCUIT FOR AN OPEN 
    • Key in OFF position.
    • Measure the resistance between:
      ( + ) MAF/IAT Sensor Connector, Harness Side ( - ) PCM Connector, Harness Side
      MAF RTN MAF RTN - Pin B21

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  J14. REPAIR the open circuit. CLEAR the DTCs.
    REPEAT the self-test.
  13. J13 CHECK THE MAF SIGNAL TO THE PCM 
    • Access the PCM and monitor the MAF PID.
    • Key ON, engine running.
    • Monitor and record the MAF PID voltage value at idle.
    • Increase the engine speed to 2,500 RPM.
    • Record the MAF PID voltage value.

    Is the MAF PID value 1.2 to 1.8 volts with the engine at idle and 2.4 to 3.0 volts at 2,500 RPM? 

    Yes No
    UNABLE to duplicate the condition. CHECK for water intrusion. REFER to SYMPTOM CHARTS , if a driveability concern exists. INSTALL a new MAF sensor. CLEAR the DTCs.
    REPEAT the self-test.
  14. J14 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.
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