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Home >> Ford >> 2015 >> Transit-150 Base, 3.2L Eng VIN V >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Pinpoint Tests (Diesel) >> Pinpoint Test AF: Glow Plug System >> Test Procedure
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Test Procedure

  1. AF1 PRELIMINARY DIAGNOSIS 
    • Clear the PCM DTCs.
    • Carry out the KOER Glow Plug Monitor self-test.

    Are any DTCs present? 

    Yes No
    For DTCs U0074 or U0106, GO to  AF10.
    For all others, GO to AF2  .    		 For symptoms without DTCs, GO to AF2  .
    For all others, RETURN to SYMPTOM CHARTS for further direction.
  2. AF2 REPROGRAM THE GPCM OR UPDATE THE GPCM CALIBRATION 
    NOTE: Wait for 2 minutes before disconnecting any GPCM connectors.
    • Disconnect all the GPCM connectors.
    • Visually inspect for:
      • pushed out pins
      • corrosion
      • damaged seals
    • Connect all the GPCM connectors and make sure they seat correctly.
    • Clear the PCM DTCs.
    • Carry out the KOER Glow Plug Monitor self-test.
    • If any glow plug DTCs are retrieved again, turn the ignition OFF and wait for 2 minutes.
    • Reprogram the GPCM or update the GPCM calibration.
    • Clear the PCM DTCs.
    • Carry out the KOER Glow Plug Monitor self-test.

    Are any glow plug DTCs retrieved again? 

    Yes No
    GO to AF3  . The system is operating correctly at this time.
    The concern may have been caused by a loose or corroded connector.
  3. AF3 CHECK THE SUSPECT GLOW PLUG RESISTANCE 
    NOTE: Use the component connector information to match the connector pins with the DTCs.
    • Ignition OFF.
    • Glow Plug connector disconnected.
    • Check for loose, damaged, or backed out terminals.
    • Measure the resistance between:
      (+) Glow Plug Connector, Component Side (-)
      Suspect Glow Plug Ground

    Is the resistance less than 2 ohms? 

    Yes No
    GO to AF4  . INSTALL a new Glow Plug. REFER to the service information , Glow Plug System.
    Carry out the KOER Glow Plug Monitor self-test.
    Clear the PCM DTCs. REPEAT the self-test.
  4. AF4 CHECK THE VBATT CIRCUIT FOR VOLTAGE 
    NOTE: Wait for 2 minutes before disconnecting any GPCM connectors.
    • GPCM-A connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) GPCM-A Connector, Harness Side (-)
      VBATT - Pin 1 Ground

    Is the voltage greater than 10.5 V? 

    Yes No
    GO to AF5  . REPAIR the open circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  5. AF5 CHECK THE GLOW PLUG CIRCUIT FOR AN OPEN 
    NOTE: Wait for 2 minutes before disconnecting any GPCM connectors.
    • Ignition OFF.
    • GPCM-B connector disconnected.
    • Measure the resistance between:
      (+) GPCM-B Connector, Harness Side (-) Glow Plug Connector, Harness Side
      Suspect Glow Plug Suspect Glow Plug

    Is the resistance less than 5 ohms? 

    Yes No
    GO to AF6  . REPAIR the open circuit.
    Carry out the KOER Glow Plug Monitor self-test.
    Clear the PCM DTCs. REPEAT the self-test.
  6. AF6 CHECK THE GLOW PLUG CIRCUIT FOR A SHORT TO GROUND 
    • Measure the resistance between:
      (+) Glow Plug Connector, Harness Side (-)
      Suspect Glow Plug Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to AF7  . REPAIR the short circuit.
    Carry out the KOER Glow Plug Monitor self-test.
    Clear the PCM DTCs. REPEAT the self-test.
  7. AF7 CHECK THE GLOW PLUG CIRCUIT FOR A SHORT TO VOLTAGE 
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) Glow Plug Connector, Harness Side (-)
      Suspect Glow Plug Ground

    Is any voltage present? 

    Yes No
    REPAIR the short circuit.
    Carry out the KOER Glow Plug Monitor self-test.
    Clear the PCM DTCs. REPEAT the self-test.    		 GO to AF8  .
  8. AF8 CHECK THE VPWR CIRCUIT FOR VOLTAGE 
    NOTE: Wait for 2 minutes before disconnecting any GPCM connectors.
    • Ignition OFF.
    • GPCM-C connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) GPCM-C Connector, Harness Side (-)
      VPWR - Pin 6 Ground

    Is the voltage greater than 10.5 V? 

    Yes No
    GO to AF9  . REPAIR the open circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  9. AF9 CHECK THE PWRGND CIRCUIT FOR AN OPEN 
    • Measure the resistance between:
      (+) GPCM-C Connector, Harness Side (-)
      PWRGND - Pin 5 Ground

    Is the resistance less than 5 ohms? 

    Yes No
    For DTC P138B, GO to  AF13.
    For all others, GO to AF10  .    		 REPAIR the open circuit. CLEAR the DTCs.
    REPEAT the self-test.
  10. AF10 CHECK THE CAN2 CIRCUITS FOR AN OPEN 
    • Ignition OFF.
    • PCM-B connector disconnected.
    • Measure the resistance between:
      (+) GPCM-C Connector, Harness Side (-) PCM-B Connector, Harness Side
      CAN2+ - Pin 3 CAN2+ - Pin 56
      CAN2- - Pin 4 CAN2- - Pin 39

    Are the resistances less than 5 ohms? 

    Yes No
    GO to AF11  . REPAIR the open circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  11. AF11 CHECK THE CAN2 CIRCUITS FOR A SHORT TO GROUND 
    • Measure the resistance between:
      (+) GPCM-C Connector, Harness Side (-)
      CAN2+ - Pin 3 Ground
      CAN2- - Pin 4 Ground

    Are the resistances greater than 10K ohms? 

    Yes No
    GO to AF12  . REPAIR the short circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  12. AF12 CHECK THE CAN2 CIRCUITS FOR A SHORT TO VOLTAGE 
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) GPCM-C Connector, Harness Side (-)
      CAN2+ - Pin 3 Ground
      CAN2- - Pin 4 Ground

    Is any voltage present? 

    Yes No
    REPAIR the short circuit. Clear the PCM DTCs.
    REPEAT the self-test.    		 GO to AF13  .
  13. AF13 CHECK FOR CORRECT GPCM OPERATION 
    NOTE: Wait for 2 minutes before disconnecting any GPCM connectors.
    • Disconnect all the GPCM connectors.
    • Visually inspect for:
      • pushed out pins
      • corrosion
    • Connect all the GPCM connectors and make sure they seat correctly.
    • Carry out the GPCM self-test and verify the concern is still present.

    Is the concern still present? 

    Yes No
    INSTALL a new GPCM. REFER to the service information , Glow Plug System.
    CLEAR the DTCs. REPEAT the self-test.    		 The system is operating correctly at this time.
    The concern may have been caused by a loose or corroded connector.
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