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Home >> Ford >> 2021 >> F-150 Raptor >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Pinpoint Tests (Diesel) >> Pinpoint Tests A: No Start >> Test Procedure
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Test Procedure

  1. A1 VERIFY THE ENGINE STARTS 

    Does the engine start? 

    Yes No
    GO to  A6. GO to  A2.
  2. A2 CHECK THE VREF CIRCUIT FOR VOLTAGE 
    • Ignition OFF.
    • For Transit Connect,
    • MAP/CACT Sensor connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) MAP/CACT Sensor Connector, Harness Side (-)
      VREF - Pin 2 Ground
    • For all others,
    • MAP Sensor connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) MAP Sensor Connector, Harness Side (-)
      VREF - Pin 3 Ground

    Is the voltage between 4.5 - 5.5 V? 

    Yes No
    GO to  A3. GO to PINPOINT TEST B .
  3. A3 CHECK FOR VREF VOLTAGE AT THE SENSOR 
    • Ignition OFF.
    • MAP Sensor connector connected.
    • MAP/CACT Sensor connector connected.
    • FRP Sensor connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
    (+) FRP Sensor Connector, Harness Side (-)
    VREF Ground

    Is the voltage between 4.5 - 5.5 V? 

    Yes No
    GO to  A4. GO to PINPOINT TEST B .
  4. A4 CHECK THE RPM 
    • Ignition OFF.
    • FRP Sensor connector connected.
    • Access the PCM and monitor the RPM (RPM) PID.
    • Crank the engine while monitoring the PID.

    Is the RPM greater than 150 RPM? 

    Yes No
    GO to  A5. GO to PINPOINT TEST D .
  5. A5 CHECK THE CMP SENSOR 
    • Access the PCM and monitor the CMP_F (MODE) PID.
    • Crank the engine while monitoring the PID.

    Is a concern present? 

    Yes No
    GO to PINPOINT TEST V . GO to  A7.
  6. A6 CHECK THE VPWR VOLTAGE 
    NOTE: An open VPWR circuit concern is indicated by a VPWR PID value greater than 15 V while the engine is running.
    • Ignition ON, engine running.
    • Access the PCM and monitor the VPWR (VOLT) PID.

    Is the voltage less than 15 V? 

    Yes No
    GO to  A7. REPAIR the open VPWR circuit.
    Clear the PCM DTCs. REPEAT the self-test.
  7. A7 CHECK THE FUEL 
    • Check for sufficient clean fuel. Refer to DIAGNOSTIC PROCEDURES and carry out the Sufficient Clean Fuel Test.

    Is a concern present? 

    Yes No
    REPAIR as necessary.
    Clear the PCM DTCs. REPEAT the self-test.    		 GO to  A8.
  8. A8 CHECK THE LOW PRESSURE FUEL SYSTEM 
    NOTE: On some vehicles, the FP PID may not turn off the fuel pump. Cycle the ignition from ON to OFF to command the fuel pump OFF.
    • Ignition ON, engine OFF.
    • Access the PCM and monitor the FLP (PRESS) PID.
    • Access the PCM and control the FP (MODE) PID.
    • Command the fuel pump ON.

    Is the low pressure fuel system pressure greater than 414 kPa (61 psi) (F-150) or greater than 379 kPa (55 psi) (all others)? 

    Yes No
    GO to  A9. GO to PINPOINT TEST MA .
  9. A9 CHECK THE FUEL PRESSURE 
    • Access the PCM and monitor the FRP (PRESS) PID.
    • Crank the engine while monitoring the PID.

    Is the pressure greater than 14000 kPa (2030.53 psi)? 

    Yes No
    GO to  A10. GO to PINPOINT TEST M .
  10. A10 CARRY OUT A RELATIVE COMPRESSION TEST 
    • Carry out the Relative Compression test on the scan tool.

    Is a concern present? 

    Yes No
    REFER to the appropriate Engine, Diagnosis and Testing, Engine article to DIAGNOSE a base engine concern. RETURN to SYMPTOM CHARTS for further direction.
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