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Home >> Ford >> 2012 >> Explorer Base, 3.5 8, FWD, 6F55 >> Repair and Diagnosis (Single Page) >> Engine Performance >> Testing & Diagnosis >> Engine Controls - Pinpoint Test A: No Start Through Pinpoint Test Dm: Manifold Absolute Pressure (Map) Sensor - (Except Diesel & Hybrid) >> PINPOINT TEST B: Powertrain Control Module (PCM) Power Relay >> Test Procedure
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Test Procedure

  1. B1 CHECK FOR DIAGNOSTIC TROUBLE CODES (DTCS) 

    Are DTCs P0685, P0686, P0687, P0689, P068A, P0690, P1793, P2510, or U300C present? 

    Yes No
    For DTC P068A, GO to  B2.
    For DTC P0689 and P2510, GO to  B13.
    For all others, GO to  B9.    		 GO to  B4.
  2. B2 CHECK THE BATTERY AND CHARGING SYSTEM 
    • Check the battery and charging system voltages. Refer to the appropriate Charging System article, Inspection and Verification.

    Are the battery and charging system voltages within specification? 

    Yes No
    GO to  B3. REPAIR as necessary. REFER to the appropriate Charging System article, Symptom Chart to diagnose the system voltage low or battery is discharged symptom or the system voltage high symptom.
    Clear the PCM DTCs. REPEAT the self-test.
  3. B3 CHECK THE PCM POWER RELAY 
    • Carry out the PCM power relay component test. Refer to the appropriate ELECTRONIC CONTROLS - COMPONENT TESTING article .

    Does the PCM power relay pass the component test? 

    Yes No
    GO to  B4. INSTALL a new PCM Power Relay. Clear the PCM DTCs. REPEAT the self-test.
  4. B4 CHECK THE B+ AND IGN START/RUN VOLTAGE TO PCM POWER RELAY 
    • Ignition OFF.
    • PCM Power Relay connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) PCM Power Relay Connector, Harness Side (-)
      B+ Ground
      IGN START/RUN Ground

    Are the voltages greater than 10 V? 

    Yes No
    GO to  B5. REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test.
  5. B5 CHECK THE PCMRC CIRCUIT FOR AN OPEN 
    • Ignition OFF.
    • PCM connector disconnected.
    • Measure the resistance between:
      (+) PCM Power Relay Connector, Harness Side (-) PCM Connector, Harness Side
      PCMRC PCMRC

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  B6. REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test.
  6. B6 CHECK THE PCMRC CIRCUIT FOR A SHORT TO VOLTAGE 
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) PCM Connector, Harness Side (-)
      PCMRC Ground

    Is any voltage present? 

    Yes No
    REPAIR the short circuit. Clear the PCM DTCs.
    REPEAT the self-test.    		 GO to  B7.
  7. B7 CHECK THE ISP-R VOLTAGE AT THE PCM HARNESS CONNECTOR 
    • Ignition OFF.
    • PCM Power Relay connector connected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) PCM Connector, Harness Side (-)
      ISP-R Ground

    Is the voltage greater than 10 V? 

    Yes No
    GO to  B8. REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test.
  8. B8 CHECK FOR AN OPEN VPWR CIRCUIT BETWEEN THE PCM AND POWER RELAY 
    • Ignition OFF.
    • PCM connector disconnected.
    • Measure the resistance between:
    (+) PCM Power Relay Connector, Harness Side (-) PCM Connector, Harness Side
    VPWR VPWR

    Is the resistance less than 5 ohms? 

    Yes No
    For DTC P068A, GO to  B14.
    For all others, INSTALL a new PCM Power relay.
    Clear the PCM DTCs. REPEAT the self-test.    		 REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test.
  9. B9 CHECK THE PCMRC CIRCUIT FOR A SHORT TO GROUND 
    • Ignition OFF.
    • PCM Power Relay connector disconnected.
    • PCM connector disconnected.
    • Measure the resistance between:
      (+) PCM Connector, Harness Side (-)
      PCMRC Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  B10. REPAIR the short circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  10. B10 CHECK THE ISP-R CIRCUIT FOR A SHORT TO VOLTAGE 
    • Ignition OFF.
    • Measure the voltage between:
      (+) PCM Connector, Harness Side (-)
      ISP-R Ground

    Is any voltage present? 

    Yes No
    REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test. For Edge 2.0L,
    Explorer 2.0L,
    F-150 3.5L,
    Flex 3.5L GTDI,
    Focus,
    MKS 3.5L,
    MKT 3.5L, and
    Taurus 3.5L GTDI, GO to  B12.
    For all others, GO to  B11.
  11. B11 CHECK THE INJPWRM CIRCUIT FOR AN OPEN 
    • INJ connector disconnected.
    • Measure the resistance between:
      (+) PCM Connector, Harness Side (-) INJ Connector, Harness Side
      INJPWRM VPWR

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  B14. REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test.
  12. B12 CHECK THE INJPWR_M PID 
    • Ignition OFF.
    • PCM Power Relay connector connected.
    • PCM connector connected.
    • Ignition ON, engine OFF.
    • Access the PCM and monitor the INJPWR_M (VOLT) PID.
    • Record the INJPWR_M PID value.
    • Ignition OFF.
    • Record the INJPWR_M PID value.

    Is the INJPWR_M PID voltage reading above 10 V with ignition ON and 0 V with the ignition OFF? 

    Yes No
    GO to  B14. REPAIR the circuit.
    Clear the PCM DTCs. REPEAT the self-test.
  13. B13 CHECK THE ISP-R VOLTAGE AT THE PCM HARNESS CONNECTOR 
    • Ignition OFF.
    • PCM connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) PCM Connector, Harness Side (-)
      ISP-R Ground

    Is the voltage greater than 10 V? 

    Yes No
    GO to  B14. REPAIR the open circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  14. B14 CHECK FOR CORRECT PCM OPERATION 
    • Ignition OFF.
    • 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.
    • 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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