2018 Ford Fusion Energi PlatinumFACTORY OEM SERVICE PROCEDURE

Test Procedure

  1. B1 CHECK FOR DIAGNOSTIC TROUBLE CODES (DTCS) 

    Are DTCs P0686, P0687, P0689, P0690, P2531, P2533 or P2535 present? 

    Yes No
    GO to  B2. RETURN to SYMPTOM CHARTS for further direction.
  2. B2 CHECK FOR BCM DTCS 
    • Carry out the BCM self-test.

    Are any DTCs present? 

    Yes No
    REFER to the Multifunction Electronic Modules article to diagnose the BCM DTCs.
    Clear the PCM DTCs. REPEAT the self-test.    		 GO to  B3.
  3. B3 CHECK THE KEYST PIDS 
    • Ignition ON, engine OFF.
    • Access the PCM and monitor the KEYST (MODE) PID.

    Does the PID indicate ON? 

    Yes No
    GO to  B6. GO to  B4.
  4. B4 CHECK THE ISP-R CIRCUIT 
    • Ignition OFF.
    • PCM connector disconnected.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
    (+) PCM Connector, Harness Side (-)
    ISP-R - Pin B8 Ground

    Is the voltage greater than 10.5 V? 

    Yes No
    GO to  B5. REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test.
  5. B5 CHECK THE ISP-R CIRCUIT FOR A SHORT TO VOLTAGE 
    • Measure the voltage between:
    (+) PCM Connector, Harness Side (-)
    ISP-R - Pin B8 Ground

    Is any voltage present? 

    Yes No
    REPAIR the short circuit. Clear the PCM DTCs.
    REPEAT the self-test.    		 GO to  B13.
  6. B6 CHECK THE B+ VOLTAGE TO PCM POWER RELAY 
    • Ignition OFF.
    • PCM Power Relay connector disconnected.
    • Measure the voltage between:
    (+) PCM Power Relay Connector, Harness Side (-)
    B+ - Pin 1, 3 Ground

    Is the voltage greater than 10.5 V? 

    Yes No
    GO to  B7. REPAIR the open circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  7. B7 CHECK THE PCM POWER RELAY 
    • PCM Power Relay connector disconnected.
    • Carry out the PCM power relay component test. Refer to the appropriate Wiring Diagrams, Component Testing article.

    Is a concern present? 

    Yes No
    INSTALL a new PCM Power Relay. Clear the PCM DTCs. REPEAT the self-test. GO to  B8.
  8. B8 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 - Pin 2 PCMRC - Pin B1

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  B9. REPAIR the open circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  9. B9 CHECK THE PCMRC CIRCUIT FOR A SHORT TO GROUND 
    • Measure the resistance between:
    (+) PCM Power Relay Connector, Harness Side (-)
    PCMRC - Pin 2 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 PCMRC CIRCUIT FOR A SHORT TO VOLTAGE 
    • Ignition ON, engine OFF.
    • Measure the voltage between:
    (+) PCM Power Relay Connector, Harness Side (-)
    PCMRC - Pin 2 Ground

    Is any voltage present? 

    Yes No
    REPAIR the short circuit. Clear the PCM DTCs.
    REPEAT the self-test.    		 GO to  B11.
  11. B11 CHECK FOR AN OPEN VPWR CIRCUIT BETWEEN THE PCM AND THE PCM POWER RELAY 
    • Ignition OFF.
    • Measure the resistance between:
    (+) PCM Power Relay Connector, Harness Side (-) PCM Connector, Harness Side
    VPWR - Pin 5 VPWR - Pin B11, B12

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  B12. REPAIR the open circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  12. B12 CHECK FOR A SHORT TO VOLTAGE ON THE VPWR CIRCUITS BETWEEN THE PCM AND THE PCM POWER RELAY 
    • Ignition ON, engine OFF.
    • Measure the voltage between:
    (+) PCM Power Relay Connector, Harness Side (-)
    VPWR - Pin 5 Ground

    Is any voltage present? 

    Yes No
    REPAIR the short circuit. Clear the PCM DTCs.
    REPEAT the self-test.    		 GO to  B13.
  13. B13 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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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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