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HOMESERVICE MANUALSFORD2004MUSTANG BASE, 2D COUPE, 3.9 6, AUTOMATICREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 2546 (ENGINE CONTROLS - PINPOINT TEST JB: SECONDARY IGNITION (COP) THROUGH PINPOINT TEST KF: FAN CONTROL (FC) RELAYS - (EXCEPT DIESEL & HYBRID))PINPOINT TEST KC: FUEL PUMP CONTROL MODULETEST PROCEDURE
2004 Ford Mustang Base, 2D Coupe, 3.9 6, Automatic

Test Procedure

2004 Ford Mustang Base, 2D Coupe, 3.9 6, AutomaticSECTION Test Procedure
WARNING: This page does not describe the selected car, but rather 28 other vehicles, including the 2011 Mercury Milan, 2011 Mercury Mariner, 2011 Mercury Grand Marquis, 2011 Lincoln Town Car, and 2011 Lincoln Navigator. However, it is still accessible from the selected car via links, so may be relevant.
  1. KC1 CHECK FOR DIAGNOSTIC TROUBLE CODES (DTCS) 

    Are DTCs P025A, P025B, P025C, P025D, P027A, P027B, P0627, P2632, U0109, U016C, U210B, or U0210C present? 

    Yes No
    For continuous memory DTCs P025A, P025B, P025C, P025D, P027A, P027B, P0627, P2632, U0109, U016C, U210B or U210C, GO to  KC2.
    For KOEO and KOER DTCs P025A, P025B, P025C, P025D, P027A or P027B, GO to  KC3.
    For KOEO and KOER DTCs P0627 or P2632, GO to  KC8.
    For KOEO  and KOER DTCs U0109 or U016C, GO to  KC14.
    For KOEO  and KOER DTCs U210B or U210C, GO to  KC28.    		 For all others, GO to DIAGNOSTIC TROUBLE CODE (DTC) CHARTS AND DESCRIPTIONS .
  2. KC2 CONTINUOUS MEMORY DTCS P025A, P025B, P025C, P025D, P027A, P027B, P0627, P2632, U0109, U016C, U210B AND U210C: CHECK FOR KEY ON, ENGINE OFF (KOEO) DTCS 
    • Ignition ON, engine OFF.
    • Clear the PCM DTCs.
    • Carry out the PCM self-test.

    Are DTCs P025A, P025B, P025C, P025D, P027A, P027B, P0627, P2632, U0109, U016C, U210B or U210C present? 

    Yes No
    For DTCs P025A, P025B, P025C, P025D, P027A or P027B, GO to  KC3.
    For DTCs P0627 or P2632, GO to  KC8.
    For DTCs U0109 or U016C, GO to  KC14.
    For DTCs U210B or U210C, GO to  KC29.    		 Unable to duplicate or identify the concern at this time.
    GO to PINPOINT TEST Z .
  3. KC3 DTC P025A, P025B, P025C, P025D, P027A, P027B: CHECK THE FPC CIRCUIT FOR AN OPEN 
    NOTE: The Mustang 5.4L is equipped with two fuel pump control modules. Diagnose the fuel pump control module related to the current DTC.
    • Ignition OFF.
    • Disconnect the fuel pump control module related to the current DTC.
    • PCM connector disconnected.
    • Measure the resistance between:
      RESISTANCE REFERENCE CHART

      (+) Fuel Pump Control Module Connector, Harness Side (-) PCM Connector, Harness Side
      FPC FPC

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  KC4. REPAIR the open circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  4. KC4 CHECK THE FPC CIRCUIT FOR A SHORT TO GROUND 
    • Measure the resistance between:
      RESISTANCE REFERENCE CHART

      (+) Fuel Pump Control Module Connector, Harness Side (-)
      FPC Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  KC5. REPAIR the short circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  5. KC5 CHECK THE FPC CIRCUIT FOR A SHORT TO VOLTAGE 
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      VOLTAGE REFERENCE CHART

      (+) Fuel Pump Control Module Connector, Harness Side (-)
      FPC Ground

    Is any voltage present? 

    Yes No
    REPAIR the short circuit. Clear the PCM DTCs.
    REPEAT the self-test.    		 GO to  KC6.
  6. KC6 CHECK THE FPC CIRCUIT FOR CORRECT RESPONSE 
    • Ignition OFF.
    • Connect the fuel pump control module related to the current DTC.
    • Disconnect the fuel pump control module not related to the current DTC.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      VOLTAGE REFERENCE CHART

      (+) PCM Connector, Harness Side (-)
      FPC Ground

    Is the voltage greater than 10 V? 

    Yes No
    For DTCs P025B or P027B, GO to  KC7.
    For all others, GO to  KC34.    		 INSTALL a new suspect Fuel Pump Control Module. REFER to the appropriate Fuel Charging and Controls article.
    Clear the PCM DTCs. REPEAT the self-test.
  7. KC7 CHECK THE HARNESS FOR ROUTING, ALTERATIONS, INCORRECT SHIELDING, OR ELECTRICAL INTERFERENCE FROM OTHER SYSTEMS 
    • Ignition OFF.
    • Check the harness for the following:
      • damaged insulation
      • corrosion
      • correct routing

    Is a concern present? 

    Yes No
    REPAIR as necessary.
    Clear the PCM DTCs. REPEAT the self-test.    		 GO to  KC34.
  8. KC8 DTCS P0627 OR P2632: CHECK THE SUSPECT FPPWR, SUSPECT FPRTN AND INTERNAL FUEL PUMP CIRCUIT RESISTANCE 
    NOTE: The Mustang 5.4L is equipped with two fuel pump control modules. Diagnose the fuel pump control module related to the current DTC.
    • Ignition OFF.
    • Disconnect the fuel pump control module related to the current DTC.
    • Measure the resistance between:
      RESISTANCE REFERENCE CHART

      (+) Fuel Pump Control Module Connector, Harness Side (-) Fuel Pump Control Module Connector, Harness Side
      Suspect FPPWR Suspect FPRTN

    Is the resistance less than 10 ohms? 

    Yes No
    GO to  KC11. GO to  KC9.
  9. KC9 CHECK THE SUSPECT FPPWR AND SUSPECT FPRTN CIRCUITS FOR AN OPEN 
    • Disconnect the FP related to the current DTC.
    • Measure the resistance between:
      RESISTANCE REFERENCE CHART

      (+) Fuel Pump Control Module Connector, Harness Side (-) FP Connector, Harness Side
      Suspect FPPWR Suspect FPPWR
      Suspect FPRTN Suspect FPRTN

    Are the resistances less than 5 ohms? 

    Yes No
    GO to  KC10. REPAIR the open circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  10. KC10 CHECK THE SUSPECT FP FOR AN OPEN 
    • Measure the resistance between:
      RESISTANCE REFERENCE CHART

      (+) FP Connector, Component Side (-) FP Connector, Component Side
      Suspect FPPWR Suspect FPRTN

    Is the resistance less than 10 ohms? 

    Yes No
    GO to  KC11. INSTALL a new FP. REFER to the appropriate Fuel Tank and Lines article.
    Clear the PCM DTCs. REPEAT the self-test.
  11. KC11 CHECK THE SUSPECT FPPWR CIRCUIT FOR A SHORT TO GROUND 
    • Measure the resistance between:
      RESISTANCE REFERENCE CHART

      (+) Fuel Pump Control Module Connector, Harness Side (-)
      Suspect FPPWR Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  KC12. REPAIR the short circuit. Clear the PCM DTCs.
    REPEAT the self-test.
  12. KC12 CHECK THE SUSPECT FPPWR AND SUSPECT FPRTN CIRCUITS FOR A SHORT TO VOLTAGE 
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      VOLTAGE REFERENCE CHART

      (+) Fuel Pump Control Module Connector, Harness Side (-)
      Suspect FPPWR Ground
      Suspect FPRTN Ground

    Is any voltage present? 

    Yes No
    REPAIR the short circuit. Clear the PCM DTCs.
    REPEAT the self-test.    		 GO to  KC13.
  13. KC13 CHECK THE SUSPECT FUEL PUMP CONTROL MODULE FOR CORRECT OPERATION 
    • Ignition OFF.
    • Connect the fuel pump control module related to the current DTC.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      VOLTAGE REFERENCE CHART

      (+) FP Connector, Harness Side (-) FP Connector, Harness Side
      Suspect FPPWR Suspect FPRTN
    • Access the PCM and control the FP (MODE) PID.
    • Command the FP PID ON.

    Is the voltage greater than 10 V with the PID commanded ON? 

    Yes No
    INSTALL a new FP. REFER to the appropriate Fuel Tank and Lines article.
    Clear the PCM DTCs. REPEAT the self-test.    		 INSTALL a new suspect Fuel Pump Control Module. REFER to the appropriate Fuel Charging and Controls article.
    Clear the PCM DTCs. REPEAT the self-test.
  14. KC14 DTCS U0109 OR U016C: CHECK THE VOLTAGE AND GROUND CIRCUITS TO THE SUSPECT FUEL PUMP CONTROL MODULE 
    NOTE: The Mustang 5.4L is equipped with two fuel pump control modules. Diagnose the fuel pump control module related to the current DTC.
RENDER: 1.0x

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