SFI SYSTEM(w/o EGR System) Fuel Pump Control Circuit

DTC Code DTC Name
Fuel Pump Control Circuit

DESCRIPTION

The fuel pump circuit consists of the ECM, fuel pump and fuel pump control ECU assembly (which operates the fuel pump). Based on the engine output, the ECM determines the fuel pump speed. The speed is then converted to a duty signal and sent to the fuel pump control ECU assembly. Based on the signal sent from the ECM, the fuel pump ECU adjusts the fuel pump operation speed.

WIRING DIAGRAM

A371208E02

CAUTION / NOTICE / HINT

Note:

Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

  1. PERFORM ACTIVE TEST USING GTS (CONTROL THE FUEL PUMP / SPEED)

    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump / Speed.

      Powertrain > Engine and ECT > Active Test

      Tester Display

      Control the Fuel Pump / Speed

    5. Check whether the fuel pump operating sounds occurs when performing the Active Test on the GTS.

      Result

      Result

      Proceed to

      Fuel pump operating sound does not occur

      A

      Fuel pump operating sound occurs

      B
    B

    PERFORM ACTIVE TEST USING GTS (CONTROL THE FUEL PUMP DUTY)Click here

    A

  2. CHECK TERMINAL VOLTAGE (POWER SOURCE OF FUEL PUMP CONTROL ECU ASSEMBLY)

    1. A330727C16

      *a

      Front view of wire harness connector

      (to Fuel Pump Control ECU Assembly)

      Disconnect the fuel pump control ECU Assembly connector.

    2. Turn the power switch on (IG).

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      N19-1 (+B) - N19-4 (E)

      Power switch on (IG)

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    NG

    CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - BODY GROUND)Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (FUEL PUMP - FUEL PUMP CONTROL ECU ASSEMBLY)

    1. Disconnect the fuel pump control ECU assembly connector.

    2. Disconnect the fuel pump connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      V1-4 (B) - N19-6 (FP)

      Always

      Below 1 Ω

      V1-5 (E) - N19-5 (FP-)

      Always

      Below 1 Ω

      V1-4 (B) or N19-6 (FP) - Body ground and other terminals

      Always

      10 kΩ or higher

      V1-5 (E) or N19-5 (FP-) - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. INSPECT FUEL PUMP

    1. Inspect the fuel pump.

      Click here

      Tip:

      Perform "Inspection After Repair" after replacing the fuel pump.

      Click here

    Result

    Proceed to

    OK

    NG
    OK

    CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - ECM)Click here

    NG

    REPLACE FUEL PUMP

    Click here

  5. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - BODY GROUND)

    1. Disconnect the fuel pump control ECU assembly connector.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      N19-4 (E) - Body ground

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. INSPECT A/F RELAY

    1. Inspect the A/F relay.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE A/F RELAY

    OK

  7. CHECK HARNESS AND CONNECTOR (ENGINE ROOM RELAY BLOCK - FUEL PUMP CONTROL ECU ASSEMBLY, AUXILIARY BATTERY)

    A375545C01

    *1

    Engine Room Relay Block and Junction Block Assembly

    *2

    EFI-MAIN Relay

    *3

    A/F Relay

    1. Remove the EFI-MAIN relay from the engine room relay block and junction block assembly.

    2. Remove the A/F relay from the engine room relay block and junction block assembly.

    3. Disconnect the fuel pump control ECU assembly connector.

    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      1 (A/F relay) - 3 (EFI-MAIN relay)

      Always

      Below 1 Ω

      2 (A/F relay) - Body ground

      Always

      Below 1 Ω

      3 (A/F relay) - N19-1 (+B)

      Always

      Below 1 Ω

      1 (A/F relay) or 3 (EFI-MAIN relay) - Body ground

      Always

      10 kΩ or higher

      3 (A/F relay) or N19-1 (+B) - Body ground

      Always

      10 kΩ or higher

    5. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      5 (A/F relay) - Body ground

      Always

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    OK

    GO TO ECM POWER SOURCE CIRCUIT

    Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  8. PERFORM ACTIVE TEST USING GTS (CONTROL THE FUEL PUMP DUTY)

    1. Remove the fuel suction tube assembly.

      Click here

    2. Clean the fuel suction tube assembly to completely remove any remaining fuel.

    3. Remove the fuel pump.

      Click here

    4. Connect the fuel pump and fuel suction tube assembly connectors.

      Note:

      Confirm that no fuel remains inside or on the outside of the fuel pump.

    5. Connect the GTS to the DLC3.

    6. Turn the power switch on (IG).

    7. Turn the GTS on.

    8. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump Duty.

      Powertrain > Engine and ECT > Active Test

      Tester Display

      Control the Fuel Pump Duty
    9. A285444C02

      *a

      Component with harness connected

      (Fuel Pump)

      Operate the fuel pump using the Active Test measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection

      GTS Operation

      Specified Condition

      1 - 2

      Fuel pump control duty: 25%

      3.2 to 4.05 V

      Fuel pump control duty: 80%

      8.8 to 12.5 V

    10. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump / Speed.

      Powertrain > Engine and ECT > Active Test

      Tester Display

      Control the Fuel Pump / Speed

    11. Operate the fuel pump using the Active Test function and measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection

      GTS Operation

      Specified Condition

      1 - 2

      ON (Fuel pump control duty: 90%)

      9.0 to 14.0 V
      Tip:

      • Be sure to measure the voltage with all the connectors connected.

      • Before performing this inspection, check that the battery voltage is between 11 and 14 V (not depleted).

    Result

    Proceed to

    OK

    NG
    NG

    INSPECT FUEL PUMPClick here

    OK

  9. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - ECM)

    1. Disconnect the fuel pump control ECU assembly connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      N19-2 (FPC) - A62-21 (FPC)

      Always

      Below 1 Ω

      N19-2 (FPC) or A62-21 (FPC) - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. REPLACE FUEL PUMP

    1. Replace the fuel pump.

      Click here

      Tip:

      Perform "Inspection After Repair" after replacing the fuel pump.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  11. INSPECT FUEL PUMP

    1. Inspect the fuel pump.

      Click here

      Tip:

      Perform "Inspection After Repair" after replacing the fuel pump.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE FUEL PUMP

    Click here

    OK

  12. CHECK HARNESS AND CONNECTOR (FUEL PUMP - FUEL PUMP CONTROL ECU ASSEMBLY)

    1. Disconnect the fuel pump control ECU assembly connector.

    2. Disconnect the fuel pump connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      V1-4 (B) - N19-6 (FP)

      Always

      Below 1 Ω

      V1-5 (E) - N19-5 (FP-)

      Always

      Below 1 Ω

      V1-4 (B) or N19-6 (FP) - Body ground and other terminals

      Always

      10 kΩ or higher

      V1-5 (E) or N19-5 (FP-) - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  13. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - BODY GROUND)

    1. Disconnect the fuel pump control ECU assembly connector.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      N19-4 (E) - Body ground

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  14. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - ECM)

    1. Disconnect the fuel pump control ECU assembly connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      N19-2 (FPC) - A62-21 (FPC)

      Always

      Below 1 Ω

      N19-2 (FPC) or A62-21 (FPC) - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  15. REPLACE FUEL PUMP CONTROL ECU ASSEMBLY

    1. Replace the fuel pump control ECU assembly.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

  16. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

    1. Check the fuel pump operation.

      OK

      Malfunction has been repaired successfully.

    Result

    Proceed to

    OK

    NG
    OK

    END

    NG

    REPLACE ECM

    Click here