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Home >> Lexus >> 2008 >> LX 570 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTC P0128 - P0453 >> DTC P0230 Fuel Pump Primary Circuit >> Inspection Procedure
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Inspection Procedure

This troubleshooting procedure is based on the premise that the engine is started. If the engine is not started, proceed to the Problem Symptoms Table (See PROBLEM SYMPTOMS TABLE ).

  1. CHECK FOR DTC (B1500) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Combination Meter / Trouble Codes.
    5. Read the DTC.

    Result 

    RESULT REFERENCE

    Result Proceed to
    DTC B1500 is not output A
    DTC B1500 is output B

    B: GO TO DTC B1500  (See DTC B1500 FUEL SENDER OPEN DETECTED )

    A: Go to Next Step 

  2. PERFORM ACTIVE TEST USING TECHSTREAM (FUEL PUMP) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG) and turn the Techstream on.
    3. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump / Speed.
    4. Check whether operating sounds can be heard while operating the fuel pump using the Techstream.

    OK: Operating sounds can be heard from fuel pump. 

    NG:  Go to step  6

    OK: Go to Next Step 

  3. CHECK HARNESS AND CONNECTOR (FUEL PUMP ECU - ECM, BODY GROUND) 
    1. Disconnect the N2 fuel pump ECU connector.
    2. Disconnect the A38 ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    N2-5 (FPC) - A38-52 (FPC) Always Below 1 Ω
    N2-4 (DI) - A38-18 (DI) Always Below 1 Ω
    N2-6 (E) - Body ground Always Below 1 Ω
    N2-1 (FP-) - Body ground Always 10 kΩ or higher
    N2-5 (FPC) or A38-52 (FPC) - Body ground Always 10 kΩ or higher
    N2-4 (DI) or A38-18 (DI) - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 1: Identifying Terminals Of N2 Fuel Pump ECU And A38 ECM Connectors
    G05627920Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  4. REPLACE FUEL PUMP ECU 
    1. Replace the fuel pump ECU (See REMOVAL ).
  5. CONFIRM WHETHER DTC OUTPUT RECURS 
    1. Check that there are 17 liters or more of fuel remaining.
    2. Connect the Techstream to the DLC3.
    3. Turn the engine switch on (IG).
    4. Turn the Techstream on.
    5. Clear DTCs (See DTC CHECK/CLEAR ).
    6. Crank the engine for 15 seconds.
    7. Idle it for 1 minute.
    8. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
    9. Read the DTCs.

    Result 

    RESULT REFERENCE

    Result Proceed to
    DTC is not output A
    DTC P0230 is output B

    B: REPLACE ECM  (See ECM )

    A: END 

  6. INSPECT CIRCUIT OPENING RELAY (C/OPN) 
    1. Remove the circuit opening relay (C/OPN) from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    3 - 5 No battery voltage applied to terminals 1 and 2 10 kΩ or higher
    3 - 5 Battery voltage applied to terminals 1 and 2 Below 1 Ω
    Fig 2: Inspecting Circuit Opening Relay (C/Opn)
    G04942976Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE CIRCUIT OPENING RELAY (C/OPN) 

    OK: Go to Next Step 

  7. INSPECT CIRCUIT OPENING RELAY (POWER SOURCE VOLTAGE) 
    1. Remove the circuit opening relay (C/OPN) from the engine room relay block.
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

    Standard Voltage 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Switch Condition Specified Condition
    C/OPN relay (2) - Body ground Engine switch on (IG) 11 to 14 V
    C/OPN relay (5) - Body ground Engine switch on (IG) 11 to 14 V

    NG:  Go to step  14

    Fig 3: Identifying Terminals Of Engine Room Relay Block
    G05149753Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  8. CHECK HARNESS AND CONNECTOR (CIRCUIT OPENING RELAY (C/OPN) - ECM, FUEL PUMP ECU) 
    1. Remove the circuit opening relay (C/OPN) from the engine room relay block.
    2. Disconnect the A38 ECM connector.
    3. Disconnect the N2 fuel pump ECU connector.
    4. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    C/OPN relay (1) - A38-48 (FC) Always Below 1 Ω
    C/OPN relay (3) - N2-3 (+B) Always Below 1 Ω
    C/OPN relay (1) or A38-48 (FC) - Body ground Always 10 kΩ or higher
    C/OPN relay (3) or N2-3 (+B) - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 4: Identifying Terminals Of N2 Fuel Pump ECU And A38 ECM Connectors
    G05627923Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  9. CHECK HARNESS AND CONNECTOR (FUEL PUMP - FUEL PUMP ECU) 
    1. Disconnect the N1 fuel pump connector.
    2. Disconnect the N2 fuel pump ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    N1-4 (B2) - N2-2 (FP) Always Below 1 Ω
    N1-5 (E2) - N2-1 (FP-) Always Below 1 Ω
    N1-4 (B2) or N2-2 (FP) - Body ground Always 10 kΩ or higher
    N1-5 (E2) or N2-1 (FP-) - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 5: Identifying Terminals Of N1 Fuel Pump And N2 Fuel Pump ECU Connectors
    G05627924Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  10. INSPECT FUEL PUMP 
    1. Inspect the fuel pump (See INSPECTION ).

    NG: REPLACE FUEL PUMP  (See INSPECTION )

    OK: Go to Next Step 

  11. CHECK HARNESS AND CONNECTOR (FUEL PUMP ECU - ECM, BODY GROUND) 
    1. Disconnect the N2 fuel pump ECU connector.
    2. Disconnect the A38 ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    N2-5 (FPC) - A38-52 (FPC) Always Below 1 Ω
    N2-4 (DI) - A38-18 (DI) Always Below 1 Ω
    N2-6 (E) - Body ground Always Below 1 Ω
    N2-5 (FPC) or A38-52 (FPC) - Body ground Always 10 kΩ or higher
    N2-4 (DI) or A38-18 (DI) - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 6: Identifying Terminals Of N2 Fuel Pump ECU And A38 ECM Connectors
    G05627925Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  12. REPLACE FUEL PUMP ECU 
    1. Replace the fuel pump ECU (See REMOVAL ).
  13. CONFIRM WHETHER DTC OUTPUT RECURS 
    1. Check that there is 17 liters or more of fuel remaining.
    2. Connect the Techstream to the DLC3.
    3. Turn the engine switch on (IG).
    4. Turn the Techstream on.
    5. Clear DTCs (See DTC CHECK/CLEAR ).
    6. Crank the engine for 15 seconds.
    7. Idle it for 1 minute.
    8. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
    9. Read the DTCs.

    Result 

    RESULT REFERENCE

    Result Proceed to
    DTC is not output A
    DTC P0230 is output B

    B: REPLACE ECM  (See ECM )

    A: END 

  14. CHECK HARNESS AND CONNECTOR (C/OPN RELAY - EFI NO. 2 RELAY, IGN FUSE) 
    1. Remove the circuit opening relay (C/OPN) from the engine room relay block.
    2. Remove the EFI NO. 2 relay (EFI NO. 2) from the engine room relay block.
    3. Remove the IGN fuse from the engine room relay block.
    4. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    C/OPN relay (2) - IGN fuse (2) Always Below 1 Ω
    C/OPN relay (5) - EFI NO. 2 relay (3) Always Below 1 Ω
    C/OPN relay (2) or IGN fuse (2) - Body ground Always 10 kΩ or higher
    C/OPN relay (5) or EFI NO. 2 relay (3) - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 7: Identifying Terminals Of EFI No. 2 Relay
    G05628172Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  15. INSPECT EFI NO. 2 RELAY (EFI NO. 2) 
    1. Remove the EFI NO. 2 relay (EFI NO. 2) from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    3 - 5 No battery voltage applied to terminals 1 and 2 10 kΩ or higher
    3 - 5 Battery voltage applied to terminals 1 and 2 Below 1 Ω
    Fig 8: Inspecting EFI No. 2 Relay (EFI No. 2)
    G04942976Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE EFI NO. 2 RELAY (EFI NO. 2) 

    OK: Go to Next Step 

  16. CHECK HARNESS AND CONNECTOR (EFI NO. 2 RELAY - INTEGRATION RELAY, BATTERY, BODY GROUND) 
    1. Remove the EFI MAIN 2 fuse from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      EFI MAIN 2 fuse Always Below 1 Ω
    3. Reinstall the EFI MAIN 2 fuse.
    4. Remove the EFI NO. 2 relay (EFI NO. 2) from the engine room relay block.
    5. Remove the integration relay from the engine room relay block.
    6. Disconnect the 1B integration relay connector.
    7. Disconnect the cable from the battery positive (+) terminal.
    8. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    EFI NO. 2 relay (1) - 1B-4 Always Below 1 Ω
    EFI NO. 2 relay (5) - Positive (+) battery cable Always Below 1 Ω
    EFI NO. 2 relay (2) - Body ground Always Below 1 Ω
    EFI NO. 2 relay (1) or 1B-4 - Body ground Always 10 kΩ or higher
    EFI NO. 2 relay (5) or Positive (+) battery cable - Body ground Always 10 kΩ or higher
    Fig 9: Identifying EFI Main 2 Fuse
    G05627928Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: GO TO ECM POWER SOURCE CIRCUIT  (See ECM POWER SOURCE CIRCUIT )

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