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Inspection Procedure

  1. PERFORM ACTIVE TEST BY INTELLIGENT TESTER (OPERATE C/OPN RELAY) 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the ignition switch to the ON position and turn the intelligent tester ON.
    3. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / FUEL PUMP / SPD.
    4. Check the operation of the relay while operating it using the intelligent tester.

      OK: Operating noise can be heard from the relay. 

    OK: GO TO step   6 

    NG: Go to next step 

  2. INSPECT ECM POWER SOURCE CIRCUIT 

    NG: REPAIR OR REPLACE POWER SOURCE CIRCUIT COMPONENTS 

    OK: Go to next step 

  3. INSPECT FUSE (IGCT NO. 3 FUSE) 
    1. Remove the IGCT No. 3 fuse from the R/B No. 3.
    2. Measure the resistance in the IGCT No. 3 fuse.

      Standard resistance: 

      Below 1 Ω 

    NG: CHECK FOR SHORT IN ALL HARNESS AND COMPONENTS CONNECTED TO FUSE 

    Fig 1: Identifying IGCT No 3 Fuse
    G05200211Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  4. INSPECT C/OPN RELAY 
    1. Remove the C/OPN relay from the engine room R/B.
    2. Measure the C/OPN relay resistance.

      Standard resistance 

      TESTER CONNECTION AND SPECIFIED CONDITION

      Tester Connection Specified Condition
      3 - 5 10 kΩ or higher
      3 - 5 Below 1 Ω (Apply battery voltage between terminals 1 and 2)

    NG: REPLACE C/OPN RELAY 

    Fig 2: Inspecting C/OPN Relay
    G04942976Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  5. INSPECT HV CONTROL ECU (FC VOLTAGE) 
    1. Turn the ignition switch to the ON position.
    2. Measure the voltage between the terminals of the H34 and H31 HV control ECU connectors.

      Standard voltage 

      TESTER CONNECTION AND SPECIFIED CONDITION

      Tester Connection Specified Condition
      FC (H34-8) - E1 (H31-5) 9 to 14 V

    OK: REPLACE HV CONTROL ECU 

    Fig 3: Identifying H34 And H31 HV Control ECU Connectors
    G05275753Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: CHECK AND REPAIR HARNESS AND CONNECTOR (HV CONTROL ECU - CIRCUIT OPENING RELAY) 

  6. INSPECT FUEL PUMP 
    1. Inspect fuel pump resistance.
      1. Measure the resistance between terminals 4 and 5.

        Standard resistance: 

        0.2 to 3.0 Ω at 20°C (68°F) 

    2. Inspect fuel pump operation.
      1. Apply battery voltage to both the terminals. Check that the pump operates.
        NOTE:
        • These tests must be done quickly (within 10 seconds) to prevent the coil from burning out.
        • Keep fuel pump as far away from the battery as possible.
        • Always switch at the battery side.

    NG: REPLACE FUEL PUMP 

    Fig 4: Identifying Fuel Pump Connector Terminals
    G05275754Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (FUEL PUMP - C/OPN RELAY) 
    1. Check the harness and the connectors between the fuel pump and the C/OPN relay.
      1. Disconnect the fuel pump connector.
      2. Remove the C/OPN relay from the engine room R/ B.
      3. Measure the resistance according to the value(s) in the table below.

        Standard resistance (Check for open) 

        TESTER CONNECTION AND SPECIFIED CONDITION

        Tester Connection Specified Condition
        Fuel pump (F16-4) - C/OPN relay (3) Below 1 Ω

        Standard resistance (Check for short) 

        TESTER CONNECTION AND SPECIFIED CONDITION

        Tester Connection Specified Condition
        Fuel pump (F16-4) or C/OPN (3) - Body ground 10 kΩ or higher
    2. Check the harness and the connectors between the fuel pump and the body ground.
      1. Disconnect the fuel pump connector.
      2. Measure the resistance according to the value(s) in the table below.

        Standard resistance (Check for open) 

        TESTER CONNECTION AND SPECIFIED CONDITION

        Tester Connection Specified Condition
        Fuel pump (F16-5) - Body ground 10 kΩ or higher

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      Fig 5: Identifying C/OPN Relay From Engine Room R/ B
      G05275755Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: REPLACE C/OPN RELAY