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Inspection Procedure

  1. PERFORM ACTIVE TEST BY TECHSTREAM (OPERATE C/OPN RELAY) 
    1. Connect Techstream to the DLC3.
    2. Turn the ignition switch to the ON position and turn Techstream ON.
    3. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump / Speed.
    4. Check the operation of the relay while operating it using the Techstream.

      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 

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

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

    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 SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      3 - 5 10 kΩ or higher
      3 - 5 Below 1 Ω (Apply battery voltage between terminals 1 and 2)
    3. Fig 2: Measuring C/Opn Relay Resistance
      G04942976Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE C/OPN RELAY 

    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 SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      FC (H34-8) - E1 (H31-5) 9 to 14 V
    3. Fig 3: Identifying Terminals Of H34 And H31 HV Control ECU Connectors
      G05275753Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE HV CONTROL ECU 

    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.
          Fig 4: Identifying Terminals Of F16 Fuel Pump Connector
          G05275754Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FUEL PUMP 

    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 SPECIFIED CONDITION CHART

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

        Standard resistance (Check for short) 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        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 SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        Fuel pump (F16-5) - Body ground 10 kΩ or higher
      Fig 5: Identifying Terminals Of F16 Fuel Pump Connector
      G05275755Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE C/OPN RELAY