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On-Vehicle Inspection

  1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL 
    WARNING:

    Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to prevent airbag and seat belt pretensioner activation.

  2. REMOVE COOL AIR INTAKE DUCT SEAL  See step  5
  3. REMOVE ENGINE ROOM SIDE COVER LH  See step  6
  4. REMOVE INTEGRATION NO. 1 RELAY 
    1. Remove the engine room No. 1 relay block cover.
      2. Fig 1: Identifying Integration Relay
      GTY147012Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Unit A:
      1. Using a screwdriver, detach the 2 claws and disconnect the integration relay from the engine room No. 2 relay block.

        HINT: 

        Tape the screwdriver tip before use.

      2. Disconnect the 3 connectors.
    3. Unit C:
      1. Using a screwdriver, detach the 2 claws and disconnect the integration relay from the engine room No. 2 relay block.

        HINT: 

        Tape the screwdriver tip before use.

      2. Disconnect the 3 connectors.
  5. INSPECT INTEGRATION NO. 1 RELAY (UNIT A) 
    NOTE:
    • Some relays are built into the integration relay (unit A). The integration relay cannot be disassembled. If there is a malfunction in the circuit of the integration relay, replace the integration relay.
    • The internal circuit of the integration relay is as shown in the illustration. Inspect the integration relay using the following procedures.
      Fig 2: Integration Relay Internal Circuit Diagram
      GTY147007Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Measure the resistance of the C/OPN relay.
      Fig 3: Identifying Integration Relay Backside
      GTY145407Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Connect the battery's positive (+) lead to terminal 1T-8 and negative (-) lead to terminal 1S-3. Check the resistance between the terminals when battery voltage is applied between the terminals.

        Standard resistance

        Tester Connection Specified Condition
        1R-1 - 1S-7 Below 1 Ω
        1R-1 - 1S-8 10 kΩ or higher
      2. Connect the battery's positive (+) lead to terminals 1T-8 and 1R-1, and negative (-) lead to terminal 1S-3 and 1S-7. Measure the resistance between terminals 1R-1 and 1S-8 when battery voltage is applied between the terminals.

        Standard resistance

        Tester Connection Specified Condition
        1R-1 - 1S-8 Below 1 Ω
    2. Measure the resistance of the EFI MAIN relay.
      Fig 4: Identifying EFI Fuse
      GTY140488Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Remove the EFI fuse. Measure the resistance between the terminals.

        Standard resistance

        Tester Connection Specified Condition
        1T-6 - 1T-7 Below 1 Ω
        EFI fuse terminal 2 - terminal 1T-8 10 kΩ or higher
      2. Connect the battery's positive (+) lead to terminal 1T-6 and negative (-) lead to terminal 1T-7. Measure the resistance between EFI fuse terminal 2 and terminal 1T-8 when battery voltage is applied between the terminals.

        Standard resistance

        Tester Connection Specified Condition
        EFI fuse terminal 2 - terminal 1T-8 Below 1 Ω
    3. Measure the resistance of the EFI NO. 2 relay.
      Fig 5: Identifying Integration Relay Connector Terminals
      GTY145408Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Measure the resistance between the terminals.

        Standard resistance

        Tester Connection Specified Condition
        1T-8 - 1S-3 Below 1 Ω
        1S-7 - 1R-1 10 kΩ or higher
      2. Connect the battery's positive (+) lead to terminal 1T-8 and negative (-) lead to terminal 1S-3. Measure the resistance between terminals 1S-7 and 1R-1 when battery voltage is applied between the terminals.

        Standard resistance

        Tester Connection Specified Condition
        1S-7 - 1R-1 Below 1 Ω
    4. Measure the resistance of the INJ relay.
      Fig 6: Identifying INJ Fuse
      GTY125314Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Remove the INJ fuse. Measure the resistance between the terminals.

        Standard resistance

        Tester Connection Specified Condition
        1T-1 - 1T-3 Below 1 Ω
        INJ fuse terminal 2 - terminal 1T-4 10 kΩ or higher
      2. Connect the battery's positive (+) lead to terminal 1T-1 and negative (-) lead to terminal 1T-3. Measure the resistance between INJ fuse terminals 2 and terminal 1T-4 when battery voltage is applied between the terminals.

        Standard resistance

        Tester Connection Specified condition
        INJ fuse terminal 2 - terminal 1T-4 Below 1 Ω
  6. INSPECT INTEGRATION NO. 2 RELAY (UNIT C) 
    NOTE:
    • Some relays are built into the integration relay (unit C). The integration relay cannot be disassembled. If there is a malfunction in the circuit of the integration relay, replace the integration relay.
    • The internal circuit of the integration relay is as shown in the illustration. Inspect the integration relay using the following procedures.
      Fig 7: Integration Relay Internal Circuit Diagram
      GTY147008Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Measure the resistance of the A/F relay.
      Fig 8: Identifying A/F Fuse
      GTY141839Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Remove the A/F fuse. Measure the resistance between the terminals.

        Standard resistance

        Tester Connection Specified Condition
        1U-1 - 1U-3 Below 1 Ω
        A/F fuse terminal 2 - terminal 1U-4 10 kΩ or higher
      2. Connect the battery's positive (+) lead to terminal 1U-1 and negative (-) lead to terminal 1U-3. Measure the resistance between A/F fuse terminals 2 and terminal 1U-4 when battery voltage is applied between the terminals.

        Standard resistance

        Tester Connection Specified condition
        A/F fuse terminal 2 - terminal 1U-4 Below 1 Ω
  7. INSTALL INTEGRATION NO. 1 RELAY 
    1. Unit A:
      1. Connect the 3 connectors.
      2. Attach the integration relay to the engine room No. 2 relay block.
    2. Unit C:
      1. Connect the 3 connectors.
      2. Attach the integration relay to the engine room No. 2 relay block.
    3. Install the engine room No. 1 relay block cover.
  8. INSTALL ENGINE ROOM SIDE COVER LH  See step  32
  9. INSTALL COOL AIR INTAKE DUCT SEAL  See step  34
  10. CONNECT CABLE TO NEGATIVE BATTERY TERMINAL 
  11. PERFORM INITIALIZATION 
    1. Perform initialization. Refer to INITIALIZATION .
      NOTE:

      Certain systems need to be initialized after disconnecting and reconnecting the cable from the negative (-) battery terminal.

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