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Precaution [12/2018 - 07/2020]

WARNING: This page is about a different variant/trim than selected.
  1. PRECAUTIONS FOR INSPECTING HYBRID CONTROL SYSTEM 
    1. Before the following operations are conducted, take precautions to prevent electric shock by turning the power switch off, wearing insulated gloves, and removing the service plug grip from HV battery.
      • Inspecting the high-voltage system
      • Disconnecting the low voltage connector of the inverter with converter assembly and hybrid motor control inverter assembly rear
      • Disconnecting the low voltage connector of the HV battery
      GTY588386Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      GTY742514Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE:
      • After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

        Refer to PRECAUTION [12/2018 - 08/2019] , or refer to PRECAUTION [08/2019 - ]

      • After removing the service plug grip, turning the power switch on (READY) may cause a malfunction. Do not turn the power switch on (READY) unless instructed by the repair information.
    2. To prevent electric shock, make sure to remove the service plug grip to cut off the high voltage circuit before servicing the vehicle.
      GTY687067Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. After removing the service plug grip, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.
      GTY703958Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. After removing the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals.

      HINT: 

      Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly and hybrid motor control inverter assembly rear.

      GTY698431Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Without waiting for 10 minutes
    5. Check the voltage at the terminals in the inspection point of the inverter with converter assembly.
      WARNING:

      Be sure to wear insulated gloves.

      1. Remove the connector cover assembly from the inverter with converter assembly.

        Refer to PROCEDURE - STEP 16

        GTY541773Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        NOTE:
        • Do not touch the connector cover assembly waterproof seal.
        • Do not allow any foreign matter or water to enter the inverter with converter assembly.
      2. Measure the voltage according to the value(s) in the table below.
        GTY541774Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard Voltage

        Tester Connection Condition Specified Condition
        Inspection point At least 10 minutes after removing the service plug grip 0 V

        HINT: 

        Make sure to set the tester to DC750 V or more when measuring the voltage.

      3. Reinstall the connector cover assembly.
    6. Check the voltage at the terminals in the inspection point of the hybrid motor control inverter assembly rear.
      WARNING:

      Wear insulated gloves.

      1. Remove the 5 bolts and inverter cover from the hybrid motor control inverter assembly rear.
        GTY804819Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        *a Interlock Connector
        *b Waterproof Seal
        NOTE:
        • Make sure to pull the connector cover assembly straight up, as a connector is connected to the bottom of the connector cover assembly.
        • Do not touch the connector cover assembly waterproof seal.
        • Do not allow any foreign matter or water to enter the hybrid motor control inverter assembly rear.
      2. Using a voltmeter, measure the voltage between the terminals of the 2 phase connectors.

        Standard Voltage

        Tester Connection Condition Specified Condition
        Inspection point At least 10 minutes after removing the service plug grip 0 V
        NOTE:
        • Do not allow any foreign matter or water to enter the hybrid motor control inverter assembly rear.
        • As it may result in an incorrect measurement, do not use terminal (A) when measuring.

        HINT: 

        Make sure to set the tester to DC750 V or more when measuring the voltage.

        GTY810112Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    7. When turning the power switch on (IG) during an inspection, do not press the power switch while depressing the brake pedal.
      WARNING:

      Pressing the power switch with the brake pedal depressed causes the system to enter the READY-on state. This is very dangerous because high voltage may be applied to the inspection area.

      GTY734749Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    8. Turn the power switch off, disconnect the cable from the negative (-) terminal of the auxiliary battery and put on insulated gloves before touching any of the orange-colored wire harnesses and connectors of the high-voltage system.
      NOTE:

      After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

      Refer to PRECAUTION [12/2018 - 08/2019] , or refer to PRECAUTION [08/2019 - ]

    9. Turn the power switch off before performing any resistance checks.
    10. Turn the power switch off before disconnecting or reconnecting any connectors.
    11. When performing work involving high-voltage wires, use either a tool wrapped with vinyl insulating tape or an insulated tool.
    12. When high-voltage connectors are removed, wrap the connectors with insulation tape to prevent them from contacting foreign matter.
  2. NOTICE FOR HYBRID CONTROL SYSTEM ACTIVATION 
    1. When the warning light is illuminated, or the auxiliary battery has been disconnected and reconnected, attempting to turn the power switch on (READY) may not start the system (the system may not enter the READY-on state) on the first attempt. If so, turn the power switch off and reattempt to start the hybrid system.
      NOTE:

      After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

      Refer to PRECAUTION [12/2018 - 08/2019] , or refer to PRECAUTION [08/2019 - ]

  3. PRECAUTIONS FOR DISCONNECTING AND RECONNECTING CABLE TO NEGATIVE (-) AUXILIARY BATTERY TERMINAL 
    GTY371121Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *1 Cable
    *2 Negative (-) Battery Terminal
    1. Before performing work on electronic components, disconnect the cable from the negative (-) auxiliary battery terminal to prevent damage to the electrical system or electrical components.
    2. Before disconnecting and reconnecting the cable from the negative (-) auxiliary battery terminal, turn the power switch off and the headlight switch off. Then loosen the terminal nut completely. Do not damage the cable or terminal.
    3. When a cable is disconnected from the negative (-) auxiliary battery terminal, the clock and radio settings and stored DTCs will be cleared. Therefore, before disconnecting the cable, make a note of them.
      NOTE:
      • After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

        Refer to PRECAUTION [12/2018 - 08/2019] , or refer to PRECAUTION [08/2019 - ]

      • When the cable is disconnected from the negative (-) auxiliary battery terminal, initialize the following systems after the cable is reconnected.
        System Name See Procedure
        Lane Departure Alert System (w/ Steering Control) Refer to INITIALIZATION [12/2018 - 08/2019] , or refer to INITIALIZATION [08/2019 - 07/2020]
        Intelligent Clearance Sonar System
        Simple Advanced Parking Guidance System
        Pre-collision System
        Power Door Lock Control System
        AFS (Adaptive Front-lighting System)
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