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SFI System: Precaution: Precaution

  1. INITIALIZATION 
    NOTE:

    Perform REGISTRATION (VIN registration) when replacing the ECM. Refer to REGISTRATION .

  2. PRECAUTIONS FOR INSPECTING HYBRID CONTROL SYSTEM 
    1. Before inspecting the high-voltage system or disconnecting the low voltage connector of the inverter with converter assembly, take safety precautions such as wearing insulated gloves and removing the service plug grip to prevent electrical shocks. 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.
      NOTE:
      • After turning 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 .
      • 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. After disconnecting the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals.
      Fig 1: Identifying Service Plug Grip
      GTY339814Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT: 

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

  3. 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.
  4. FOR USING TECHSTREAM 
    WARNING:

    Observe the following items for safety reasons:

    • Before using the Techstream, read the instruction manual.
    • Prevent the Techstream cable from being caught on the pedals, shift lever or steering wheel when driving with the Techstream connected to the vehicle.
    • When driving the vehicle for testing purposes using the Techstream, 2 persons are required. One is for driving the vehicle, and the other operates the Techstream.
  5. DISCONNECTING AND RECONNECTING NEGATIVE AUXILIARY BATTERY CABLE 
    Fig 2: Identifying Negative Battery Terminal And Cable
    GTY276049Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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.
      TEXT IN ILLUSTRATION

      *1 Cable
      *2 Negative (-) Auxiliary Battery Terminal
    2. Before disconnecting and reconnecting the auxiliary battery cable, 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 the auxiliary battery cable is disconnected, the clock and radio settings and stored DTCs are cleared. Therefore, before disconnecting the auxiliary battery cable, make a note of them.
      NOTE:
      • After turning 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 .
      • When disconnecting the cable from the negative (-) auxiliary battery terminal, initialize the following systems after the cable is reconnected.
      System Name See Procedure
      Advanced Parking Guidance System Refer to PRECAUTION
      Power Door Lock Control System
  6. COOLING FAN SYSTEM 
    NOTE:
    • When the power switch is turned off and the engine temperature is high, the engine water pump assembly and cooling fans may operate for a maximum of 3 minutes depending on the auxiliary battery voltage.
    • After turning the power switch off, keep hands and objects away from the fans when they are operating.

    HINT: 

    • If all of the following are met for a certain period of time during a few minutes immediately before the power switch is turned off, the cooling fans will continue to operate for a maximum of 3 minutes after the engine is stopped. This is performed to ensure restartability.
      • The Techstream indicates a very high coolant temperature.
      • The Techstream indicates a high outside air temperature.