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SFI System: Precaution: Precaution

  1. INITIALIZATION 
    NOTE:
    • Perform REGISTRATION (VIN registration) when replacing the ECM. Refer to REGISTRATION .
    • Perform initialization (throttle position) after replacing the throttle body assembly or cleaning any throttle body components. Refer to ON-VEHICLE INSPECTION .
    • Perform initialization (throttle position) after reconnecting the auxiliary battery cable or replacing the ECM. Refer to ON-VEHICLE INSPECTION .
  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 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 service 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
      GTY218698Courtesy 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: Disconnecting Battery Cable
    GTY325891Courtesy 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 Negative (-) Auxiliary Battery Terminal
      *2 Cable
    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.
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