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SFI System: Precaution

NOTE: When disconnecting the negative (-) battery cable, initialize the following systems after the terminal is reconnected.
SYSTEM INDEX

System See Procedure
SFI System INITIALIZATION 
Lighting System INITIALIZATION
Power Window Control System
Power Door Lock System
Power Back Door System
Back Door Closer System
Electrical Back Door Outside Handle System
  1. PRECAUTIONS FOR INSPECTING HYBRID CONTROL SYSTEM 
    1. Before inspecting the high-voltage system, take safety precautions to prevent electrical shocks, such as wearing insulated gloves and removing the service plug grip. After removing the service plug grip, put it in your pocket to prevent other technicians from reconnecting it while you are working on the high-voltage system.
      NOTE: Do not put the vehicle into the READY-on state with the service plug grip removed as this may cause a malfunction.
    2. After disconnecting the service plug grip, wait for at least 5 minutes before touching any of the high-voltage connectors or terminals.

      HINT:

      At least 5 minutes are required to discharge the high-voltage capacitor inside the with converter inverter assembly.

      Fig 1: Disconnecting Service Plug Grip
      G05278264Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. After removing the inverter cover, wrap the interlock round terminal for the inverter cover with vinyl tape to prevent it from shorting to ground.
      NOTE: Do not put the vehicle into the READY-on state with the inverter cover removed.
    4. Be sure to prevent water in the reservoir tank from entering the inverter.
    5. Wear protective goggles to prevent eye injury from electrolyte leakage when checking inside the HV battery.
    6. Wear insulated gloves, turn the ignition switch off, and disconnect the negative terminal of the auxiliary battery before touching any of the orange-colored wires of the high-voltage system.
      7. Fig 2: Disconnecting Negative Terminal Of Auxiliary Battery
      G05199968Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    7. Turn the ignition switch off before performing a resistance check.
    8. Turn the ignition switch off before disconnecting or reconnecting any connector.
  2. PRECAUTIONS FOR HYBRID CONTROL SYSTEM ACTIVATION 
    1. When the warning light is illuminated or the auxiliary battery has been disconnected and reconnected, attempting to put the vehicle into the READY-on state the first time may not start the system. If so, turn the ignition switch off and reattempt to put the vehicle into the READY-on state.
  3. PRECAUTIONS FOR INSPECTING, REMOVING, OR INSTALLING WITH CONVERTER INVERTER ASSEMBLY 

    HINT:

    Removing the inverter cover exposes the MG-ECU board. Therefore, perform the following operation when inspecting, removing, or installing the with converter inverter assembly.

    1. When working on the inside of the with converter inverter assembly, temporarily install the inverter cover with a bolt as shown in the illustration.
      Fig 3: Locating Inverter Cover Bolt
      G05199969Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE:
      • Turn the bolt approximately 2 times to prevent deforming the inverter cover. Tightening the bolt excessively will cause deformation on the inverter cover.
      • Use a shop rag or piece of cloth to prevent the inverter cover from coming into contact with the vehicle body and damaging it.
      • Do not apply load to the temporarily installed inverter cover.

      HINT:

      Change the bolt position depending on the area where you are working inside the with converter inverter assembly.

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