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Inspection Procedure

CAUTION:
  • Before inspecting the high-voltage system, 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.
  • After disconnecting the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals.

HINT:

  1. CHECK AUXILIARY BATTERY 
    1. Measure the voltage between the terminals of the auxiliary battery.

      Standard voltage: 

      12.0 to 12.8 V (Battery electrolyte temperature: 20°C) 

    NG: CHARGE OR REPLACE AUXILIARY BATTERY 

    OK: GO TO Next Step 

  2. CHECK HARNESS AND CONNECTOR (IGCT VOLTAGE) 
    CAUTION: Be sure to wear insulated gloves.
    1. Remove the service plug grip. (See REMOVAL  )
    2. Remove the luggage compartment trim cover front. (See REMOVAL  )
    3. Disconnect the frame wire. (See REMOVAL  )
    4. Remove the battery bracket sub-assembly. (See REMOVAL  )
    5. Connect the auxiliary battery positive terminal cable of the frame wire. (See INSTALLATION  )
    6. Turn the power switch on (IG).
    7. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Specified Condition
      IGCT (N2-1) - GND (N2-5) 8.6 V or higher
      Fig 1: Identifying (N2) Battery Smart Unit Connector Terminals
      G05304827Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE BATTERY SMART UNIT (See  REMOVAL   ) 

    NG: GO TO Next Step 

  3. CHECK FUSE (IGCT NO. 3 FUSE) 
    1. Remove the IGCT No. 3 fuse from the engine room R/B No. 1.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance: 

      Below 1 Ω 

      Fig 2: Identifying IGCT NO.3 FUSE
      G05304828Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FUSE (IGCT NO.3 FUSE) 

    OK: GO TO Next Step 

  4. CHECK HARNESS AND CONNECTOR (BATTERY SMART UNIT - INTEGRATION RELAY (IGCT RELAY)) 
    CAUTION: Be sure to wear insulated gloves.
    1. Install the IGCT No. 3 fuse to the engine room R/B No. 1.
    2. Remove the integration relay from the engine room R/B No. 1.
    3. Disconnect connector N2 from the battery smart unit.
    4. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open) 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      IGCT (N2-1) - 1V-8 Below 1 Ω
      Fig 3: Identifying N2, 1U, 1V And IW Connectors Terminals
      G05192691Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: CHECK AND REPAIR POWER SOURCE CIRCUIT 

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