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Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus RX 350. However, it is still accessible from the selected car via links, so may be relevant.
  1. READ VALUE OF INTELLIGENT TESTER 
    1. Connect the intelligent tester (with CAN VIM) to the DLC3.
    2. Turn the ignition switch to the ON position and turn the intelligent tester main switch on.
    3. Select KEY SW in the DATA LIST and read the value displayed on the intelligent tester.

      Transponder key ECU: 

      DATA LIST - TRANSPONDER KEY ECU

      Item Measurement Item/Display (Range) Normal Condition Diagnostic Note
      KEY SW Unlock warning switch signal/ON or OFF ON: Key is in ignition key cylinder
      OFF: No key is in ignition key cylinder      		 -

      OK: ON (Key is in the ignition key cylinder) appears on the screen. 

    OK: REPLACE TRANSPONDER KEY ECU ASSEMBLY 

    NG: Go to next step. 

  2. INSPECT UNLOCK WARNING SWITCH ASSEMBLY 
    1. Remove the unlock warning switch.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION AND SPECIFIED CONDITION TABLE

      Tester Connection Switch Condition Specified Condition
      1 - 2 Switch pushed (Key set) Below 1 Ω
      Switch free (Key removed) 10 kΩ or higher
      Fig 1: Identifying Unlock Warning Switch Assembly Connector Terminals
      G04966241Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE UNLOCK WARNING SWITCH ASSEMBLY 

    OK: Go to next step. 

  3. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU ASSEMBLY - UNLOCK WARNING SW ASSEMBLY) 
    1. Disconnect the T9 ECU and K4 switch connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION AND SPECIFIED CONDITION TABLE

      Tester Connection Specified Condition
      T9-3 (KSW) - K4-2 Below 1 Ω
      T9-3 (KSW) - Body ground 10 kΩ or higher
      Fig 2: Identifying T9 & K4 Connector Terminals
      G05273591Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step. 

  4. CHECK HARNESS AND CONNECTOR (UNLOCK WARNING SW ASSEMBLY - BODY GROUND) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION AND SPECIFIED CONDITION TABLE

      Tester Connection Specified Condition
      K4-1 - Body ground Below 1 Ω
      Fig 3: Identifying K4 Connector Terminals
      G05273592Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE TRANSPONDER KEY ECU ASSEMBLY 

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