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Home >> Lexus >> 2006 >> LS 430 >> Repair and Diagnosis >> Steering >> Steering Column >> Steering Lock System - Diagnostics >> DTC B2780: Push Switch/Key Unlock Warning Switch Malfunction >> Inspection Procedure
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Inspection Procedure

  1. READ VALUE ON HAND-HELD TESTER 
    1. Connect the hand-held tester to the DLC 3.
    2. Turn the hand-held tester on
    3. Select the item below in the DATA LIST, and read its value displayed on the hand-held tester to check the unlock warning switch.
    DATA LIST

    Condition Item Standard
    Push switch is ON PUSH SW "ON" is displayed
    Push switch is OFF PUSH SW "OFF" is displayed
    Smart key is inserted KEY SW "ON" is displayed
    Smart key is not inserted KEY SW "OFF" is displayed

    OK: REPLACE STEERING LOCK ECU (SEE  REPLACEMENT  ) 

    HINT:

    Steering lock ECU is provided with the steering lock actuator.

    NG: Go to next step 

  2. INSPECT UNLOCK WARNING SWITCH ASSY 
    1. Disconnect the U7 connector from the unlock warning switch.
    2. Measure the resistance according to the value (s) in the table below.
    UNLOCK WARNING SWITCH ASSY RESISTANCE

    Tester connection Condition Specified condition
    U7-2 - U7-4 Smart key is not inserted 10 kΩ or higher
    U7-3 - U7-4 Push switch is OFF 10 kΩ or higher
    U7-2 - U7-4 Smart key is inserted Below 1 Ω
    U7-3 - U7-4 Push switch is ON Below 1 Ω
    Fig 1: Identifying Terminals Of U7 Unlock Warning Switch Connector
    G03004067Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE UNLOCK WARNING SWITCH ASSY (SEE  REPLACEMENT  ) 

    HINT:

    Unlock warning switch assy is provided with the starter switch.

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU - BODY GROUND) 
    1. Disconnect the S46 connector from the steering lock ECU.
    2. Disconnect the U7 connector from the unlock warning switch.
    3. Measure the resistance according to the value (s) in the table below.
    STEERING LOCK ECU - BODY GROUND RESISTANCE

    Tester connection (Symbols) Condition Specified condition
    S46-11 (PUSH) - U7-3 Always Below 1 Ω
    S46-11 (PUSH) -Body ground Always 10 kΩ or higher
    S46-12 (KSW) - U7-2 Always Below 1 Ω
    S46-12 (KSW) - Body ground Always 10 kΩ or higher
    S46-9 (GND) - Body ground Always Below 1 Ω
    U7-4 - Body ground Always Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 2: Checking Harness And Connector (Steering Lock ECU - Body Ground)
    G03004068Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE STEERING LOCK ECU (SEE  REPLACEMENT  ) 

    HINT:

    Steering lock ECU is provided with the steering lock actuator.

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