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Inspection Procedure

  1. INSPECT FUSE (MPX-B1, AM2) 
    1. Remove the MPX-B1 fuse and AM2 fuse from the passenger side J/B.
    2. Check for continuity of the fuses.

    Standard: Continuity 

    NG: INSPECT FOR SHORT IN ALL COMPONENTS CONNECTED TO FUSE AND REPAIR OR REPLACE THEM IF NEEDED, AND REPLACE FUSE 

    Fig 1: Identifying Location Of MPX-B1 And AM2 Fuses
    G03004073Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  2. INSPECT STEERING LOCK ECU (CPUB, IG2 TERMINAL VOLTAGE) 
    1. Disconnect the S46 connector from the steering lock ECU.
    2. Measure the voltage according to the value (s) in the table below.
    STEERING LOCK ECU (CPUB, IG2 TERMINAL VOLTAGE)

    Tester connection (Symbols) Condition Specified condition
    S46-1 - S46-9 (CPUB - GND) Always 10 to 14V
    S46-2 - S46-9 (IG2 - GND) Ignition switch is in ON position 10 to 14V

    OK: REPLACE STEERING LOCK ECU (SEE  REPLACEMENT  ) 

    HINT:

    Steering lock ECU is provided with the steering lock actuator.

    Fig 2: Inspecting Steering Lock ECU (CPUB, IG2 Terminal Voltage)
    G03004074Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: 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. Measure the resistance according to the value (s) in the table below.
    STEERING LOCK ECU - BODY GROUND RESISTANCE

    Tester connection (Symbols) Condition Specified condition
    S46-9 - (GND) -Body ground Always Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STEERING LOCK ECU - BODY GROUND) 

    Fig 3: Checking Harness And Connector (Steering Lock ECU - Body Ground)
    G03004075Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (STEERING LOCK ECU - BATTERY)