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Inspection Procedure

  1. CHECK PARKING BRAKE (DISPLAY CHECK MODE) 
    1. Enter the "Display Check" mode and select "Vehicle Signal Check" (See OPERATION CHECK  ).
    2. Check that the display changes between ON and OFF according to the parking brake operation.

      OK 

      PARKING BRAKE POSITION REFERENCE

      Parking Brake Position Display
      Applied ON
      Released OFF
      Fig 1: Diagnosis Display - Vehicle Signal Check Mode Screen
      G05763413Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

      This display is updated once per second. As a result, it is normal for the display to lag behind the actual change in the switch.

    NG: Go to step 2 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE  (See PROBLEM SYMPTOMS TABLE  )

  2. CHECK MAIN BODY ECU (PARKING BRAKE SIGNAL) 
    1. Disconnect the F28 display connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      F28-23 (PKB) - Body ground Engine switch on (IG), parking brake applied 11 to 14 V
      F28-23 (PKB) - Body ground Engine switch on (IG), parking brake released Below 1 V

    NG: Go to step 3 

    Fig 2: Identifying Display And Navigation Module Display Connector Terminal
    G05763414Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE DISPLAY AND NAVIGATION MODULE DISPLAY  (See REMOVAL  )

  3. CHECK HARNESS AND CONNECTOR (DISPLAY AND NAVIGATION MODULE DISPLAY MAIN BODY ECU) 
    1. Disconnect the F28 display connector.
    2. Disconnect the 2E ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      F28-23 (PKB) - 2E-2 (PKB) Always Below 1 Ω
      F28-23 (PKB) - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 3: Identifying Display And Navigation Module Display And Main Body ECU Connector Terminals
    G05763415Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  4. REPLACE MAIN BODY ECU 
    1. Temporarily replace the ECU with a new or normally functioning one.
    2. Check that the parking brake signal is displayed on the multi-display.

      OK: Parking brake signal is displayed on the multi-display. 

    NG: REPLACE DISPLAY AND NAVIGATION MODULE DISPLAY  (See REMOVAL  )

    OK: END (MAIN BODY ECU IS DEFECTIVE) 

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