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DTC B2284: Brake Signal Malfunction [08/2015 - 08/2019]: Procedure

  1. CHECK HARNESS AND CONNECTOR (BATTERY - POWER MANAGEMENT CONTROL ECU) 

    See step  1

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - BODY GROUND) 

    See step  2

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. INSPECT STOP LIGHT SWITCH ASSEMBLY 
    1. Inspect the stop light switch assembly (Refer to ON-VEHICLE INSPECTION [08/2015 - 08/2019] ).

    Result: 

    NG 

    REPLACE STOP LIGHT SWITCH ASSEMBLY 

    (Refer to REMOVAL [08/2015 - ] )

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - STOP LIGHT SWITCH ASSEMBLY) 
    1. Disconnect the F81 power management control ECU connector.
    2. Disconnect the A47 stop light switch assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F81-11 (STP1) - A47-3 (L) Always Below 1 Ω
      F81-11 (STP1) - Body ground Always 10 kΩ or higher
    4. Reconnect the A47 stop light switch assembly connector.
      GTY714852Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      F81-11 (STP1) - Body ground Brake pedal not depressed Below 1 V
      Brake pedal depressed ([Voltage at terminal AM21 or AM22] minus 2.0 V) or higher
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Power Management Control ECU)

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Power Source Control / Data List.
    5. According to the display on the Techstream, read the Data List.
      POWER SOURCE CONTROL

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Stop Light Switch1 Stop light switch 1 / ON or OFF ON: Brake pedal depressed
      OFF: Brake pedal released
      -

      OK

      ON (brake pedal depressed) or OFF (brake pedal released) appears on the screen according to the stop light switch condition.

    Result: 

    OK 

    REPLACE POWER MANAGEMENT CONTROL ECU 

    (Refer to REMOVAL [08/2015 - 08/2019] )

    Result: 

    NG 

    GO TO SFI SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) 

    (Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - ] )