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DTC B2284: Brake Signal Malfunction: Procedure

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

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (AUXILIARY BATTERY - POWER MANAGEMENT CONTROL ECU) 

    OK: Go to next step 

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

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER MANAGEMENT CONTROL ECU - BODY GROUND) 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - POWER SOURCE AND BODY GROUND) 
    1. Disconnect the A67 connector from the stop light switch assembly.
      Fig 1: Identifying A67 Stop Light Switch Assembly Connector Terminal
      GTY336359Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A67-1 (B) - A67-3 (GND) Always 11 to 14 V

      Standard Resistance

      Tester Connection Condition Specified Condition
      A67-3 (GND) - Body ground Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Stop Light Switch Assembly)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  4. CHECK STOP LIGHT SWITCH ASSEMBLY 
    1. Reconnect the A67 connector to the stop light switch assembly.
      Fig 2: Identifying A67 Stop Light Switch Assembly Connector Terminal
      GTY325145Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A67-2 (L) - A67-3 (GND) Power switch off, brake pedal not depressed Below 1 V
      A67-2 (L) - A67-3 (GND) Power switch off, brake pedal depressed 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Stop Light Switch Assembly)

    NG → REPLACE STOP LIGHT SWITCH ASSEMBLY 

    OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - POWER MANAGEMENT CONTROL ECU) 
    1. Disconnect the A22 connector from the power management control ECU.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A22-23 (STP) - A67-2 (L) Always Below 1 Ω
      A22-23 (STP) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - POWER MANAGEMENT CONTROL ECU) 

    OK: Go to next step 

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

      Tester Display Measurement Item/Range Normal Condition Specified Condition
      Stop Light Switch1 Stop light switch1/ON or OFF ON: Brake pedal depressed
      OFF: Brake pedal released
      -

      OK

      ON (brake pedal is depressed) and OFF (brake pedal is released) appear on the screen.

    NG → See step   7 

    OK → See step   8 

  7. REPLACE POWER MANAGEMENT CONTROL ECU. Refer to  REMOVAL 
  8. GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM (DTC C1249/49). Refer to  HOW TO PROCEED WITH TROUBLESHOOTING