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DTC B2284: Brake Signal Correlation [11/2021 - ]: Procedure

  1. CHECK CAN COMMUNICATION SYSTEM 
    1. Perform the diagnosis for CAN communication system.

      Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2021 - ]

      Is the check result OK?

      Result Proceed to
      Yes A
      No (Perform the inspection according to the diagnosis for CAN communication system.) B

    Result: 

    B 

    PERFORM THE INSPECTION ACCORDING TO THE DIAGNOSIS FOR CAN COMMUNICATION SYSTEM 

    Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2021 - ]

    Result: 

    A 

    See step  2

  2. CHECK DATA MONITOR 
    1. Turn the ignition switch to ON.
    2. Using the GTS, check the following items in the [Data Monitor] of [Keyless Access with Push Button Start(Power Supply)].

      Refer to DATA LIST / ACTIVE TEST [11/2021 - ]

      • Stop lamp SW

      Does the display change correctly according to the brake pedal operation?

      Result Proceed to
      Yes A
      No (Check the stop light system.) B

    Result: 

    B 

    CHECK STOP LIGHT SWITCH ASSEMBLY 

    Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2021 - ]

    Result: 

    A 

    See step  3

  3. CHECK DATA MONITOR 
    1. Using the GTS, check the following items in the [Data Monitor] of [Body Control].

      Refer to DATA LIST / ACTIVE TEST [11/2021 - 10/2024] , or refer to DATA LIST / ACTIVE TEST [10/2024 - ]

      • Stop Light Switch

      Does the display change correctly according to the brake pedal operation?

      Result Proceed to
      Yes A
      No (Check main body (multiplex network body ECU). And check the stop light switch circuit.) B

    Result: 

    B 

    CHECK MAIN BODY (MULTIPLEX NETWORK BODY ECU) 

    1. Check main body (multiplex network body ECU).

      Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2021 - ]

    2. And check the stop light switch circuit.

      Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2021 - ]

    Result: 

    A 

    See step  4

  4. CHECK FUSE 
    1. Turn the ignition switch to OFF.
    2. Check the fuse.

      Is the check result OK?

      Result Proceed to
      Yes A
      No (Replace the fuse. When the replaced fuse is blown immediately, check the power supply circuit for short circuited.) B

    Result: 

    B 

    REPLACE FUSE 

    1. Replace the fuse.
    2. When the replaced fuse is blown immediately, check the power supply circuit for short circuited.

    Result: 

    A 

    See step  5

  5. CHECK HARNESS 
    1. Disconnect the connector from the smart key ECU assembly.
    2. Turn the ignition switch to ON.
    3. Using a tester, measure the voltage between the smart key ECU assembly connector and chassis ground.

      Connector & terminal

      F8-1 (+B2) (+) - Chassis ground (-)

      F8-4 (+B1) (+) - Chassis ground (-)

      Is the voltage 9.5 - 16 V?

      Result Proceed to
      Yes A
      No (Check the power supply circuit.) B

    Result: 

    B 

    CHECK THE POWER SUPPLY CIRCUIT 

    Result: 

    A 

    See step  6

  6. CHECK HARNESS (OPEN CIRCUIT) 
    1. Turn the ignition switch to OFF.
    2. Using a tester, measure the resistance between the smart key ECU assembly connector and chassis ground.

      Connector & terminal

      F9-17 (GND2) - Chassis ground

      F8-20 (GND1) - Chassis ground

      Is the resistance less than 1 Ω?

      Result Proceed to
      Yes A
      No (Repair or replace the open circuit of harness.) B

    Result: 

    B 

    REPAIR OR REPLACE THE OPEN CIRCUIT OF HARNESS 

    Result: 

    A 

    See step  7

  7. CHECK HARNESS (OPEN CIRCUIT) 
    1. Disconnect the connector from stop light switch.
    2. Using a tester, measure the resistance between the smart key ECU assembly connector and stop light switch connector.

      Connector & terminal

      F9-27 (STP1) - A23-2

      Is the resistance less than 1 Ω?

      Result Proceed to
      Yes A
      No (Repair or replace the open circuit of harness.) B

    Result: 

    B 

    REPAIR OR REPLACE THE OPEN CIRCUIT OF HARNESS 

    Result: 

    A 

    See step  8

  8. CHECK HARNESS (GROUND SHORT CIRCUIT) 
    1. Using a tester, measure the resistance between the smart key ECU assembly connector and chassis ground.

      Connector & terminal

      F9-27 (STP1) - Chassis ground

      Is the resistance 10 kΩ or more?

      Result Proceed to
      Yes A
      No (Repair or replace the short circuit of the harness.) B

    Result: 

    B 

    REPAIR OR REPLACE THE SHORT CIRCUIT OF THE HARNESS 

    Result: 

    A 

    See step  9

  9. CHECK HARNESS 
    1. Connect the disconnected connectors.
    2. Turn the ignition switch to ON.
    3. Using a tester, measure the voltage between the smart key ECU assembly connector and chassis ground when the brake pedal is depressed.

      Connector & terminal

      F9-27 (STP1) (+) - Chassis ground (-)

      Does the voltage change as follows? Brake pedal not depressed: voltage of 1 V or less → Brake pedal depressed: voltage of 11 - 14 V

      Result Proceed to
      Yes (Replace the smart key ECU assembly.) A
      No (Check the power supply circuit of stop light switch.) B

    Result: 

    A 

    REPLACE SMART KEY ECU ASSEMBLY 

    Refer to REMOVAL [11/2021 - ]

    Result: 

    B 

    CHECK THE POWER SUPPLY CIRCUIT OF STOP LIGHT SWITCH 

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