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Home >> Toyota >> 2021 >> Corolla SE Apex >> Repair and Diagnosis >> External Pages >> Different car >> Section 10 (Electronically Controlled Brake System (Except HEV) (W/O Electric Parking Brake) (TMC) - Diagnostic Codes, Symptom Tests & Circuit Tests) >> ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for Gasoline Model without Electric Parking Brake System TMC Made) >> VSC OFF Switch Circuit [09/2022 - 09/2024] >> Procedure

VSC OFF Switch Circuit [09/2022 - 09/2024]: Procedure

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  1. READ VALUE USING GTS (TRAC/VSC OFF MODE) 
    1. Check that the indicator light and mode condition on the GTS change according to VSC OFF switch (combination switch assembly) operation.

      Chassis > Brake/EPB > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      TRC (TRAC)/VSC OFF Mode TRAC/VSC off mode Normal mode (TRC (TRAC) ON/VSC ON) / TRC (TRAC) OFF mode (TRC (TRAC) OFF/VSC ON) / VSC expert mode (VSC expert mode MID ON) / VSC OFF mode (TRC (TRAC) OFF/VSC OFF) Normal mode (TRC (TRAC) ON/VSC ON): Normal mode
      TRC (TRAC) OFF mode (TRC (TRAC) OFF/VSC ON): TRAC off mode
      VSC expert mode (VSC expert mode MID ON): VSC expert mode
      VSC OFF mode (TRC (TRAC) OFF/VSC OFF): VSC off mode
      -

      Chassis > Brake/EPB > Data List 

      Tester Display
      TRC (TRAC)/VSC OFF Mode

      Standard

      Switch Operation Mode Condition Display TRAC OFF Indicator Light VSC OFF Indicator Light
      Not pressed Normal mode (TRC (TRAC) ON/VSC ON) Does not come on Does not come on
      Pressing the VSC OFF switch (combination switch assembly) TRC (TRAC) OFF mode (TRC (TRAC) OFF/VSC ON) Comes on Does not come on
      Pressing and holding the VSC OFF switch (combination switch assembly) VSC OFF mode (TRC (TRAC) OFF/VSC OFF) Comes on Comes on

      Result

      Result Proceed to
      Indicator light and mode condition display do not change. A
      Mode condition display is normal, but indicator light does not change. B
      Indicator light and mode condition display are normal. C

    Result: 

    INSPECT METER / GAUGE SYSTEM 

    Refer to HOW TO PROCEED WITH TROUBLESHOOTING [09/2022 - 11/2022] , or refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2022 - ]

    Result: 

    USE SIMULATION METHOD TO CHECK 

    Refer to HOW TO PROCEED WITH TROUBLESHOOTING [06/2018 - ]

    Result: 

    See step  2

  2. INSPECT COMBINATION SWITCH ASSEMBLY 
    1. Turn the ignition switch off.
    2. Inspect the VSC OFF switch (combination switch assembly).

      Refer to INSPECTION [09/2022 - ]

      OK

      The VSC OFF switch (combination switch assembly) is normal.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE COMBINATION SWITCH ASSEMBLY 

    Refer to REMOVAL [09/2022 - 11/2022] , or refer to REMOVAL [11/2022 - 09/2024]

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY - COMBINATION SWITCH ASSEMBLY) 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connectors.

      OK

      The connector is securely connected.

    2. Disconnect the A140 skid control ECU (brake actuator assembly) connector.
    3. Check both the connector case and the terminals for deformation and corrosion.

      OK

      No deformation or corrosion.

    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A140-9 (CSW) - I177-8 (+) Always Below 1 Ω
      A140-9 (CSW) or I177-8 (+) - Body ground Always 10 kΩ or higher
      I177-5 (E) - Body ground 1 minute or more after disconnecting the cable from the negative (-) battery terminal Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE BRAKE ACTUATOR ASSEMBLY 

    Refer to REMOVAL [09/2022 - 11/2022] , or refer to REMOVAL [11/2022 - 09/2024]

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR