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Fail-Safe Chart

  1. FAIL SAFE OPERATION 
    • If there is a problem with sensor signals or brake actuator systems, the skid control ECU prohibits power supply to the brake actuator and informs the ECM of VSC system failure.

      The brake actuator turns off the solenoids and the ECM stops its VSC according to signals from the skid control ECU. The vehicle will operate in a manner similar to a vehicle that is not equipped with ABS, TR(A)C and VSC systems.

      ABS control will be prohibited, but EBD control will continue to the extent that EBD control is possible. If EBD control is impossible, the brake warning light will come on to warn the driver. Refer to DIAGNOSIS SYSTEM .

    • If a VSC system component malfunctions before VSC begins, VSC will be prohibited. If a system component malfunctions while VSC is operating, the system will gradually stop operating so as not to trigger a sudden change in vehicle stability.

      If it is impossible to control the systems, the warning light will come on to inform the driver of system control termination. Refer to DIAGNOSIS SYSTEM .

      HINT: 

      For vehicles with the multi-information display, the master warning light will come on and a warning message will be displayed on the multi-information display if any of the EBD system, BA system, or TR(A)C system is malfunctioning or if the ABS control or VSC cannot be performed.

    ABS, EBD AND BA SYSTEM

    Malfunctioning Area Control Method
    ABS system ABS, BA, TR(A)C, VSC control prohibited
    BA system ABS, BA, TR(A)C, VSC control prohibited
    EBD system ABS, EBD, BA, TR(A)C, VSC control prohibited

    HINT: 

    A malfunction in either the ABS or BA system will result in identical operation, with ABS, BA, TR(A)C, VSC system control being prohibited.

    TR(A)C AND VSC SYSTEM

    Malfunctioning Area Control Method
    Engine control system
    (TR(A)C and VSC systems)
    Before control: Disables control
    During control: Uses only the brakes to perform control
    Brake control system
    (VSC system)
    Before control: Disables control
    During control: Uses only the engine to perform control
    Brake control system
    (TR(A)C system)
    Before control: Disables control
    During control: Disables control (by gradually stopping control)

    HINT: 

    The TR(A)C and VSC systems use different systems to prohibit different controls depending on the malfunctioning parts.