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Fail-Safe Chart

  1. FAIL SAFE OPERATION 
    • When trouble occurs in the brake control system, the skid control ECU comes on the warning light on, displays a DTC corresponding to the malfunctioning systems on the multi information display, and prohibits ABS, BA, and VSC operations.
    • The skid control ECU prevents operation of a malfunctioning hydraulic pressure system and continues brake control with the normal hydraulic pressure system.

    HINT:

    • If control of the ECB for any of the 4 wheels is prohibited, that wheel loses brake booster function or braking ability.
    • If one of the 4 wheels loses brake booster function, the feeling when depressing the brake pedal changes as the stroke simulator (pedal reactive force generating solenoid) operation will be prohibited.
    • If control of the ECB for all wheels is prohibited, the 2 front wheels will lose brake booster function.

    ABS, EBD and BA system: 

    MALFUNCTION AREA AND CONTROL METHOD

    Malfunction Area Control Method
    ABS system ABS, BA, TRAC and VSC control prohibited
    BA system ABS, BA, TRAC and VSC control prohibited
    EBD system ABS, EBD, BA, TRAC and VSC control prohibited

    HINT:

    A malfunction in either the ABS or BA system will result in an identical operation, with ABS, BA, TRAC and VSC system control prohibited.

    TRAC and VSC system: 

    MALFUNCTION AREA AND CONTROL METHOD

    Malfunction Area Control Method
    Engine control system (TRAC and VSC systems) Before control: Disables control
    During control: Uses only the brakes to effect control
    Brake control system (TRAC and VSC systems) Before control: Disables control
    During control: Disables control (by gradually ending control)

    HINT:

    As for the TRAC and VSC systems, different systems prohibit different controls depending on a malfunctioning part.