ELECTRONICALLY CONTROLLED BRAKE SYSTEM FAIL-SAFE CHART


  1. FAIL-SAFE OPERATION


    • When trouble occurs in the brake control system, the skid control ECU turns the warning lights on, displays a DTC corresponding to the malfunctioning systems on the multi-information display, and prohibits ABS, BA, TR(A)C 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.

    Tech Tips


    • If control of the electronically controlled brake system 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 brake stroke simulator cylinder (pedal reactive force generating solenoid) operation will be prohibited.

    • If control of the electronically controlled brake system for all wheels is prohibited, the 2 front wheels will lose brake booster function.

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

    Hybrid control system

    (TR(A)C and VSC systems)

    Before control: Disables control

    During control: Uses only the brakes to effect control

    Brake control system

    (TR(A)C and VSC systems)

    Before control: Disables control

    During control: Disables control (by gradually ending control)

    Tech Tips

    As for the TR(A)C and VSC systems, different systems prohibit different controls depending on a malfunctioning part.