Vehicle Stability Control System (For Vacuum Brake Booster) Fail-Safe Chart

  1. FAIL-SAFE OPERATION

Vehicle Stability Control System (For Vacuum Brake Booster) -- Fail-Safe Chart



FAIL-SAFE OPERATION
  1. If there is a problem with sensor signals or brake actuator systems, the skid control ECU prohibits power from being supplied to the brake actuator assembly and informs the ECM of VSC system failure.
    The brake actuator assembly turns off each solenoid and the ECM stops its VSC (traction control signal), which is based on signals from the skid control ECU. As a result, it is if the ABS, TRC and VSC systems were not installed.
    ABS control is prohibited, but EBD control continues to the extent that it is possible. If EBD control is impossible, the brake warning light comes on to warn the driver (LandCruiser RM000000XHP0JRX.html).
  2. If a system component has any malfunction before control begins, operation is prohibited. If a system component has any malfunction during control, the system will gradually stop operating so as not to trigger a sudden change in vehicle conditions.
    If it is impossible to control the systems, the warning light comes on to inform the driver of termination of control of the systems (LandCruiser RM000000XHP0JRX.html).
HINT:
If the brake booster encounters a malfunction, brake performance is gradually lost and ABS, BA, TRC and VSC systems are prohibited.

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

TRC and VSC Systems
Malfunction Area
Control Method
Engine control system
(TRC 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 engine to perform control
Brake control system
(TRC system)
Before control: Disables control
During control: Disables control (by gradually ending control)
HINT:
As for the TRC and VSC systems, different systems prohibit different controls depending on the malfunctioning part.