GENERAL INFORMATION

OUTLINE OF CHANGE

Associated with the change from the Anti-lock Brake System (ABS) to the Active Stability Control (ASC) system, the general information and maintenance procedure have been added. For other maintenance guidelines, refer to the conventional ABS. <Vehicles for GCC>

TECHNICAL FEATURES

An ASC system incorporates a Traction Control (TCL) function and a stability control function. This system have the following features.

note

The ASC has the TCL function and the stability control function. By the integrated control with the ABS, the system stabilises the vehicle attitude and at the same time secures the driving force.

When the TCL function detects the slip of driving wheel (eg. during startup on slippery road), it automatically applies the braking force to the slipping driving wheel. At the same time, TCL function reduces the engine output and prevents the wheel spin when it determines that the engine torque is too high for the road surface friction coefficient.
When the stability control function determines that the vehicle is in a critical state, it reduces the engine output and applies brake force to four wheels independently to control the vehicle behaviour, avoiding the critical state.
Ensuring braking performance and improvement in service quality by fail-safe function during ASC system malfunction
The Brake Assist (BA) control determines an emergency braking and increases the braking force for the drivers who cannot depress the brake sufficiently when the emergency brake is applied. This shortens the distance to stop or reduces the collision speed.
A Hill Start Assist (HSA) will prevent the vehicle from moving backwards during uphill starting.

CONSTRUCTION DIAGRAM

MAIN COMPONENTS AND FUNCTIONS

Name of part		Number	Functional description
Sensor	Wheel speed sensor	1	Outputs the frequency signal in proportion to the rotation speed of each wheel to ASC-ECU.
	Magnetic encoder for wheel speed detection	2	The wheel speed sensor is a pulse generator. When the magnetic encoder for wheel speed detection (a plate on which north and south pole sides of the magnets are arranged alternately) rotates, it outputs frequency pulse signal in proportion to each wheel speed.
	Stop lamp switch	3	Outputs the signal indicating whether the brake pedal is depressed or not to ASC-ECU.
	G and yaw rate sensor	4	Is integrated in the ASC-ECU, detects the yaw rate and longitudinal and lateral acceleration of a vehicle, and sends a signal to the ASC-ECU.
	Steering wheel sensor	5	Detects the steering angle of the steering wheel, and outputs signal to ASC-ECU via the CAN bus line.
	Brake fluid pressure sensor	6	Integrated into the hydraulic unit, and outputs the signal for the brake fluid pressure in the master cylinder to ASC-ECU.
	ASC OFF switch	7	Sends the reverse gear signal to the ASC-ECU.
Actuator	Hydraulic unit	8	Drives the solenoid valve using the signal from ASC-ECU, and controls the brake fluid pressure for each wheel.
	Combination meter	9	Activates the warning lamp and the indicator lamp to inform the driver of a current system status.
	Combination meter	9	Informs the ASC-ECU how the parking brake works.
Diagnosis connector		10	Communicates with M.U.T.-III, such as output of a diagnosis code.
Engine-ECU		11	Controls the engine output based on the signal from ASC-ECU.
CVT-ECU		12	CVT-ECU performs integrated control with ASC-ECU. Output the gear position to ASC-ECU.
ETACS-ECU		13	Relays a signal from the stop lamp switch and the back up lamp switch to the ASC-ECU.
ASC control unit (ASC-ECU)		14	Controls the actuators (hydraulic unit) based on the signals sent from sensors.
			Controls the self-diagnostic function and fail-safe function.
			Controls diagnostic function (Compatible with M.U.T.-III).

System Configuration

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Dashed lines indicate the CAN bus line.