ABS(Anti-Lock Brake System)

Description

The Anti-Lock Brake System (ABS) controls the hydraulic brake pressure of all four wheels during braking on hazardous road surfaces, preventing the wheels from locking up. ABS provides the following benefits.
1. Enables steering around obstacles with a greater degree of certainty, even during emergency braking.
2. Enables stopping during emergency braking while keeping stability and steerability even on curves.
If a malfunction occurs, a diagnosis function and fail-safe system are included for serviceability.

The Hydraulic and Electronic Control Unit (HECU) receives signals about the vehicle's speed, direction and road conditions from sensors at the wheels.
Based on these signals, the control unit will determine the optimum amount of wheel spin.

WARNING LAMP CONTROL




1. ABS warning lamp module
The active ABS warning lamp module indicates the operating condition of the ABS.

The ABS warning lamp is turned on under the following conditions.
A. During the initialization phase after ignition switch ON (3 seconds).
B. In the event of inhibition of ABS functions by failure.
C. When the system ECU is shut down even though ignition power is applied.
D. During diagnostic mode.
2. EBD warning lamp module
The active EBD warning lamp module indicates the operating condition of the EBD. However, in case the parking brake switch is turned on, the EBD warning lamp is always turned on regardless of EBD functions.

The EBD warning lamp is turned on under the following conditions.
A. During the initialization phase after ignition switch ON. (3 seconds).
B. When the system ECU is shut down even though ignition power is applied.
C. When the parking brake switch is ON or brake fluid is low level.
D. In the event of inhibition of EBD function.
3. TCS warning lamp module
the passive TCS warning lamp module indicates the operating condition of the TCS.

The TCS warning lamp is turned on under the following conditions :
A. During the initialization phase after ignition switch ON (3 seconds).
B. In the event of inhibition of TCS functions by failure.
C. During diagnostic mode.
4. TCS function lamp module
The TCS function lamp indicates the operating condition of TCS function.

The TCS function lamp is on under the following condition
A. During the initialization phase (3seconds).
The TCS function lamp is blinking under the following conditions.
B. During TCS control.

Safety concept
1. ABS
When any failures are occurred in the ABS system, the ABS ECU turns on the warning lamps and inhibits the control corresponding that as follows.





* ) "-" means "Warning Lamp OFF"
2. TCS
When any failures are occurred in the TCS system, the TCS ECU turns on the warning lamps and inhibits the control corresponding that as follows.





* ) "-" means "Warning Lamp OFF"


FUNCTION

1. Main performance
(1) Traction: Lower vibration and higher launchability, acceleration and climbability by slip control.
(2) Cornering and passing: Stable cornering and passing.
(3) Steering stability: Control traction force traverse vector prior to provide easy turning when turning the steering wheel.
2. General TCS features
(1) Improved drivability. Minor operation of acceleration is not necessary in launching and acceleration on slippery read.
(2) More stable cornering by stable acceleration on normal road condition.
(3) TCS system will compare vehicle speed received from rear wheel speed sensor and driving wheel speed from front wheel speed sensor on slippery road condition, and provide optimum slipping rate of driving wheels.

TYPE
FULL TRACTION CONTROL SYSTEM (FTCS)
1. ABS ECM controls TCS control too.
2. ECM will compare signals from front (driving) and rear wheel speed sensors to detect driving wheels slip.
3. Upon detecting driving wheels slip, ECM will perform TCS control. The TCS control will include brake TCS (BTCS) control.
4. ABS ECM will transmit engine torque reduction request, fuel cut cylinder number, and TCS control request signals in accordance with slip level to engine ECM and TCU through BUS line which will provide CAN communication for TCS control.
5. Engine ECM will perform fuel cut as requested by ABS ECM and retard ignition timing as per engine torque reduction request signal.
6. TCU will hold shift position by TCS control time according to TCS operation signal. Then enhanced acceleration by kick-down will not occur.

BRAKE TRACTION CONTROL SYSTEM (BTCS)
1. On TCS control, only brake control will be performed. (engine and TCU control will not happen)
2. Controlled by motor pump output pressure.