2012 SSANGYONG KORANDO brakes

03-113660-01
1. OVERVIEW
2WD4WD
The Model 6F24 6 speed automatic transaxle is electronically controlled. The control system is
comprised of the following components:
External transaxle control unit (TCU)
Input and output speed sensors
Six variable force solenoids(VFS) and two on/off solenoids
Torque converter
ATF temperature sensor -
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TCU controls the oil pressure for various internal clutches and brakes to select the gear. It also controls
the electronic elements, shift pressure and torque converter slip. If the system is defective, TCU provides
FMEC (Failure Mode Effect Control) to maintain the functionality of transaxle. This keeps the basic
function of transaxle (gear selection) even when there are failure in controls and power supply.
There are selector shaft position sensor (inhibitor switch) and oil temperature sensor in transaxle. In
manual mode, TCU receives the information from TGS (Transmission Gear Selector) through PCB
(Printed Circuit Board) when driver selects the manual shift mode. TCU communicates with other electric
control modules through CAN. In order to ensure a safe driving state and to prevent damage to the
automatic transmission, TCU switches to Limp-Home mode in the event of critical faults.

10-54890-00
1. SYSTEM OVERVIEW
1) What is ABS?
When braking suddenly or braking on slippery roads, the vehicle keeps moving forward but the wheels
are locking and not rotating. If these happen, the vehicle may lose stability or rotate resulting in an
accident. ABS helps to maintain directional stability and control of the vehicle. ABS is designed to
secure more safety and increase the control of steering wheel during emergency braking situation. But,
ABS does not guarantee perfect safety beyond its physical limit. ABS in this vehicle contains EBD
function. In normal driving conditions, the brake system operates without ABS function.
2) What is EBD (Electronic Brake-force Distribution)?
EBD is an automobile brake technology that automatically varies the amount of force applied to each of a
vehicle's brakes, based on road conditions, speed, loading, etc. Always coupled with anti-lock braking
systems, EBD can apply more or less braking pressure to each wheel in order to maximize stopping
power whilst maintaining vehicular control. EBD does not operate when ABS is working.ABS effect according to braking conditions ▶
Braking on split road Maneuvering while braking

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5) EBD (Electronic Brake Force Distribution) System
System description ▶
As an add-on logic to the ABS base algorithm, EBD works in a range in which the intervention
thresholds for ABS control are not reached yet.
EBD ensures that the rear wheels are sensitively monitored for slip with respect to the front axle. If slip is
detected, the inlet valves for the rear wheels are switched to pressure hold to prevent a further increase
in pressure at the rear-wheel breaks, thus electronically reproducing
a pressure-reduction function at the rear-wheel brakes.
ABS features an enhanced algorithm which includes control of the brake force distribution between the
front and rear axles. This is called Electronic Brake Distribution. In an unloading car condition the brake
efficiency is comparable to the conventional system but for a fully loaded vehicle the efficiency of the
EBD system is higher due to the better use of rear axle braking capability.
Advantages ▶
Elimination of conventional proportioning valve
EBD utilizes the existing rear axle wheel speed
sensor to monitor rear wheel slip.
Based on many variables in algorithm a
pressure hold, increase and/or decrease
pulsetrain may be triggered at the rear wheels
insuring vehicle stability.
Vehicle approaches the ideal brake force
distribution (front to rear).
Constant brake force distribution during vehicle
lifetime.
EBD function is monitored via ABS safety logic
(conventional proportioning valves are not
monitorable). -
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3. PRECAUTIONS
The warning lamp flashes and warning beep sounds when the ESP is operating
When the ESP operates during vehicle movement, the ESP warning lamp on the instrument panel
flashes and beep comes on every 0.1 second. The ESP system is only a supplementary device for
comfortable driving. When the vehicle exceeds its physical limits, it cannot be controlled.
Do not rely on the system. Keep on the safe driving.
Feeling when ESP is working
When the ESP system activates, the feeling can be different depending on vehicle driving conditions.
For example, you will feel differently when the ESP system is activated during the ABS is operating
with the brakes applied and when the brakes are not applied on a curve.
If the ESP system operates when the brake is applied, the brake pressure will be increased on the
corresponding wheel which already has braking pressure for the ESP controls.
ARP Operation
During the ARP operation, vehicle safety (rollover prevention) takes the first priority and thus,
stronger engine control is in effect. Consequently, the vehicle speed decreases rapidly, so the driver
must take caution for the vehicle may drift away from the lane.
Noise and vibration that driver feels when ESP system is operating
The ESP system may transfer noise and vibration to the driver due to the pressure changes caused
by the motor and valve operations in a very short period of time. And, keep in mind that the output
and vehicle speed could be decreased without rpm increase due to the ASR function that controls
the engine power.

11-16
5) ARP (Active Roll-Over Protection)
The ARP (Active Roll-over Protection) system is a safety assistant device that minimizes, by controlling
brakes and the engine, the physical tendency of the vehicle rollover during sharp lane changes or U-
turns. For the system, software is added to the existing ESP system and no additional device or switch is
needed. One must note that the ARP system, just as general assistant devices including the ABS, is only
a safety assistant device using the ESP system and its function is useless when the situation overcomes
the physical power. Following picture shows how the ARP compensates the vehicle position by varying
each wheel's braking power to overcome the physical tendency of the vehicle rollover during sharp turns.
Lateral sensor
(In sensor cluster)
Vehicle speedBrake force
Radius
The vehicle driving condition is controlled by the internally programmed logic according to the input
signals from wheel speed sensor, steering angle sensor and lateral sensor.
During the ARP operation, vehicle safety (rollover prevention) takes the first priority and thus,
stronger engine control is in effect. Consequently, the vehicle speed decreases rapidly, so the driver
must take caution for the vehicle may drift away from the lane.

11-210000-00
Circuit description ▶
When compared to the vehicle equipped with ABS/EBD only, the internal hydraulic circuit has a
normally-open separation valve and a shuttle valve in primary circuit and in secondary circuit.
When the vehicle brakes are not applied during engine running or when applying the non-ABS operating
brakes, the normally-open separation valve and the inlet valve are open, whereas the normally-closed
shuttle valve and the outlet valve are closed.
When the ESP system is operating, the normally-open separation valve will be closed by the solenoid
valve operation and the hydraulic circuit will be established by the shuttle valve. Then, the inlet and outlet
valves will be closed or open depending on the braking pressure RISE, HOLD or DUMP conditions.
Flashing warning lamp and warning sound during ESP operation ▶
When the ESP operates while the vehicle is moving, the ESP warning lamp on the instrument panel
flickers and the buzzer sounds at every 0.1 second. The ESP lamp operation is to inform a driver that the
vehicle is extremely unstable.
The ESP system is just a supplementary system for the vehicle and it cannot control the vehicle over the
physical limit. Do not solely rely on the system but be advised to drive the vehicle safely.
Drive feeling during ESP operation ▶
When the ESP system activates, the driving feeling can be different depending on vehicle driving
conditions. For example, it will feel different when the ESP system is activated while the ABS is operated
by depressing the brake pedal and when the ESP system is in control without the brake pedal
depressed on the same curve.
If the ESP system operates with the brake applied, the brake pressure will be increased on the
corresponding wheel which already has braking pressure for the ESP controls. In other words, the ESP
system would make the driver feel more abruptly braked compared to the situation that the braking
pressure is applied to wheel which had no braking force.
Noise and vibration that driver senses during ESP operation ▶
The ESP system may transfer noise and vibration to a driver due to the pressure changes caused by the
motor and valve operations in a very short period of time.
Extreme cornering will trigger the ESP operation and this will make the driver sense noise and vibration
due to sudden brake application.
Also, the ESP system controls the engine power. Therefore, the driver may notice the engine power
decreases even when the accelerator pedal is depressed.