SsangYong Rodius (2013 year). Service manual — part 167

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4. SCHEMATIC DIAGRAM

When equipped with ABS, the braking force at each wheel will be controlled with 3-channel 4-sensor

method. And when equipped with ESP, 4 wheels will be controlled independently with 4-channel

method. (When controlling ABS system only, it will be operated with 3-channel method.) 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 increase, decrease or unchanged conditions.

▶The warning lamp comes on and warning beep sounds when the ESP is operating

Driving feeling when the ESP is operating

▶

▶Noise and vibration that driver senses when the ESP is operating

1) Hydraulic Circuit Diagram

When the ESP operates during vehicle movement, the ESP warning lamp on the instrument panel

flickers and beep comes on every 0.1 second. The ESP operation shows that the vehicle stability is

extremely unstable and it is used to warn the driver. The ESP system is just a supplementary system

for the vehicle motion and it cannot control the vehicle when it exceeds the physical limits. Do not

solely rely on the system but be advised to drive the vehicle safely.

When the ESP system activates, the driving feeling can be different depending on vehicle driving

conditions. For example, you will feel differently when the ESP system is activated during when ABS

is operating with the brakes applied and when brakes are not applied on a curve. Thus, the ESP

system would make the driver feel more abruptly when the brakes are applied during the ESP

system activation.

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. Extreme cornering will trigger the

ESP operation and this will make the driver feel noise and vibration due to sudden brake application.

Also, the ESP system controls the engine output. So, the driver may notice the engine output

decrease even when the accelerator pedal is being applied.

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(1) Hydraulic Circuit Diagram

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.

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(2) Hydraulic Circuit of HBA

The above figure shows one front and one rear wheel and the same hydraulic circuit forms as in the

ESP operation. When HECU recognizes that it is an emergency and it is required for hard braking,

depending on the pressure value of the brake pressure sensor and pressure changes caused by the

pressure sensor timing, it operates the pump immediately to apply the brake pressure at the wheels.

Then, the pressure in the pump increases until just before the corresponding wheel gets locked. The

motor still keeps rotating and the outlet valve and the separation valve will stay closed. When the wheel

starts to lock, the HBA function cancels and switches to ABS operation.

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(3) Hydraulic Circuit Diagrams in Conditions

▶Idling and Normal Braking Condition

In this position, the separation valve and the inlet valve are open (normal open), the electrically

operated shuttle valve and the outlet valve are closed.

When the brake is applied under these conditions, the brake fluid will be sent to each wheel via the

separation valve and inlet valve.