SsangYong Rodius (2013 year). Manual — part 169

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4891-01

Brake Pressure Sensor, ESP Sensor, Sensor Cluster, ESP OFF Switch

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4891-01

1. SYSTEM OVERVIEW

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.

1) Basic Theory of ABS Function

To give you a better understanding of the tasks and functions of ABS, we will first look at the physics

principles.

▶Stopping distance

The stopping distance depends on the vehicle weight and initial speed when braking starts. This also

applies for vehicle with ABS, where ABS always tries to set an optimum brake force on each wheel. As

great forces are exerted between the tires and the carriageway when braking, even with ABS the

wheels may scream and rubber is left on the road. With an ABS skid mark one may be able to clearly

recognize the tire profile. The skid mark of an ABS vehicle does not however leave any hint of the

speed of the vehicle in the case of an accident, as it can only be clearly drawn at the start of braking.

▶Brake force on a wheel

The maximum possible brake force on a wheel depends on the wheel load and the adhesion

coefficient between tire and carriageway. With a low adhesion coefficient the brake force, which can be

obtained is very low. You are bound to know the result already from driving on winter roads. With a

high adhesion coefficient on a dry road, the brake force, which can be obtained, is considerably higher.

The brake force, which can be obtained, can be calculated from below formula:

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2) Maximum Brake Force

FBmax = wheel load FR x coefficient of friction (Mh)

The braking process cannot be described

sufficiently accurately with the brake forces

calculated. The values calculated only apply if

the wheel is not locked. In the case of a locking

wheel, the static friction turns into lower sliding

friction, with the result that the stopping distance

is increased. This loss of friction is termed "slip"

in specialist literature.

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Warning Lamps

EBD warning lamp

ABS warning lamp

2. COMPONENTS AND LAYOUT

The basic functions of ABS system are same with previous version. However, the wheel speed

sensing type is different from previous version.

For details about the components,

refer to Chapter "ESP".

Front Active Wheel Speed Sensor

4WD

2WD

ABS HECU

Rear Active Wheel

Speed Sensor