2012 SSANGYONG NEW ACTYON SPORTS wheel

10-54892-01
2) ABS System
Sensor - front wheel speed
Sensor - rear wheel speed
Screw (7.8~11.8 Nm)
Clip - cable holder
Clip - sensor cable mounting, rear
Plug - blind
G-sensor
Nut (9.8~10.8 Nm) 1.
2.
3.
4.
5.
6.
9.
11.

10-6
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

10-8
Rear wheel speed sensor (4WD)
Located at both ends of rear axle.
Rear discRear caliper assembly (2WD/4WD)
Located on the knuckle.
ABS warning lampG-sensor
Located on the floor under center
fascia.
2. COMPONENT
EBD warning lamp
(two indicators come on)

10-94892-01
Front wheel speed sensor (4WD)
Located on the hub assembly.
Front discFront caliper assembly (2WD/4WD)
Located on the knuckle.
ABS hydraulic device and control unit
Located near the brake booster in engine compartment.

10-10
3. ABS CONTROL LOGIC
The principal ABS control logic is the determination of the reference speed by choosing one
wheel meeting a certain condition, while sensing the speed information from 4 wheel speed
sensors when the vehicle is being driven.
For example, when the comparison of the reference speed with front right wheel speed shows a
slip, the control signal is determined according to whether it's deceleration or acceleration. If the
control conditions are met, the brake for the front right wheel will be got under control.

10-12
2) EBD (Electronic Brake-force Distribution) Warning Lamp
EBD warning lamps (brake warning lamp and ABS warning lamp) come on when the system
performs the self diagnosis and when it detects the malfunction of EBD system. However, the
brake warning lamp comes on regardless of EBD system when the parking brake is applied.
EBD warning lamp ON:
When turning the ignition switch to ON position, ABS warning lamp and the brake warning
lamp comes on for 3 seconds for self diagnosis and goes off if the system is OK
(initialization mode).
When applying the parking brake, the brake warning lamp comes on.
When the brake fluid is not sufficient, the brake warning lamp comes on.
When disengaging the connector, the warning lamp comes on.
When the system is defective, ABS warning lamp and the brake warning lamp come on
simultaneously. A.
B.
C.
D.
E.
When the solenoid valve is defective
When one or more wheel sensors are defective
When ABS HECU is defective
When the voltage is abnormal
When valve relay is defective a.
b.
c.
d.
e.
When the communication between warning lamp CAN modules in meter cluster is failed,
the warning lamp comes on. F.

10-14
2) 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.
(1) Stopping distance
(2) 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:
Maximum brake force ▶
FBmax = wheel load FR x coefficient of
frictionMh
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.
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.

10-154892-01
Slip ▶
The brake slip is the difference between the vehicle speed and the wheel circumference speed. If
the wheel locks, the slip is greatest, that is 100 %. If the wheel is running freely and un-braked,
the slip is the lowest, equal to 0 %. Slip can be calculated from the vehicle speed Vveh and the
wheel speed Vw. The equation for this is:
Vveh = 100 km/h, Vw = 70 km/h
Slip ratio (S) = X 100%
S = 30%Vveh - Vw
Vveh
Typical Slip Curves ▶
For the various road conditions, the friction
coefficients were plotted. The typical course
of the curves is always the same. The only
special feature is shown by the curve for
freshly fallen snow, for this curve increases
at 100 % slip. In a vehicle without ABS, the
wheel locks on braking and therefore
pushes a wedge before it. This wedge of
loose surface or freshly fallen snow means
and increased resistance and as a result the
stopping distance is shorter. This reduction
in stopping distance is not possible with a
vehicle with ABS, as the wheel does not
lock. On these surfaces the stopping
distance with ABS is longer than without
ABS. The reason for this is based in physics
and not in the Anti-Lock System.
However, as mentioned before, ABS is not
about the stopping distance, but
maneuverability and driving stability, for the
vehicle with locking wheels without ABS
cannot be steered. Ex)