1998 SSANGYONG MUSSO wheel

4F-6 ANTILOCK BRAKE SYSTEM
ABS,ABS/ABD
COMPONENT LOCATOR
1 ABS Hydraulic Unit
2 ABS/ABD Hydraulic Unit
3 Diagnosis Socket
4 Front Wheel Speed Sensor
5 Front Impulse Ring6 Rear Wheel Speed Sensor
7 Rear Impulse Ring
8 ABS Warning Indicator Light
9 TCS Indicator Light
1 0 ABS/ABD ECU

ANTILOCK BRAKE SYSTEM 4F-7
ABD SYSTEM DESCRIPTION
General:
The Automatic Brake Differential Lock (ABD) is a traction system by means of brake intervention only, available in
a low speed range (< 60kph).
It workes on m-split roads with sidewise different friction coefficients.
The spinning driven wheel is braked and the drive torque can be transferred to the wheel on the high- m side.
During ABD active, the ABD information lamp is blinking.
The temperature of the brakes is calculated by a mathematical model and ABD is switched passive if the calculated
temperature is greater than a threshold value(500°C).
ABD is permitted again, when the calculated temperature is less than 350°C.
Control Algorithm:
The input signals for the control algorithm are the filtered
wheel speed signals from the ABS speed processing.
With the speed difference of the driven wheels, the control
deviation is calculated.
If the control deviation exceeds a certain threshold value,
the wheel with the greater slip is braked actively.
The threshold value depends on the vehicle speed:
It is reduced with increasing vehicle speed down to a constant
value.
Pressure Modulation:
Depending on the control deviation and the wheel acceleration of the spinning wheel, pressure increase, hold and
decrease are made.
The pressure modulation is done with the conventional control with the valves. ASV, USV, EV and AV according
the the following table:
Speed Range:
ABD is available in the speed range £ 60 kph.
Above 60 kph vehicle speed, ABD is passive.
It is possible to initiate ABD operation up to a vehicle speed of 55kph.
Increase
Open Open Open ASVDecrease Hold
Closed Closed Closed
Closed Closed Open
Open Closed Closed USV
EV
AV
Speed difference driven wheels [kph]
18
6
1260ABD operation
Vehicle
speed
[kph]

4F-8 ANTILOCK BRAKE SYSTEM
Temperature Model:
ABD operation is a high thermal load for the brakes.
To avoid any damages at the brakes, the disk temperature is calculated with a mathematical model for each driven
wheel separately. After ignition on, the calculation starts with 30°C and then three different phases are evaluated
separately and added:
ABD operation, braking and coling phase.
If the temperature is highter than 500°C, ABD is disabled for this wheel.
It is permitted again, if the model has calculated down the 350°C.
Lamp Concepts:
The system is equipped with an ABD information lamp, which is blinking during ABD operation.
The activation of the EBD, ABS warning lamp and the ABD info lampo is summarized in the following table:
Ignition
ONABS
OperationABD
OperationSystem failure
(EBD,ABS or ABD are
not distinguished)ABD passive due
to temperature
model
ABS warning
lamp
ABD info
lamp
EBD warning
lamp2s on for lamp
check
2s on for lamp
check
2s on for lamp
checkOFF
EBD operation
/ OFFOFFOFF
Dlinking
(Flashing)
OFFON
OFF
ONOFF
OFF
OFF

ANTILOCK BRAKE SYSTEM 4F-13
DEFECT CODES
Description
-
Replace the ECU
lCheck resistance of the wheel speed sensor :
1.280KW - 1.920KW
lCheck wire for ground and open.
lReplace the sensor.
lCheck resistance of the wheel speed sensor :
1.280KW - 1.920KW
lCheck wire for ground and open.
lReplace the sensor.
lCheck resistance of the wheel speed sensor :
1.280KW - 1.920KW
lCheck wire for ground and open.
lReplace the sensor.
lCheck resistance of the wheel speed sensor :
1.280KW - 1.920KW
lCheck wire for ground and open.
lReplace the sensor.
lCheck wire for ground and open.
lCheck connection of the wheel speed sensor connec-
tor and ECU side connector.
lMeasure air gap between wheel teeth and wheel speed
sensor and check installation of wheel tooth.
(Standard air gap : 0.35 - 1.60 mm)
lCheck output voltage of the sensor by rotating the
wheel 1/2 - 1 revolution per second and shaking sen-
sor wire.
- When measured by multi - meter (AC) :
output voltage > 70 mV
- When measured in oscilloscope :
output voltage ³ 120 mV/P-P
lReplace the sensor.
lCheck wire for ground and open.
lCheck connection of the wheel speed sensor. con-
nector and ECU side connector.
lMeasure the air gap between wheel teeth and wheel
speed sensor and check installation of wheel tooth.
(Standard air gap : 0.35 - 1.60 mm)
lCheck output voltage of the sensor by rotating the
wheel 1/2 - 1 revolution per second and shaking sen-
sor wire. Defect Code
01
02
03
04
05
06
07
08Application
Normal
Defective ECU
Front/left Wheel Speed
Sensor (Wire)
Front/right Wheel Speed
Sensor (Wire)
Rear/left Wheel Speed
Sensor (Wire)
Rear/right Wheel Speed
Sensor (Wire)
Front/left Wheel Speed
Sensor (Signal)
Front/right Wheel Speed
Sensor (Signal)

4F-14 ANTILOCK BRAKE SYSTEM
Description
- When measured by multi - meter (AC) :
output voltage > 70 mV
- When measured in oscilloscope :
output voltage ³ 120 mV/P-P
lReplace the sensor.
lCheck wire for ground and open.
lCheck connection of the wheel speed sensor con-
nector and ECU side connector.
(Standard air gap : 0.15 - 1.20 mm)
lCheck output voltage of the sensor by rotating the
wheel 1/2 - 1 revolution per second and shaking sen-
sor wire.
- When measured by multi - meter (AC) :
output voltage > 70 mV
- When measured in oscilloscope :
output voltage ³ 120 mV/P-P
lReplace the sensor.
lCheck wire for ground and open.
lCheck connection of the wheel speed sensor con-
nector and ECU side connector.
lMeasure air gap between wheel teeth and wheel
speed sensor and check installation of wheel tooth.
(Standard air gap : 0.15 - 1.20 mm)
lCheck output voltage of the sensor by rotating the
wheel 1/2 - 1 revolution per second and shaking sen-
sor wire.
- When measured by multi - meter (AC) :
output voltage > 70 mV
- When measured in oscilloscope :
output voltage ³ 120 mV/P-P
lReplace the sensor.
lCheck number of teeth on the wheel rotor and its
condition.
- Number of teeth : 52
lCheck valve relay voltage.
lCheck connection of connector and terminals in the
ECU and hydraulic modulator.
lCheck ground.
lCheck terminals for open or short.
(When connector is removed)
lReplace the hydraulic modulator. Defect Code
09
10
11
12Application
Rear/left Wheel Speed
Sensor (Signal)
Rear/right Wheel Speed
Sensor (Signal)
Wheel Rotor
Valve Relay

ANTILOCK BRAKE SYSTEM 4F-19
MAINTENANCE AND REPAIR
ON-VEHICLE SERVICE
WHEEL SPEED SENSOR
1 Bolt
2 Front Wheel Speed Sensor
3 Knuckle4 Bolt
5 Rear Wheel Speed Sensor
6 Rear Axle

ANTILOCK BRAKE SYSTEM 4F-21
HYDRAULIC CIRCUIT
ABS 5.3
Pressure Increased
1 Master Cylinder
2 Hydraulic Unit
3 Damping Chamber
4 Return Pump
5 Return Pump Motor6 Accumulator Chamber
7 Inlet Valve for Each Wheel
8 Outlet Valve for Each Wheel
9 Front Wheel
10 Rear Wheel

4F-22 ANTILOCK BRAKE SYSTEM
Pressure Decreased
1 Master Cylinder
2 Hydraulic Unit
3 Damping Chamber
4 Return Pump
5 Return Pump Motor6 Accumulator Chamber
7 Inlet Valve for Each Wheel
8 Outlet Valve for Each Wheel
9 Front Wheel
10 Rear Wheel