Page 372 of 801

YH4
GRAND
VITARA
ANTILOCK BRAKE SYSTEM (ABS) (OPTIONAL) 5E1-31
1. Diagnosis
connector
(6 pins connector)
2. Diag. switch
terminal
3. Ground
4. Service wire
Brake
pedal
Ignition
sw.
Motor
Solenoid
Rear3.0 sec.
3.0
ON-VEHICLE SERVICE
PRECAUTION
When connector are connected to ABS hydraulic unit / control mod-
ule assembly, do not disconnect connectors of sensors and turn
ignition switch ON. Then DTC will be set in ABS control module.
ABS HYDRAULIC UNIT OPERATION CHECK
1) Check that basic brake system other than ABS is in good condi-
tion.
2) Check that battery voltage is 11V or higher.
3) With ªABSº warning lamp, check that no abnormality is de-
tected in ABS. Refer to ªDIAGNOSTIC TROUBLE CODE
(DTC) CHECKº in this section.
4) Lift up vehicle.
5) Set transmission to neutral and release parking brake.
6) Turn each wheel gradually by hand to check if brake dragging
occurs. If it does, correct.
7) With diag. switch terminal of diagnosis connector connected to
ground by using service wire, turn ignition switch ON and check
if ªABSº warning lamp indicates DTC 12.
8) Turn ignition switch OFF.
9) Perform following checks with help of another person.
Brake pedal should be depressed and then ignition switch
turned ON by one person and wheel should be turned by
another person's hand. At this time, check that:
Operation sound of solenoid is heard and wheel turns only
about 0.5 sec. (Brake force is depressurized).
Operation sound of pump motor is heard and pulsation is felt
at brake pedal.
10) If all 4-wheels cannot be checked during one ignition cycle
(OFF ON), repeat Steps 8) and 9) till all 4 wheels are
checked.
If a faulty condition is found in Steps 9) and 10), replace hydrau-
lic unit / control module assembly.
11) Turn ignition switch OFF and remove service wire from diagno-
sis connector.
Page 373 of 801

YH4
GRAND
VITARA
5E1-32 ANTILOCK BRAKE SYSTEM (ABS) (OPTIONAL)
1. ABS hydraulic
unit /control
module
assembly
2. Brake pipe
1. ABS hydraulic
unit / control
module connector 1. Brake pipe
2. ABS hydraulic unit /
control module assembly
3. Bracket
ABS HYDRAULIC UNIT / CONTROL MODULE
ASSEMBLY
CAUTION:
Never disassemble ABS hydraulic unit / control module as-
sembly, loosen blind plug or remove motor. Performing any
of these prohibited services will affect original performance
of ABS hydraulic unit / control module assembly.
HYDRAULIC UNIT INSPECTION
Check hydraulic unit for fluid leakage.
If any, repair or replace.
REMOVAL
1) Disconnect negative cable at battery.
2) Using special tool, disconnect brake pipes from ABS hydraulic
unit / control module assembly and loosen flare nuts as shown
figure.
Special Tool
(A): 09950-78220
NOTE:
Put bleeder plug cap onto pipe to prevent fluid from spilling.
Do not allow brake fluid to get on painted surfaces.
3) Disconnect ABS hydraulic unit / control module assembly con-
nector.
Page 374 of 801
YH4
GRAND
VITARA
ANTILOCK BRAKE SYSTEM (ABS) (OPTIONAL) 5E1-33
1. ABS hydraulic unit /
control module
assembly
2. Nut
1. To left-front
2. To right-front
3. To rear
4. From master cylinder4) Remove three nuts and take out ABS hydraulic unit / control
module assembly from bracket.
CAUTION:
Do not give an impact to hydraulic unit.
Use care not to allow dust to enter hydraulic unit.
Do not place hydraulic unit on its side or upside down.
Handling it in inappropriate way will affect its original
performance.
INSTALLATION
1) Install hydraulic unit by reversing removal procedure.
Tightening Torque
(a): 16 N
.m (1.6 kg-m, 12.0 lb-ft)
(b): 21 N
.m (2.1 kg-m, 15.5 lb-ft)
(c): 10 N
.m (1.0 kg-m, 7.5 lb-ft)
2) Bleed air from brake system. Refer to ªBLEEDING BRAKESº in
Section 5.
3) Check each installed part for fluid leakage and perform hydraulic
unit operation check.
Page 375 of 801
YH4
GRAND
VITARA
5E1-34 ANTILOCK BRAKE SYSTEM (ABS) (OPTIONAL)
1. Left front wheel speed sensor
2. Left front strut
3. Sensor rotor
1. Wheel speed sensor connector
1. Peak-to-peak voltage
FRONT WHEEL SPEED SENSOR
OUTPUT VOLTAGE INSPECTION
1) Turn ignition switch OFF.
2) Hoist vehicle a little.
3) Disconnect connector of wheel speed sensor.
4) Connect voltmeter between connector terminals.
5) While turning wheel at a speed of approximately 2 / 3 to 1 full
rotation per second, check AC voltage of sensor.
Output AC voltage at 2 / 3 to
one rotation per second (35 ± 53 Hz): 106 mV or more
If measured voltage is not as specified, check sensor, rotor and
their installation conditions.
Reference
When using oscilloscope for this check, check if peak-to-peak volt-
age meets specification and waveform is complete.
Peak-to-peak voltage
at 2 / 3 to one rotation per second (35 ± 53 Hz): 150 mV or more
Page 376 of 801

YH4
GRAND
VITARA
ANTILOCK BRAKE SYSTEM (ABS) (OPTIONAL) 5E1-35
FORWARD
1. Front wheel speed
sensor connector
2. Headlight assembly
1. Front wheel speed sensor
2. Bolt
REMOVAL
1) Disconnect negative cable at battery.
2) Hoist vehicle and remove wheel.
3) Disconnect front wheel speed sensor connector.
4) Remove harness clamp bolts and remove front wheel speed
sensor from knuckle.
CAUTION:
Do not pull wire harness when removing front wheel
speed sensor.
Do not cause damage to surface of front wheel speed
sensor and do not allow dust, etc. to enter its installa-
tion hole.
SENSOR INSPECTION
Check sensor for damage.
Check sensor for resistance.
Resistance between terminals: 1.2 ± 1.6 k at 20C (68F)
Resistance between terminal and sensor body: 1 M or more
If any faulty is found, replace.
SENSOR ROTOR INSPECTION
Check rotor for being missing, damaged or deformed.
Turn drive shaft and check if rotor rotation is free from eccentricity
and looseness.
Check that no foreign material is attached.
If any faulty is found, repair or replace. Refer to WHEEL HUB RE-
MOVAL and INSTALLATION in Section 3D.
Page 377 of 801
YH4
GRAND
VITARA
5E1-36 ANTILOCK BRAKE SYSTEM (ABS) (OPTIONAL)
1. Front wheel speed sensor
2. Bolt
INSTALLATION
1) Check that no foreign material is attached to sensor and rotor.
2) Install it by reversing removal procedure.
CAUTION:
Do not pull wire harness or twist more than necessary
when installing front wheel speed sensor.
Fit harness grommet to inner fender securely.
Tightening Torque
(a): 10 N
.m (1.0 kg-m, 7.5 lb-ft)
(b): 23 N
.m (2.3 kg-m, 17.0 lb-ft)
3) Check that there is no clearance between sensor and knuckle.
FRONT SENSOR ROTOR
REMOVAL
Remove front sensor rotor referring to WHEEL HUB REMOVAL in
Section 3D.
INSTALLATION
CAUTION:
Don't reuse front sensor rotor removed from front wheel
hub because of it for being deformed.
Install new front sensor rotor referring to WHEEL HUB INSTALLA-
TION in Section 3D.
Page 378 of 801
YH4
GRAND
VITARA
ANTILOCK BRAKE SYSTEM (ABS) (OPTIONAL) 5E1-37
1. Rear wheel speed sensor
2. Sensor rotor
3. Rear axle housing
1. Rear wheel speed
sensor harness
2. Connector
1. Sensor bolt
2. Clamps
REAR WHEEL SPEED SENSOR
OUTPUT VOLTAGE INSPECTION
Check in the same procedure as that used of front wheel speed
sensor check.
Output AC voltage at 2 / 3 to
one rotation per second (25 ± 38 Hz): 106 mV or more
Reference
When using oscilloscope,
peak-to-peak voltage at 2 / 3 to
one rotation per second (25 ± 38 Hz): 150 mV or more
REMOVAL
1) Disconnect negative cable at battery.
2) Hoist vehicle.
3) Disconnect rear wheel speed sensor connector and detach wire
harness from vehicle body and rear axle.
4) Remove harness clamps and remove rear wheel speed sensor
from rear axle.
CAUTION:
Do not pull wire harness when removing rear wheel
speed sensor.
Do not cause damage to surface of rear wheel speed
sensor and do not allow dust, etc. to enter its installa-
tion hole.
Page 379 of 801
YH4
GRAND
VITARA
5E1-38 ANTILOCK BRAKE SYSTEM (ABS) (OPTIONAL)
1. Clamps
2. Sensor bolt
SENSOR INSPECTION
Check sensor (pole piece) for damage or bent.
Check sensor for resistance.
Resistance between
terminals : 1.2 ± 1.6 k at 20C, 68F
Resistance between
terminal and sensor body: 1 M or more
If any faulty is found, replace.
SENSOR ROTOR INSPECTION
Check rotor serration (teeth) for being missing, damaged or de-
formed.
Turn wheel and check if rotor rotation is free from eccentricity and
looseness.
Check that no foreign material is attached.
If any faulty is found, repair or replace.
INSTALLATION
1) Check that no foreign material is attached to sensor and rotor.
2) Install it by reversing removal procedure.
Tightening Torque
(a): 21 N
.m (2.1 kg-m, 15.0 lb-ft)
CAUTION:
Do not pull wire harness or twist more than necessary
when installing rear wheel speed sensor.
3) Check that there is no clearance between sensor and knuckle.