NOTE: Wheel speed sensor should be installed all
the way into the clamping bushings, the wheel
speed sensor will self adjust when the vehicle is
moved.

The ABS brake system uses 4 wheel speed sensors.

A sensor is mounted to each front hub/bearings in
the front. A rear sensor is mounted to each rear sup-
port plate.

OPERATION

The Wheel Speed Sensor consists of a magnet sur-

rounded by windings from a single strand of wire.
The sensor sends a small AC signal to the CAB. This
signal is generated by magnetic induction. The mag-

netic induction is created when a toothed sensor ring
(exciter ring or tone wheel) passes the stationary
magnetic WSS.

When the ring gear is rotated, the exciter ring

passes the tip of the WSS. As the exciter ring tooth
approaches the tip of the WSS, the magnetic lines of
force expand, causing the magnetic field to cut across
the sensor’s windings. This, in turn causes current to
flow through the WSS circuit (Fig. 1) in one direc-
tion. When the exciter ring tooth moves away from
the sensor tip, the magnetic lines of force collapse
cutting the winding in the opposite direction. This
causes the current to flow in the opposite direction.
Every time a tooth of the exciter ring passes the tip
of the WSS, an AC signal is generated. Each AC sig-
nal (positive to negative signal or sinewave) is inter-
preted by the CAB. It then compares the frequency of
the sinewave to a time value to calculate vehicle
speed. The CAB continues to monitor the frequency

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BRAKES - ABS

to determine a deceleration rate that would indicate
a possible wheel-locking tendency.

The signal strength of any magnetic induction sen-

sor is directly affected by:

• Magnetic field strength; the stronger the mag-

netic field, the stronger the signal

• Number of windings in the sensor; more wind-

ings provide a stronger signal

• Exciter ring speed; the faster the exciter ring/

tone wheel rotates, the stronger the signal will be

• Distance between the exciter ring teeth and

WSS; the closer the WSS is to the exciter ring/tone
wheel, the stronger the signal will be.

FRONT WHEEL SPEED SEN-
SOR

REMOVAL

(1) Raise and support the vehicle.
(2) Remove the front wheels.
(3) Pull the wheel speed sensor out of the front

wheel hub (Fig. 2).

(4) Only do this step if sensor replacement is

necessary. Cut through the wheel speed sensor
cable at an easily accessible point (Fig. 2).

(5) Remove clamping sleeve from the knuckle if

damaged or being replaced with new sensor (Fig.
2).

INSTALLATION

(1) Connect separate wheel speed sensor cables

with shrink-fit sleeves and shrink-fit tubing (Fig. 2).
Only do this step if replacing the sensor.

(2) Install the clamping bushing into the knuckle

(Fig. 2) Only do this step if replacing the sensor
or the clamping bushing was damaged.

(3) Install the wheel speed sensor all the way into

the front wheel hub the wheel speed sensor will self
adjust when the vehicle is moved (Fig. 2).

(4) Install the front wheels.
(5) Lower the vehicle.

REAR WHEEL SPEED SENSOR

REMOVAL

(1) Raise and support the vehicle.
(2) Remove the rear wheels.
(3) Pull the wheel speed sensor out of the mount-

ing hole in the axle supporting tube (Fig. 3).

(4) Only do this step if sensor replacement is

necessary. Cut through the wheel speed sensor
cable at an easily accessible point (Fig. 3).

(5) Remove clamping sleeve from the knuckle if

damaged or being replaced with new sensor (Fig.
3).

Fig. 1 Operation of the Wheel Speed Sensor

1 - MAGNETIC CORE
2 - CAB
3 - AIR GAP
4 - EXCITER RING
5 - COIL

Fig. 2 FRONT WHEEL SPEED SENSOR

1 - SHRINK-FIT SLEEVE
2 - CLAMPING BUSHING
3 - SPEED SENSOR
4 - SHRINK TUBE

BRAKES - ABS

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INSTALLATION

(1) Connect separate wheel speed sensor cables

with shrink-fit sleeves and shrink-fit tubing (Fig. 3).
Only do this step if replacing the sensor.

(2) Install the clamping bushing into the knuckle

(Fig. 3) Only do this step if replacing the sensor
or the clamping bushing was damaged.

(3) Install the wheel speed sensor all the way into

the axle tube, the wheel speed sensor will self adjust
when the vehicle is moved (Fig. 3).

(4) Install the rear wheels.
(5) Lower the vehicle.

TONE WHEEL

REMOVAL

(1) Remove

the

hub/bearing

assembly

(DRW)

(Refer to 3 - DIFFERENTIAL & DRIVELINE/REAR
AXLE/AXLE BEARINGS - REMOVAL).

(2) Insert a hooked prybar between the hub/bear-

ing and the inside of the tone wheel and pry upwards
slightly and work your way around the tone wheel
until the wheel is loose (Fig. 4).

(3) Remove the tone wheel.

INSTALLATION

(1) Install the tone wheel to the hub/bearing with

a thin bead of silicone around the tone wheel.

(2) Tap the tone wheel down with a soft hammer

until seated.

(3) Install the hub/bearing (DRW) (Refer to 3 -

DIFFERENTIAL & DRIVELINE/REAR AXLE/AXLE
BEARINGS - INSTALLATION).

STEERING ANGLE SENSOR

DESCRIPTION

Fig. 3 REAR WHEEL SPEED SENSORS

1 - SHRINK-FIT SLEEVE
2 - SPEED SENSOR
3 - CLAMPING BUSHING
4 - SHRINK TUBE

Fig. 4 TONE WHEEL REMOVAL

1 - HOOKED PRYBAR
2 - TONE WHEEL
3 - HUB/BEARING ASSEMBLY

Fig. 5 STEERING ANGLE SENSOR

1 - UPPER STEERING COLUMN COVER
2 - CLOCKSPRING
3 - STEERING ANGLE SENSOR
4 - LOWER STEERING COLUMN COVER
5 - FRONT COVER
6 - STEERING ANGLE SENSOR ELECTRICAL CONNECTION

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BRAKES - ABS

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