1998 JAGUAR X308 wheel

Parking Brake and Ac
tuation - Pa
rking Brake Cable Adjustment
Gen
eral Procedures

1.
Raise rear of vehicle and support on stands. See section 100-
02.
2. Make sure gear selector is in neutral position.

3. Adjust parkin
g brake cable.
R

otate adjusting nut, until
the parking brake can be
applied by raising the parking brake lever 3 to 5 clicks.
4. CAUTION: Make sure that th e rear wheels rotate freely
when the parking brake lever is released.
Remove stands an d lower vehicle.

Parking Brake and Actuation - P
arking Brake Shoe
and Lining Adjustment
Gene
ral Procedures
1. Raise rear of vehicle and support on stands. See section 100-
02.
2. Remove both rear wheels.
3. Make sure that the parking br ake lever is in the released
position, and the gear selector lever is in neutral (N).

4. Alig
n brake disc access hole
with parking brake adjuster.
Instal
l three wheel nuts to secure brake disc to hub.
Tighten nuts to 20 Nm.
R e
move plug from access hole.
Rotate
brake disc un
til ac
cess hole is aligned with
adjuster.

5. Using a flat-bladed screwdriv er rotate the adjuster
anti
clockwise until the brake disc cannot be rotated.

6. NOTE : Th
e brake shoe return-spring next to the adjuster
prevents the adjuster from rota ting under normal operating
conditions. Make sure that the spring is seated between the
adjuster spokes, when brake adjustment is complete.
Rotate the adjuster gradually clockwise until the brake disc
rotates freely.
Inst al
l plug to access hole.
7. Repeat parking brake setting pr ocedure on opposite-side of
vehicle.
8. CAUTION: Make sure that th e rear wheels rotate freely
when the parking brake lever is released.
Adjust parking brake cable.
Ro
tate adjusting nut, until the parking brake can be
applied by raising the parking brake lever 3 to 5 clicks.

9.
Re
move wheel nuts.
10. Fit rear wheels. See section 204-04.
11. Remove stands an d lower vehicle.

Parking Brake and Actuation - P
arking Brake Shoes
Re
mo
val and Installation
Remov
a
l
W
A
RNING: BRAKE DUST, IF INHALED CAN DAMAGE YOUR
HEALTH. ALWAYS REMOVE BRAKE DUST USING A VACUUM
BRUSH. DO NOT USE A COMPRESSED-AIR LINE TO DISPERSE BRAKE DUST INTO THE ATMOSPHERE.
CAUTION: Replacement of nuts and bolts: Various thread-locking devices are used on nuts and bolts throughout the
vehicle. These devices restrict the number of times a nut or bolt can be used. See section 100-00 for information.
1. Ra
ise rear of vehicle and support
on stands. Refer to section
100-02.
2. Remove both rear wheels.
3. Remove both rear brake discs. Refer to operation 70.10.13.

4. Re
move front shoe retaining pin.
Align hub ac

cess hole with retaining pin.
Turn pin until
it rel
eases
from backing plate.

5. Remove adju ster assembly.
Move front shoe forwards.

Remove adju
ster assembly.

6. Re
move rear shoe retaining pin.
Al
ign hub ac
cess hole with retaining pin.
Turn pin until
it rel
eases
from backing plate.
7. Remove brake shoes from parkin g brake lever-mechanism and
remove shoes from vehicle.
8. Remove return sp rings from shoes.

plate.
Install front
shoe
retaining pin.
Align hu
b acc
ess hole.
Inst
al
l retaining pin.
5. Make sure brake shoes are seat ed correctly in adjuster and
lever mechanism.
6. Repeat procedure to install parking brake shoes on opposite
side of vehicle.
7. Install both rear br ake discs. Refer to operation 70.10.13.
8. Set parking brake. Refer to operation 70.35.37.
9. Fit rear wheels. See section 204-04.
10. Remove stands an d lower vehicle.

Anti-Lock Control -
Lubri
cants, Fluids, Sealants and Adhesives
Torques
Brake Tube, Hoses and Bracket Torques
CAUTI
ON: Replacement of
nuts and bolts: Various thread-locking devices are used on nuts and bolts throughout the
vehicle. These devices restrict the number of times a nut or bolt can be used. See section 100-00 for information.


UnitS
pecification
Brake flu

id
ITT Supe
r Dot 4
Com

ponent
Nm
Bol

t - front wheel speed sensor
8-
10
Bolt

- rear wheel speed sensor
8-
10
Bo

lt - hydraulic control unit to bracket
8-
10
Bolt -

hydraulic control unit bracket to body
10
-14
Hub rotor nut2

70-330
Com

ponent
Nm
Bleed n

ipple - front
4-
6
Bleed n

ipple - rear
8-1
1
Hose to fr

ont caliper
10
-14
Hose banjo to rear caliper -

bolt
30
-40
M1

0 hose locknut
15
-20
M10

brake tube female-nut
13
-17
M10

brake tube male-nut
13
-17
M12

brake tube male-nut
15
-20
M18

brake tube male-nut
22
-28
Brake tube clip retention

-bracket to body
4-
6

Anti-Lock Control - Anti-Lock Control
Description and Operation


Wheel Spe
ed Sensors
Each
wheel is monitored by a wheel speed se n
sor, to detect the speed of movement of
a toothed gear that is driven by the
wheel. Signal's generate d by the toothed gear passing th e sensor are sent to the ABS/TCCM to communicate the speed of
wheel rotation and any rapid change of wheel speed.
The frequency of the sinusoidal output voltag e signal from the sensor, is proportional to road wheel rotational speed and the
number of teeth on the toothed gear. The amplitude of the volt age is dependent upon the 'air gap' between the sensor and
toothed wheel, therefore it is important that this preset gap remains clear and undisturbed.
Ite
m
De
scr
iption
1Pe
dal Housi
ng / Booster - refer to 206-07
2Vac
u
um Hose - refer to 206-07
3Mas
t
er Cylinder / Reservoir - refer to 206-06
4Pri
m
ary Brake Circuit - refer to 206-06
5Sec

ondary Brake Circuit - refer to 206-06
6Hydraulic

Pump / Motor Unit
7ABS/Traction

Control Control Module (ABS/TCCM)
8Hydraulic Cont

rol Unit (HCU)
6/
7/
8
Br
ak
e Control Modulator
9Brake
Di
sc - refer to 206-03 or 206-04
10Brake
Cali
per - refer to 206-03/206-04
11Wh
ee
l Speed Sensor
12ABS Warning Lamp
13Brake
Fl
uid Level Warning-Lamp - refer to 206-06

It is a reciprocating two
-circuit pu
mp in which one brake circuit is as signed to each pump circuit.
It supplies th
e fluid pressure and vo
lume to supply the brake circuits under ABS and Traction control.
The pump is driven by an electri
c motor, with the pump
housing incorporating two lo w pressure accumulators and
damping chambers for each brake circuit.
The ac cu
mulator stores the pressure and smooths out the output pu
lses from the pump.
ABS Warning Lamp
The sys
tem will be set in a fail-safe mode if a problem is de
tected; a warning lamp on the instrument panel will notify the
driver there is a problem.
Anti-Lock Braking Sy
stem (ABS)
The AB
S components are combined with
an hydraulic booster and a tandem master cylinder to provide a two circuit braking
system. The system comprises, four wheel speed sensor s, a brake control modulator and an ABS warning lamp.
Should a wheel start to lock-up during braking a signal tr ansmitted from the wheel speed sensor to the brake control
modulator will start the hydraulic pump. The brake control modula tor will close the input valve of the line connected to the
locked-wheel to stop any increase in fluid pressure to the br ake caliper. If this fails to prevent the wheel locking, the
pressure in the caliper will be decreased by opening the return valve until th e wheel starts accelerating again. The fluid
pressure from the return va lve is directed into the low pressure accumulator, housed in the pump.
From the low pressure accumulator, fl uid is pumped through the damping cham ber to the brake master cylinder. The
pressure to the brake caliper will then be increased in small steps to maintain maximum adhesion between the tire and road
surface. This is achieved by closing the return valve, and opening the input valve and using the hydraulic pump to increase
the pressure.
Although the system senses all four wheels independently, the rear wheels are regulated as a pair. If a sensor on a rear
wheel detects a wheel decelerating rapidly, then the fluid pressure to both wheels is reduced. The fluid pressure is then
dictated by the wheel having the lowe st adhesion with the road surface.
The ABS system will be set in a fail-safe mode if a problem is detected; a warn ing lamp on the instrument panel will notify
the driver there is a problem. The brake system will still operate conventionally and with the same standard of performance
as a vehicle not equipped with ABS.
Automa tic Stability Control (ASC)

Th
e ASC utilizes the ABS sensing arrangement to provide the maximum traction force to propel the vehicle.
The ASC is switched on when the engine is started. The system can be switched off by pressing the 'ASC OFF' (the switched
is marked 'TRAC OFF' on vehicles fitted with traction control). The switch, which is situated in the center console switchpack,
lights up to warn that the system is sw itched off. An 'ASC' amber warning light flashes on the instrument panel when the
system detects a spinning wheel.
The ASC system uses engine intervention to reduce the torque delivered to the drive wheels to prevent them spinning.
Engine torque is re duced in three ways:
The
throttle is moved towards the closed position.
The ignition is retarded. F
u
el is cut-off at the cylinder injectors.
Wheel spin is detected by the wheel sp eed sensors and communicated to the AB S/TCCM. The ABS/TCCM uses information
from the controller area network (CAN) to calculate the torque that the engine should produce to stop the wheel spinning.
Torque reductions are then requested from the engine control module (ECM ) through the CAN. The throttle is then
positioned to provide the target torque, which has been calculated to prevent wheel spin. During the transient phase of
torque reduction the fuel is cut-off and th e ignition retarded Both the fuel cut-off an d ignition retard will be restored to
normal when the throttle is set to its new position.
The ASC uses a brake control modulator with six solenoid va lves: three normally open inlet valves and three normally