2005 JAGUAR S TYPE steering

JAGUARS-TYPEOccupant Protection
33
Airbags
Driver Airbag
The driver airbag module is fitted in the centre of
the steering wheel and is of conventional design.
A reduced charge propellant (Ôde-poweredÕ) is
used to minimise impact effects where the driver
is seated close to the wheel.
The module is secured by two side screws on the
left and right underside of the steering wheel.
Passenger Airbag
WARNING:
Do not place objects on the passenger airbag
deployment panel. Injury could occur if the
airbag contacts an object during inflation.
The passenger airbag uses a heated gas inflator
(HGI) system instead of a solid propellant. This
system is inherently ÔcleanÕ since the inflation gas
is a lean hydrogen/air mixture and the by-
products are water vapour and air. Although the
gas is not classified as an explosive, the possible
effects of accidental deployment when handling
or working close to the unit are similar to those of
other types of airbag. It is recommended that
current safety procedures are also followed when
handling the HGI modules.
The HGI airbag module has fewer components
than previous types, consisting of:
¥ 140 litre bag
D.501.1776
CENTER REAR SEAT BELT RETRACTOR ASSEMBLIES
J.501.1785
PASSENGER AIRBAG
¥ Aluminium pressure vessel containing a
mixture of 12% hydrogen/88% air at a
pressure of 180 bar.
¥ Pressure vessel end plug with burst disc.
¥ Pyrotechnic igniter assembly fitted to
pressure vessel end plug.
The igniter is electrically triggered from the
Restraints Control Module (RCM). When triggered,
the igniter fires a high speed ÔdartÕ along the
length of the pressurised cylinder, producing a
heated trail (due to friction) which causes rapid
and even combustion of the gas throughout the
cylinder. The igniter also ruptures the burst disc in
the end plug, allowing the expanding gases from

JAGUARS-TYPEChassis
47
Front Suspension
The independent front wheel suspension is a
double wishbone axle arrangement with
aluminium control arms. The two arms are of
different lengths, which minimises the changes in
track and camber. Inclination of the upper control
arm axis provides anti-dive front suspension
action. There are two front cross members,
known as Number 1 and Number 2.
Number 1, the forward cross member, is a steel
fabrication, non-isolated, which locates the lower
control arm front mounting, the anti-roll bar and
the cooling module.
The rear cross member, Number 2, is an
aluminium casting, non-isolated and it locates the
lower control arm rear mounting, the power
steering rack and the engine hydro-mounts.
WARNING: No attempt must be made to
weld or repair the aluminium cross
member. If it is damaged, a new one must
be installed.
Lower Control Arm
The lower control arm is an aluminium forging
and has locations for the damper and the anti-roll
bar drop link. It is mounted with one hydro-bush,
the front lower bush, and one rubber bush, both
serviceable. This is the first time that a hydraulic
bush has been fitted to a Jaguar wishbone. The
hydro-bush is tuned for refinement and helps to
J.204.402
reduce brake vibration.
Service adjustments for caster and camber can be
made to the lower control arm geometry with the
addition of cam bolts (not supplied with the
vehicle).
LOWER CONTROL ARM
J.204.402
Lower
Control Arm
Anti-roll BarAnti-roll Bar
Drop Link

JAGUARS-TYPE
D.204.400
Chassis
48
D.204.440
VERTICAL FRONT KNUCKLE UPPER CONTROL ARM
D.204.440
D.204.400
Upper Control Arm
The upper control arm is also an aluminium
forging, mounted with two rubber bushes and has
an integral, non-serviceable ball joint.
Vertical Front Knuckle
The vertical front knuckle is an aluminium casting
with integral steering arm, installed between the
upper and lower control arms. The lower ball joint
is serviceable and is a press fit. The knuckle
locates the upper balljoint, riveted disk shield and
brake calliper and wheel bearing/hub. The wheel
bearing is a new type and contains the integral
ABS rotor and sensor. The bearing is not
serviceable and must be replaced as a complete
unit. A service kit is available for the ABS sensor.
Vertical Front Knuckle
Disc Shield
Wheel
Bearing/Hub

JAGUARS-TYPEChassis
56
D.206.177
current vehicles and the 12 valve unit has a 47-
way connector with lever cam. DSC calculates the
real vehicle motion (forward and gearing) and
compares it to the direction initially chosen by the
driver. A steering rate sensor is located on the
steering column and is used to calculate steering
angle. A yaw rate sensor and lateral accelerometer
are located on a bracket behind the hand brake
lever and are used to calculate the vehicle under
or over steer and any side slip.
As soon as DSC recognises that the driver is not
reacting sufficiently to compensate a deviation,
DSC intervenes by applying brake force to each of
the four wheels individually to control yaw
Front Wheel Sensor
The front wheel active ABS speed sensors are
incorporated into the wheel bearings, connected
via a flying lead routed along the brake hose.
Rear Wheel Sensor
The rear sensors are mounted on the hub carrier
and connected by a flying lead routed along the
control arm. None of the sensors are adjustable.
Wheel speed sensors are new active sensors,
which are more sensitive at lower speeds that the
current saloon and sports wheel speed sensors.
Front and Rear Callipers
Front callipers are twin piston aluminium
construction. The ventilated disc sizes are 300 mm
x 32 mm. The rear brakes have cast iron callipers.
This is because of the hand brake operation using
the rear callipers. The ventilated disc sizes are 288
mm x 20 mm. Each rear calliper has a ball and
ramp park brake mechanism, operating on the
main calliper pads.
D.206.178
D.206.177
FRONT WHEEL SENSOR
REAR WHEEL SENSOR
D.206.178

JAGUARS-TYPEChassis
58
Power Assisted Steering
Introduction
The Jaguar S-TYPE has a variable assist rack and
pinion steering gear and variable rack ratio. The
variable steering rack ratio reduces the number of
turns from lock to lock (2.8) to enhance parking
manoeuvrability whilst maintaining the on-centre
steering precision required at high speed. Full
power assistance is provided for parking. Steering
assistance decreases smoothly at a calibrated rate
to raise driver steering efforts as vehicle speed
increases.
Servicing
There are no carry over parts from XK or XJ Series
vehicles.
The rack is mounted to the rear of cross member
Number 2. The PAS pump is belt driven. A PAS
cooler matrix is located within the radiator
package.
Low PAS pump speeds problems are prevented by
increasing engine speed. A power steering
pressure (PSP) switch senses the demand on the
pump at low engine speeds and increases the
speed to a pre-set minimum.
Hose connections to the pump and the steering
gear are quickfit connectors. The quick connect
tube must be pushed into the existing tube nut
port, along the centreline. The assembly is
complete when the tube end bottoms out in the
port with an audible click/snap. Correct assembly
should be verified by pulling the quickfit tube end.
Servicing of the PAS line involves removal of the
quickfit nut. Replacement PAS lines are supplied
complete with quickfit nut and sealing washer. If
the joint is disturbed it is compulsory to replace
the PTFE sealing ring otherwise leaks are
inevitable. Replacement sealing washers may be
installed with the use of Service tool
D90P-3517-A.
Care must be taken when removing the quickfit
nut from the V6 engine pump as the pulley is
PHENOLIC and is susceptible to damage. The V8
pump installation provides a short jumper tube
from the pump to improve accessibility to the
high-pressure hose connection. The PAS pulley
D.211.247
PA S R AC K
D.211.258
POWER STEERING PRESSURE SWITCH

JAGUARS-TYPEChassis
59
D.211.248
FRONT STEERING ARM requires a Service tool to assist removal. Low-
pressure hose connections are made using
Constant Tension (CT) clamps. Pinion hydraulic
connections are orientated with the bottom
connector low pressure with the longer nut, as
current vehicles.
The PAS fluid is for PAS only; it is not to be used
for transmissions. After manual filling, the system
must be bled using a vacuum pump to remove all
the air from the system to prevent system noises.
Fluid level is checked through a sight window on
the reservoir.
Components replaceable are complete pump,
steering rack, reservoir or hose assembly.
A non-serviceable 10-micron filter is located
within the reservoir to maintain fluid cleanliness
throughout the life of the vehicle. It is essential as
with all Jaguars that the system does not become
contaminated. Cap all ports on disassembly to
prevent contamination ingress. As with current
vehicles, the fluid and reservoir must be renewed
if any major component is replaced i.e. Rack,
pump or cooler.
The road wheels should be set straight ahead and
the steering wheel locked (using service tool
F7LC-3F732-BF) when removal and assembly of
the steering gear or intermediate shaft is required.
This is necessary to prevent damage to the air bag
clock spring within the steering upper column
assembly. The intermediate shaft can only be
assembled to its mating components in one
location. Steering wheel alignment can only be
achieved by adjustment at the tie-rods. A
dimensional check of the steering rack position
may be necessary to verify rack centre.
Steering Column
The steering column assembly is completely new
and uses no parts from previous Jaguar
assemblies:
¥ Construction of the upper column assembly is
based on the use of aluminium extrusions and
castings.
¥ A two shaft lower column assembly is used.
¥ The electronically controlled steering lock, the
steering column lock module (SCLM), is a
physically separate component from the
ignition switch which is fascia mounted.
¥ The dynamic stability control (DSC) steering
wheel position sensor is fitted to the upper
column assembly.
Steering Wheel
The steering wheel consists of a magnesium
armature with a central steel insert. The steering
column and wheel insert are splined with a flat so
that the wheel can only be fitted in one position.
Any misalignment of the steering wheel is
corrected by adjusting the tie rods. The splined
fitting also has a locking taper which requires the
use of a 2 legged puller to remove the wheel.
The steering wheel incorporates the the airbag
module, horn mechanism and the optional cruise
control and audio/phone switches.

JAGUARS-TYPEChassis
60
D.211.255
ELECTRICALLY ADJUSTABLE STEERING COLUMN
Adjustable Column Assembly
The electrically powered upper steering column
assembly provides adjustment for 16û of steering
wheel tilt and 50mm of reach (telescoping
movement) and also features automatic wheel tilt
on entry and exit. A combined joystick and on/off
switch on the side of the column shroud controls
the the tilt and reach movements (see page 106).
Where fitted, the two position memory system
stores settings for steering wheel tilt and reach
together with seat and mirror positions.
The upper column assembly comprises the
following :
¥ The fixed sub-assembly forms a supporting
outer enclosure for the column and consists
of two aluminium extrusions and a steel
stiffening plate bolted together with the lower
extrusion bolted to a lower casting. The
steering column runs in a bearing in the
lower casting which also carries the tilt and
reach drive motors. The complete column
assembly is fixed to the car cross beam via
four bolts to the lower extrusion.¥ The moving section consists of an aluminium
inner housing running on top and bottom ball
bearings within the fixed enclosure and
supporting the tilt head casting. The
telescoping upper section of the steering
column passes through this inner housing and
connects to the steering wheel shaft via a
universal joint located in the tilt head casting.
¥ The tilt and reach motors have integral
gearboxes which directly drive screw
actuators via flexible shafts.
¥ The tilt and reach position measuring
potentiometers, for the driver memorised
positions, are combined in a single
component with linear sliders which are
directly driven by the moving actuators.
¥ Connection to the lower steering column
assembly is via a rag joint (rubber Ôdo-nutÕ
type coupling).
¥ The dynamic stability control (DSC) sensor
ring is located on the column with the sensor
unit fixed to the drive motors (see section on
DSC).
Tilt Motor
Reach MotorRag Joint
SCLM
DSC Sensor Ring
DSC Sensor
Tilt Coupling
Tilt Pivot

JAGUARS-TYPEChassis
61
D.211.253
LOWER STEERING COLUMN
Lower Steering Column Assembly
The adjustable column assembly is connected to
the steering rack via a lower assembly consisting
of two shafts linked by a universal joint. The lower
shaft incorporates a sliding section which is
secured by a pinch bolt on installation. To stabilise
the shaft to shaft joint, the upper of the two shafts
is supported by a bearing assembly where it passes
through the bulkhead.
Gaiter
Bearing and Seal
Slider
¥ Steering column lock module (SCLM) with
splined locking collar on the column.
¥ The retractor box, mounted on the underside
of the lower extrusion, houses the column
wiring harness and connectors with sufficient
cable to allow for column telescopic
movement.