change wheel JAGUAR X308 1998 2.G Workshop Manual

General Information - Terminology Glossary

Description an
d Operation

This glossary of terms is intended to cover emissions-related (to SAE J 1930) term inology, and other abbreviations that may
be used in this manual.
The required term may be looked-up in th e left-hand column, and subsequent columns give the standard acronym, unit or
abbreviation, and definition.
Te rm
(s)
Acr
ony
m /
Unit /
Abbreviation
De fi
nition
A
Accel
e
rator Pedal
AP
Af
ter Botto
m Dead
Center
ABDCEvent occurri ng after
BDC
Af
ter Top Dead CenterATDCEvent occurri ng after
TDC
Ai
rbag /
Supplementary
Restraint System
Airbag, SRSAi rbag restraint system for
dr
iver and front seat passenger
Air Cleane rACL
Air ConditioningA/C
Air Conditioning Con t
rol
Module
A/CCMModule c
ontrolling air conditioning, heating and ventilation
Air Conditioning SignalACSA
i
r conditioning compressor clutch operation is signalled to the ECM which
induces idle speed corrections to co mpensate for engine load changes
Alternating cu
rrent
ac
Ai
r Fuel R
atio
AFRN
omi
nally 14.7 parts air to one part fuel
Ampe
reASI unit of current
Ampere hourAhA current of one ampere
fl
owing for one hour
Anti-Lock Braking SystemABSS
y
stem which prevents wheel lock-up
under braking by sensing lack of
rotation of a wheel(s) and divertin g fluid pressure away from it (them)
ABS Control Mo
dule
ABS CM
ABS /
T
raction Control
Control Module
ABS / T
C CM
Atmosph
e
re
atmU
n
it of pressure (1.01325 bar)
Au
to
matic Stability
Control
ASCA form of vehicle
control
in which the ECM reduces en gine torque to control
wheel-spin
B
Baro me
tric Absolute
Pressure Sensor
BAR OSensor measuring the pressure of surr ou
nding air at any given temperature
and altitude
Bat t
ery positive voltage
B+The posi
ti
ve voltage from a battery or
any circuit connected directly to it
Before Bottom Dead
CenterBBDCEvent occurri ng before BD
C
Before Top Dead

Center
BTD
CEvent (usual ly
ignition) occurring before TDC
Blowe
rBLRDe
vice which supplies a current of air at
moderate pressure, e.g. heater or
A/C blower
Body Processor M
odule
BPMControl modu
le
for body electrical systems, e.g. interior lamps, windshield
wash / wipe control
Bott om D
ead Center
BD
CLowest poin t of piston
travel in a reciprocating engine
Brake hors
epowe
r
bhpEffecti
ve horsepower devel
oped by an
engine or motor, as measured by a
brake applied to its output shaft
Brake Mean Effective
Pres sureBME PThat p
art of the effective
pressure developed in a cyli nder that would result in
a cylinder output equal to the bhp of the engine
Brake On/ O
ff
BOOIn
dic
ates the position of the brake pedal
Br
it
ish Standard
BSStan
dar
d specification issued by the British Standards Institution
Br
it
ish Standard
Automotive
BSAu
BusTopology of a commu n
ication network
Bypass
AirBPAMechanica l
control of throttle bypass air
C
Camshaft Posit
i
on Sensor
CMPSIndi
cat
es camshaft position
Canadian Motor
V
ehicle
CMVSS

Suspension System - General Information - Front Camber and Caster
Adjust
ment
Gen
eral Procedures
• NOTE: Before any work is commenced, th e vehicle must be checked to establish that it conforms to the Jaguar original
specification, e.g. wheels, ti res, tire pressures, etc.
• NOTE: The vehicle must be unladen and the fuel tank full when measuring suspension geometry.

1.
Road test the vehicle to establish the exact nature of the
complaint, e.g. pulling to one side, wander.
2. Measure the suspension geometry, fill in the 'Suspension
Geometry Record Form', and co ntact Jaguar Technical Support
for assistance.
3. Technical Support will give advice on the course of action to be
taken to rectify the problem.
4. Each lower wishbone pivots on and is secured to the front
crossbeam by two fulcrum bolts. A circular eccentric flange
formed under the hexagonal head of each fulcrum bolt, has
raised graduation marks to indicate radial position. A washer
with a 'D' shaped hole locates on a flat on the threaded section
of each bolt. This ensures that the washer rotates with the bolt,
maintaining an eccentric position corresponding with the
flanged head. The outer face of the washer is punch marked,
ensuring correct instal lation with the chamfered face inwards.
This permits the washer to rotate freely in the crossbeam cam
reaction plate during a djustm ent. Each fulcrum bolt and
washer are secured by a self locking nut.
On rotation of the bolt, lateral movement of the eccentric flange
and washer is restricted by the cam plate faces, forcing the bolt
shank to move laterally in the crossbeam slots. Lateral
movement of the bolt shank re sults in corresponding inward
and outward movement of th e wishbone arm, effecting
adjustment of wh eel alignment.
Rotation of the front fulcrum bolt principally adjusts wheel
caster angle, with a small amount of camber angle change.
Adjustment of the rear fulcrum bo lt mainly alters wheel camber
angle with a small amount of caster angle change.
On vehicles with VIN up to 833124, fulcrum bolt eccentric
flanges have raised graduation marks representing 15 degree
increments of bolt rotati on from 0 to 90 degrees.
On vehicles with VIN from 833125, the fulcrum bolt graduation
marks represent bolt shank ho rizontal movement in 1mm
increments from 0 to 3mm.
The upper wishbone and fulcrum shaft are not adjustable and
play no part in steering geometry adjustment.

O
ne locking wheel nut is fitted to each road wheel and can on
ly be removed by using the correctly coded socket. For road
wheels with exposed wheel nuts, each locking wheel nut is provided with a cover, which is removed using the cover removal
tool.
Locking wheel nuts have different coded keyway combinations with corresponding coded sockets. The correct socket, and
cover removal tool are supplied with the vehicle toolkit. Sets of sockets are available to Jaguar dealers.
Temporary Spare Wheel
•
NOTE: When using this type of spare wheel note that:
Speed

must not exceed 80 km/h (50 mph).
The normal ro

ad wheel must be reinstalled as soon as possible.
On

ly one temporary wheel may be installed to the vehicle.
Tracti

on control (where fitted
) must be switched OFF.
In certain markets, the spare wheel supplied with the vehicle is of the temporary-use type, it is narrower than the normal
road wheel and takes up less room in the luggage compartment.
Tire
s
The
radial ply tires shown in the 204-04
Specification Section are recommended by Jaguar to meet the high speed
performance of the vehicle. Only tires of identical specification may be fitted as replacements. Unde r no circumstances must
cross-ply tires be fitted.
Tire Inflation Pressures
Al
l recommended tires, including winter tire
s, must be inflated to the pressures shown in the 204-04 Specification Section.
Inflation pressures must only be checked when the tires are cold.
Tire Replac
ement and Wheel-Interchanging
W
hen renewal of tires is necessary, it is
preferable to fit a complete set. If two replacement tires are fitted (to one axle),
they must be of the same manufacturer and type as those on the other axle.
No attempt must be made to interchange wh eels from the front to the rear or vice-versa, as wear produc es a characteristic
pattern on each tire depending upon its po sition on the vehicle. If this position is changed after wear has occurred, the
performance of the tire w ill be adversely affected.
It should be remembered that new tires must be balanced befo re installing to the vehicle.
Win
ter Tires
•
NOTE: Speed must not exceed 210 km/h (131 mph) when winter tires are installed.
Jaguar recommended winter tires as specified in 204-04 Specification Section must only be fitted in complete four-wheel
sets of the same type and size.
Snow Chains and Spike Spider Traction System

Jagu
ar recommended snow chains, must on
ly be installed when using 16 inch wheels with 255/60 R16 winter tires.
• NOTE: When using snow chains or the spike spider traction system, note that:
Snow ch
ains and the spike spider
traction system must only be fitted to the rear wheels.
O
nly Jaguar recommended snow chains and spik
e spider traction system must be used.
The m
aximum permissible speed with winter tires and snow chains or the spike spider traction system fitted is 48
km/h (30 mph).
Tracti
on control (where fitted) must be
switched OFF when using snow chains or the spike spider traction system.

WHE
N CHANGING A WHEEL, ENSURE THAT THE VEHICLE CANNOT MOVE. ALWAYS APPLY THE PARK BRAKE AND
SELECT TRANSMISSION 'P' POSITION.
NEVER RUN THE ENGINE WITH ONE WHEEL OFF THE GROUND, FOR EXAMPLE, WHEN CHANGING THE WHEEL. THE
VEHICLE COULD MOVE.
TIGHTEN THE WHEEL NUTS TO SPECIFICATION. WHEELS MAY COME LOOSE IF OVER OR UNDER TIGHTENED.
USE WHEELS AND WHEEL NUTS DESI GNED FOR XJ SERIES VEHICLES ONLY. AFTERMARKET WHEELS OR WHEEL
NUTS MAY NOT FIT OR FUNCTION PROPERLY AND COULD CAUSE INJURY OR DAMAGE.
In
spection and Verification
To maximize ti
re performance, inspec
t the tires frequently for signs of:
Unev
en wear.
Incorrect
ti
re pressure.
Wh
ee
l imbalance.
Cuts. Abrasi
ons.

B
u
lges (blister).
Ply s
e
paration.
Embedded objects. Impact damage.
Inspe c
tion should be
more frequent when:
Continuo
us high speed op
eration is required.
Ra
pid or extreme temperatures changes occur.
R
o
ad surfaces are rough.
Roads ar
e littered
with debris.
Tread W
e
ar Indicator
•
NO
TE: Tire condition must comply with prevailing local legislation.
New tires must be installed if the wear in dicators are exposed or if there is severe shoulder wear. Shoulder wear is usually
caused by either excessive camber or toe on tires.
T i
re Vibration Diagnosis
A
tir
e vibration diagnostic procedure always
begins with a road test. The road test and the custom er interview (if available)
will provide much of the information need ed to find the source of vibration.
During the road test, drive the vehicle on a road that is smooth and free of undulations. If vibration is apparent, note and
record the following:
The s p
eed at which the vibration occurs.
W
h
at type of vibration occurs in each
speed range - mechanical or audible.
How the vibrati
on is affected
by changes in the following:
- -engine torque
- -vehicle speed
- -engine speed.
Type of v i
bration - sensitivity:
- - torque sensitive,
- - vehicle speed sensitive,
- - or engine speed sensitive.

W
heels and Tires - Wheel and Tire
Re
moval and Installation
Remov

al
CAUTI
ON: Do not use heat to loosen a seized wheel nut: heat will change the metal's properties and damage wheel
bearing and brake caliper seals.
I
nstallation

1.
NOTE
: Certain Jaguar wheels are fitted wi
th a hexagon wheel
nut cover
R
emove the cover with the plastic spanner supplied with
the spare wheel jacking equipment.

2. Loosen
, but do not
remove wheel nuts.
3. Raise vehicle and support on st ands. Refer to Section 100-02.

4. R
emove wheel and tire assembly.
1. Remove wheel nuts.
2. Remove wheel.
1. CAUTION: Do not allow grease to contaminate the wheel
stud threads and wheel nut to wh eel mating surface, as this may
cause the nuts to loosen.
• NOTE: To prevent the wheel corroding on to the hub, smear a
thin layer of grease onto the hub mounting face and spigot; and
wheel mounting face and spigot hole.

The
Nivomat ride levelling system improves ride quality by al
lowing the use of softer road springs, while controlling the
effects on the suspension of a fully laden vehicle. The system uses special rear dampers in place of the normal units. There
are no other components in th e system. The ride levelling system is comple tely automatic, requiring no input from the
driver.
Ride levelling may be specified as an opti on on certain models; it is not available in north American markets. Ride levelling
and adaptive damping are mu tually exclusive options.
The Nivomat damper:
Su
pplements the load-carrying capacity of th
e road springs at high vehicle loads.
Uses road inputs to the
suspension to power the levelling function.
De

tects suspension height dire
ctly from road wheel travel.
Provi
des load-dependent spring rates; the ac
cumulator gas pressure increases with load.
Pr
ovides load-dependent damping; the fluid pressure increases with load.
Op

eration
F
ollowing an increase in vehicle loading,
the dampers adapt to maintain the height of the vehicle within its design range.
The system uses road inputs to the suspension to power the levelling action, and requires up to approximately two
kilometers of travel, following a change in load, to complete the process.
Normal movement of the suspension caus es a pumping action to occur within the damper, as a result of extension and
compression of the pump rod in the pump chamber. Hydraulic fluid is pumped from the pump cham ber into a high pressure
gas accumulator. The increase in gas pressure augments the force developed between th e vehicle axle and the body,
thereby providing lift.
It
em
De
scription
1Pi

ston rod
2Pum

p chamber
3High

pressure
gas accumulator
4Diaphragm
5Co
ntrol orifice
6Pump rod
7Low pressure gas ch

amber
8Low pressure oil

reservoir


Ride Levelling

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

Vehicl
e wanders from side to

side on the road, when the vehicle is driven straight ahead and the steering wheel is held in a firm position
Incorrect ti re
pressure or
tire size.
CHECK and ADJ
UST the tire pressure. For
additional information,
REFER to Section 204
-0 4
Wheels and Tires
. IN
ST
ALL a new tire as necessary. For
additional information,
REFER to Section 204
-0 4
Wheels and Tires
.
Vehi
cl
e is unevenly or
excessively loaded.
A D
JUST the load evenly.
Loose/worn ti
e-
rods.
INST
ALL a ne
w tie-rod
end. For additional
information,
REFER to Section 211
-0 3
Steering Linkage
.
Steeri
ng gear bolts loose
o
r damaged.
TIGHTE
N or INSTALL
new bolts.
Loose or worn suspensi
on
ball jo
int(s).
INST
ALL a ne
w suspension ball joint
assembly. For additional information,
REFER to Section 204
-01 Fron
t Suspension
.
Steeri
ng column uni
versal
joint pinch bolt loose.
TI G
HTEN the steering column universal joint

pinch bolt. For additi onal information,
REFER to Section 211
-0 4
Steering Column
.
Incorre
ct
toe adjustment.

ADJUS
T as necessary. For additional
information,
REFER to Section 204
-00 Sus
pension
Sy
ste
m
- General

Information
.
Loose or worn rear
susp
ension.
TIGHTEN
loose, or IN
STALL new rear
suspension components. For additional information,
REFER to Section 204
-0 2
Rear Suspension
.
Vehicle t
e
nds to pull to one
side when driven on a level surface
Incorrect ti
re pressure.
Incorrect
ti
re size or
different tire/tread type.
Uneven tire wear
CHECK and ADJ
UST the tire pressure. For
additional information,
REFER to Section 204
-0 4
Wheels and Tires
. IN
ST
ALL a new tire as necessary. For
additional information,
REFER to Section 204
-04
Wheels and Tires
.
Vehicl

e is unevenly loaded
or overloaded.
Adjust the load
.
Incorre
ct
toe adjustment.

ADJUS
T as necessary. For additional
information,
REFER to Section 204
-00 Sus
pension
Sy
ste
m
- General

Information
.
Dam
a
ged front suspension

components.
I N
STALL new front suspension components
as necessary. For addi tional information,
REFER to Section 204
-01 Fron
t Suspension
.
Damaged rear
suspen
sion
components.
INST ALL ne
w rear suspension components
as necessary. For addi tional information,
REFER to Section 204
-0 2
Rear Suspension
.
Steeri
ng gear val
ve effort
out of balance.
SHIF T the
transmission into NEUTRAL while
driving at no more than 30 miles/hour (50 km/h) and turn the ignition to position I
(engine OFF-coasting). If the vehicle does
not pull with the engine off, INSTALL a new steering gear. For additional information,
REF E
R to Section 211
-0
2
Power Steering
. If t
he
vehicle does drift with the engine off,
CROSS SWITCH front wheel assemblies.
If the
vehicle pulls to
the opposite side,
SWITCH wheels that were on the rear to the
same side on the front.
If the v
ehicle pull dire
ction is not changed,
CHECK the front susp ension components
and toe adjustments. For additional information,
REFER to Section 204
-01 Fron
t Suspension
.
Chec
k
the front and rear
brakes for correct operation.
ADJUS
T as necessary. For additional
information,
REFER to Section 206
-0 0
Brake System
-
General Informati on.
Check fo
r bent rear
INST
ALL ne
w rear suspension components

Hiss (Swish)
Hiss or Val
ve Hiss is a high-frequency so
und coming from the steering gear when the system is loaded. It is a rushing or
"swish" noise that doesn't change frequency with RPM. Hiss is the general noise generated by the flow of hydraulic fluid
through restrictions in the steer ing system. Restrictions include the rotary stee ring valve, power steering tubes, connectors,
tuning orifices, etc. Hiss can be air- borne and structure-borne, but the structure-borne path through the steering
intermediate shaft is usually dominant.
Moan (Groan)
Moan is the general structu r
e-borne noise of the steering system. Moan is primarily transmitted to the driver via the body
structure through the pump mount, engine mounts, power steering lines and power steering brackets. On some vehicles,
moan is a load humming noise, often present when the wheel is turned and the system is loaded. It may change frequency
with engine RPM and if the sy stem is loaded or unloaded.
Rack Knock (R
ack Slap)
CAU
T
ION: DO NOT attempt to adjust the stee
ring gear yoke. Failure to follow this instruction will result in the steering
gear warranty to become invalid.
Rack Knock is a rattle sound an d steering wheel vibration caused by separation of the steering gear and pinion while driving
over bumps. It is a structure-borne noise transmitted throug h the intermediate shaft and column. Rack knock can also be
heard as a "thump" or impact noise that occurs with the vehicle stationary when the steering wheel is released from a
loaded position and allowed to return to rest . Noise occurs with the engine on or off.
Rattles
Ra
ttles are noises caused by knocking or hitting with components in the steering system. Steering rattles can occur in the
engine compartment, the suspension, or the passenger compartment . Rattles can be caused by loose parts, movable and
flexible parts, and improper clearances.
Squea k
s/Scrapes
Squeaks/Scrapes are noises due
to fri
ction or component rubbi
ng anywhere in the steering system. Squeaks/Scrapes have
appeared in steering linkages and jo ints, in column components and in co lumn and steering wheel trim parts.
Weep
We
ep is an air-borne noise, occasionally
generated when turning the steering across lock at a constant rate. When present
on a vehicle the noise, once initiated can often be maintained across a large proportion of the available steering movement.
Whistle
Wh
istle is similar to hiss but is louder and of a higher frequency. It is also more
of a pure tone noise than hiss. Whistle is
air-borne and is generated by a high flow rate of hydraulic fluid through a small restriction.
Zip

Zip n
o
ise is the air-borne noise
generated by power steerin g pump cavitation when power steering fluid does not flow freely
through the suction hose from the rese rvoir to the pump. Zip primarily occurs during cold weather at start-up.
Steering System Vibrations and Harshne
ss
Buzz
Buzz is a tactile rotary vi

bration felt in
the steering wheel for slow steering inputs. Buzz can also be called a grinding feel
and it is closely related to grunt and is caused by high system gain with low damping. Buzz is generally excited during
parking manoeuvres with low to medium speed steering input.

2.2. Press and rel e
ase to cycle through radio FM, radio AM,
tape cassette, or CD player. Press and hold for two
seconds to select telephone mode.
3. 3. Decrease the volume of the select ed audio output or telephone.
4. 4. Press and release to select the next pr eset radio station, or the next track on tape or CD. Press and hold for two
seconds to select the next radio station on the waveband upwards, or the next CD loaded in the player, or to
change the side of tape. When in te lephone mode, press and release to scroll up to the next memory location.
Press and hold for two seconds to send and end a call.
Speed Control Switchpa ck

The s p
eed control switchpack is installed to the right of th
e steering wheel center and performs the following functions:
1. 1. Set the desired speed or increase the set speed.
2. 2. Resume the previously set speed.
3. 3. Decrease the set speed.
4. 4. Cancel speed control without erasing the set speed.
Horn and Driver Airbag Location

Ite
m
Par
t
Number
De
scr
iption
1-Se
t
speed or increase speed
2-Re
sum
e
3-De
creas
e speed
4-Cancel
Ite

m
Part
Number
Descr
iption
1-Horn operatin
g pad

The ho
rn operating pad is mounted in the central area of the steering wheel.
2-Driver air bag location