1998 JAGUAR X308 206

P
INPOINT TEST A : BRAKES NOISY
TE
ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
A1

: INSPECT BRAKE PADS
Inspect the condi

tion of the front and rear brake
pads. Check for damage to any anti-squeal shims.
1
Are th
e brake pads OK?
Yes GO to A2
.
No

CLEAN the front brake pads or INSTALL new front brak e pads if necessary. For additional information,
refer toSection 206
-03
Front Disc Brake
. CLEA
N the rear brake pads or INSTALL new rear brake pads
if necessary. For additional information, refer toSection 206
-0
4 Rear Disc Brake
.
Test vehicle for
presence of brake squeal.
A2
: INSPECT BRAKE DISCS
Inspe

ct the brake discs for excessive corrosi
on, wear or disc thickness variation.
1
D
oes excessive corrosion, wear or
disc thickness variation exist?
REFER to Specification
- in t
his section.
Yes INSTALL new front brake discs and brake pads. For additional information, refer toSection 206
-03

Fr

ont Disc Brake
. INSTALL n
ew rear brake discs and brake
pads. For additional information, refer
toSection 206
-0
4 Rear Disc Brake
. TEST
the system for normal operation.
No Vehicle is OK.
P
INPOINT TEST B : VIBRATIO
N WHEN BRAKES ARE APPLIED
TE
ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
B1

: ROAD TEST VEHICLE
R

oad test the vehicle between 40-80 km/h (25-50 mph) without applying brakes.
1
Is th

e vibration present?
Yes TEST for noise vibration and harshness. REPEAT road test if necessary.
No GO to B2
. .

B2

: CHECK FOR BRAKE VIBRATION
R

oad test the vehicle between 40-80 km/h (25-50
mph) with light and medium application on the
brake pedal.
1
Is a vibration
present?
Yes If the vibration is from the front of the vehicle GO to B3
. If
the vibration is
from the rear of the
vehicle or can not be di agnosed between front or rear of the vehicle GO to B6
.
No

Vehicle is OK.
B3: CHECK
THE SUSPENSION
AND STEERING COMPONENTS
Chec
k the condition of the front susp
ension bushes and ball joints
REFER to Section 204
-01
Front Suspension
.
Chec
k the condition of the steering linkage components
REFER to Section 211
-0
2 Power Steering
/

211
-0
3 Steering Linkage
.
1
D

o any of the front suspension components or steering comp
onents require replacement?
Yes INSTALL new components as necessary
REFER to Section 204
-01
Front Suspension
/

211
-0
2 Power Steering
/

211
-0
3 Steering Linkage
.
R
oad test the vehicle between 40-80 km/h (25-50
mph) with light and medium application on the
brake pedal. If vibr ation still exists GO to B4
.
No

GO to B4
.
B4: CHECK
THE FRONT BRAKE PA
DS AND FRONT BRAKE DISCS
Chec
k the condition of the front br
ake pads and front brake discs.
1
D
oes excessive brake disc runout or br
ake disc thickness variation exist?

REFE
R to
Specification
- /
F r
ont Brake Disc Runout Check
- V
eh
icles With: Brembo Brakes
/

F
ront Brake Disc Runout Check
- V
e
hicles Without: Brembo Brakes

in this
section.
Yes GO to B5
.
No
GO to B6
.
B5: CHECK VEHICLE
FOR A HISTORY OF BRAKE VIBRATION PROBLEMS
Chec
k to se
e if the vehicle has recently been
repaired for brake vibration problems by the
installation of new front brake discs and pads.
1
Has vehicl
e has recently been repaired for brake vibrat
ion problems by the installation of new front brake
discs and pads.
Yes INSTALL new front wheel hubs
REFER to Section 204
-01 Fron
t Suspension
.
INST ALL new fr
ont brake disc
s and front brake pads
REFER to Section 206
-03 Fr
ont Disc Brake
.
TEST the system for normal
operation.
No INSTALL front brake discs and front brake pads
REFER to Section 206
-03 Fr
ont Disc Brake
.
CHECK for excessiv
e brake disc runout
REFER to Front Brake Disc Runout Check
- Veh
icles With: Brembo Brakes
/

F
ront Brake Disc Runout Check
- V
e
hicles Without: Brembo Brakes

in this
section.
If excessive brake disc runout exis ts INSTALL new front wheel hubs
REFER to Section 204
-01 Fron
t Suspension
.
TEST the system for normal
operation.
B
6:
CHECK THE REAR BRAKE PADS AND REAR BRAKE DISCS
Chec
k
the condition of the rear brake pads and rear brake discs.
1
D
o
es excessive brake disc runout or br
ake disc thickness variation exist?
REFER to Specification
- /
Rear B
rake Disc Runout Check
- Ve
hicles Without: Brembo Brakes
/
Rear
Brake Disc Runout Check
- Veh
icles With: Brembo Brakes
in this
section.
Yes INSTALL rear brake discs and rear brake pads
REFER to Section 206
-04
Rear Disc Brake
.
CHECK for excessiv
e brake disc runout.
REFER to Rear Brake Disc Runout Check
- Veh
icles With: Brembo Brakes
/

Rear
Brake Disc Runout Check
- V
e
hicles Without: Brembo Brakes

in this
section.
If excessive brake disc runout exists INSTALL ne w rear wheel hubs. TEST the system for normal
operation.
No REPEAT road test and re-check for a vi bration concern. If vibration exists GO to B3
.
PINPOINT TEST
C : THE BRAKES PULL OR DRIFT
TE
S
T
CONDITIONS
D E
TAILS/RESULTS/ACTIONS
C1
:
ROAD TEST VEHICLE
Road test th
e veh
icle and apply the brake pedal.
1
D
o
es the vehicle pull or drift?
Yes GO to C2
.
No
Vehicle is OK.

C2:
INS
PECT TIRE PRESSURE
Check f
or ex
cessive tire wear
or incorrect pressures.
1
Are the ti
res at the correct pressure and in good condition?
Yes GO to C3
.
No
AD
JUST the tire pressures or IN
STALL new tires if excessively wo rn. TEST the system for normal
operation.
C3 : CH
ECK CALIPERS
Check the fr
on
t caliper pistons for binding, leakin
g or sticking. For additional information, refer
toSection 206
-03 Fr
ont Disc Brake
. Check the rear cal
i
per pistons for
binding, leaking or sticking. For
additional information, refer toSection 206
-04
Rear Disc Brake
.
1

Do t
he disc brake caliper pistons
and pins bind, leak or stick?
Yes INSTALL new calipers as necessary. TE ST the system for normal operation.
No GO to C4
.
C4: INSPECT BR
AKE DISCS
Check the brake discs fo

r excess
ive damage, thickness variatio n or runout. For additional
information, refer to General Procedures in this section.
1
D
oes excessive damage or runout exist?
Yes INSTALL new brake discs and brak e pads as necessary. TEST the system for normal operation.
No GO to C5
.
C5: INSPECT THE FRONT HU
B AND WHEEL BEARING ASSEMBLY
Check the fr

ont hub and wheel bearing assembly.
For additional information, refer toSection 204
-00

Su

spension System
- General
Information
. 1
Are th

e wheel bearings OK?
Yes GO to C6
.
No

INSTALL new wheel bearings. For additional inform ation, refer toSection 204
-01
Front Suspension
.
TEST the system
for normal operation.
C

6: CHECK SUSPENSION BUSHES AND BALL JOINTS.
Chec

k all suspension bu
shes and ball joints.
1
Are th
e suspension bushes and ball joints OK?
Yes Vehicle is OK.
No INSTALL new front suspension bushes and ball joints as required. For additional information, refer
toSection 204
-01
Front Suspension
. INSTALL n
ew rear suspension bush
es and ball joints as required.
For additional informat ion, refer toSection 204
-0
2 Rear Suspension
.
P

INPOINT TEST D : THE PEDAL FEELS SPONGY
TE
ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
D

1: CHECK FOR SPONGY PEDAL (ENGINE OFF)
Check f

or a firm brake pedal.
1
Is th

e brake pedal effort an
d brake pedal travel normal?
Yes Vehicle is OK.
No GO to D2
.
D2:
CHECK BRAKE PEDAL RESERVE (ENGINE OFF)
Pump th

e brake pedal 10 times and
hold on the final application.
1
Does th
e brake pedal feel fi
rm on final application?
Yes GO to D3
.
No

BLEED the brake system. For additional information, re fer to General Procedures in this section. TEST
the system for normal operation.
D3:
CHECK BRAKE PEDAL RESERVE (ENGINE ON)
Engine is

idle.
1
Apply the brake pedal ligh

tl
y three or four times.
2
W
ait 15 seconds for the vacuum to recover.
3
Push down on

the brake pedal until it stops moving
downward or an increased resistance to the brake
pedal travel occurs.
4
Hol
d the brake pedal in the applied position while increasing the engine speed to 2000 revs/min.
5
Re

lease the accelerator pedal.
6
Does th

e brake pedal move downward as
the engine speed returns to idle?
Yes GO to D4
.
No

CHECK the vacuum to brake booster. For additional information, refer toSection 206
-0
7 Power Brake
Actuation.

Are th
ere any external brake system leaks?
Yes REPAIR as necessary. ADD fluid and BLEED the brak e system. For additional information, refer to
General Procedures in this section. TEST the system for normal operation.
No GO to F3
.
F
3: CARRY OUT A BRAKE MASTER CYLINDER BYPASS TEST
Te

st for brake master cylinder bypass condition. Re
fer to Brake Master Cylinder Component Test in
this section.
1
A
re any concerns found?
Yes INSTALL a new brake master cylinder, ADD flui d and BLEED the brake system. For additional
information, refer to General Proc edures in this section. TEST the system for normal operation.
No System is OK.
PINPO
INT TEST G : EXCESSIVE BRAKE PEDAL EFFORT
TE
ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
G1

: CHECK BRAKE PADS
Check the brake pads for wear, contamin

atio
n, correct installation, damage and type.
1
A
re any concerns found?
Yes INSTALL the front brake pads correctly or INSTALL ne w front brake pads if necessary. For additional
information, refer toSection 206
-03
Front Disc Brake
. INSTALL the
rear brake pads correctly or
INSTALL new rear brake pads if necessary. For additional information, refer toSection 206
-04
Rear
Di

sc Brake
. REPEAT road test.
No

GO to G2
.
G2:
CHECK VACUUM
Di

sconnect the vacuum booster hose from the booster.
1
Conne

ct a vacuum/pressure tester to the vacuum hose.
2
Ru

n the engine at normal operating temperature.
3
Re

cord the vacuum reading.
4
Is

the reading 40.5kPa (1
2 in-Hg) or greater?
Yes GO to G3
.
No

LOCATE and REPAIR the source of low vacuum . TEST the system for normal operation.
G3
: INSPECT SYSTEM
Swi

tch the engine off.
1
Re

connect the vacuum hose.
2
Inspect th

e brake booster, rubber grommet, and al
l vacuum plumbing for cracks, holes, damaged
connections, or missing clamps.
3
Pump th
e brake pedal several time
s to exhaust the vacuum. Push down on the brake pedal and hold.
4
Does th
e brake pedal move down
when the engine is started?
Yes Vacuum system is OK.
No GO to G4
.
G4
: CHECK POWER BRAKE BOOSTER VALVE
Check the brake booster valve. For
add
itional information, refer to
Brake Booster in this section.
1
Is th
e power brake booster valve OK?
Yes CHECK the brake booster. Fo r additional information, refer to Brak e Booster in this section. INSTALL a
new brake booster if necessary. TEST the system for normal operation.
No INSTALL a new brake booster valve. TEST the system for normal operation.
P
INPOINT TEST H : BRAKE LOCKUP
DURING LIGHT BRAKE PEDAL FORCE
TE
ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
H1

: TEST BRAKE LOCKUP

Road test the veh
icle and a
pply the brake pe dal lightly.
1
Do th
e brakes lockup?
Yes GO to H2
.
No
Vehicle is OK.
H2: INSPECT BRAKE PADS
Inspect brake pads for con
t
amination,
correct installation , damage and type.
1
Ar
e any concerns found?
Yes CHECK the front brake pads. For additi onal information, refer toSection 206
-03 Fr
ont Disc Brake
.
CHECK
the rear brake pads. For additi
onal information, refer toSection 206
-04
Rear Disc Brake
.
INST ALL new brake pads as ne ce
ssary. REPEAT
road test.
No GO to H3
.
H3: INSPECT BRAKE CALI
PERS
Inspect brake cali
pers for bindi
ng, leaking or sticking.
1
A
r
e any concerns found?
Yes CHECK the front brake calipers. For addi tional information, refer toSection 206
-03 Fr
ont Disc Brake
.
CHECK
the rear brake calipers. For addi
tional information, refer toSection 206
-04
Rear Disc Brake
.
IN ST
ALL the brake calipers correctly or INSTALL new
brake calipers as necessary. TEST the system for
normal operation. REPEAT road test if necessary.
No Vehicle is OK.
PI
NPOINT TEST I : BRAKES DRAG
TE
S
T
CONDITIONS
D E
TAILS/RESULTS/ACTIONS
I1
:
ROAD TEST VEHICLE
Ro
ad t
est the vehicle
and apply the brakes.
1
Are the brakes
functioning correctly?
Yes Vehicle is OK.
No GO to I2
.
I2
: CHECK CALIPERS
Check the fr
on
t caliper pistons for binding, leakin
g or sticking. For additional information, refer
toSection 206
-03 Fr
ont Disc Brake
. Check the rear cal
i
per pistons for
binding, leaking or sticking. For
additional information, refer toSection 206
-04
Rear Disc Brake
.
1
Do t
h
e disc brake caliper pistons
and pins bind, leak or stick?
Yes INSPECT the brake calipers and pa rking brake cables. INSTALL new co mponents as necessary. Road
test vehicle.
No GO to I3
.
I3
: CHECK BRAKE BOOSTER
Check the brake booster con
n
ecting rod alignment
and travel. For additional information, refer
toSection 206
-0 7
Power Brake Actuation
. 1
Is the co
nnecti
ng rod OK?
Yes Vehicle is OK.
No INSTALL a new brake booster. For addi tional information, refer toSection 206
-07
Power Brake
Actuation. TEST
the system for
normal operation.
PINPO
I
NT TEST J : EXCESSIVE/ERRATIC BRAKE PEDAL TRAVEL
TE
S
T
CONDITIONS
D E
TAILS/RESULTS/ACTIONS
J
1
: TEST ON ROUGH ROAD
R
oad test the vehi
cle on rough road conditions.
1
Apply the brakes slowly. 2
Is th
e brake pedal ef
fort an
d brake pedal travel normal?

Yes

Vehicle is OK.
No GO to J2
.
J
2: CHECK BRAKE FLUID LEVEL
Check the brake master cyli

nder reservoir fluid level.
1
Is the fl

uid level OK?
Yes GO to J3
.
No

CHECK brake master cylinder reservoir sealing points. For additional information, refer to Brake
Master Cylinder in this section. ADD brake fl uid and BLEED the brake system. For additional
information, refer to General Proc edures in this section. TEST the system for normal operation.
REPEAT road test if necessary.
J
3: CHECK BRAKE PEDAL RESERVE
Engine is

idle.
1
Apply the brake pedal ligh

tl
y three or four times.
2
W
ait 15 seconds for the vacuum to replenish.
3
Push down on

the brake pedal until it stops moving
downward or an increased resistance to the brake
pedal travel occurs.
4
Hol
d the brake pedal in the applied position while increasing the engine speed to 2000 revs/min.
5
Re

lease the accelerator pedal.
6
Does th

e brake pedal move downward as
the engine speed returns to idle?
Yes GO to J4
.
No

CHECK the vacuum to the brake booster. Fo r additional information, refer toSection 206
-0
7 Power
Brake Ac

tuation
.
J

4: CHECK THE FRONT HUB AND BEARING ASSEMBLY
Check the fr

ont hub and bearing assembly. Fo
r additional information, refer toSection 204
-01
Front
Suspe

nsion
. 1
Are th

e front wheel bearings loose?
Yes INSTALL a new front wheel bearin g if damaged. For additional information, refer toSection 204
-01

F

ront Suspension
. TEST
the system for normal operation.
No CHECK the front brake discs for thickness variances. For additional information, refer to General
Procedures in this section.
PINPO
INT TEST K : SLOW OR INCOMPLETE BRAKE PEDAL RETURN
TE
ST
CONDITIONS
D
ETAILS/RESULTS/ACTIONS
K1: C

HECK FOR BRAKE PEDAL RETURN
Ru

n the engine at fast idle while
making several brake applications.
1
Pull the
brake pedal rearward with approximately 44.5 N (10lb) force.
2
Relea

se the brake pedal and measure
the distance to the toe board.
3
Make a hard brake
application.
4
Relea

se the brake pedal and measure the brake
pedal to toe board distance. The brake pedal
should return to its original position.
5
Does th
e brake pedal return
to its original position?
Yes Vehicle is OK.
No GO to K2
.
K
2: CHECK FOR BRAKE PEDAL BINDING
Check the brake pedal to make
s
ure it is operating freely.
1
Is th

e brake pedal operating freely?
Yes INSTALL a new brake booster. For addi tional information, refer toSection 206
-0
7 Power Brake
Actuation. TEST

the system for normal operation.
No REPAIR or INSTALL new brake pedal. TE ST the system for normal operation.

Brake System - Gener
al Information - Front Brake Disc Runout
CheckVehicles With: Standard Brakes
Gen e
ral Procedures
S
p
ecial Tool(s)

Dial Test Indicator
G
auge and Stand.
1. Raise front of vehicle and support on stands. Refer to section
100-02.
2. Remove wheel.

3. CAUT
ION: Tie caliper housing aside. Do not allow the
caliper housing to hang on the hydraulic hose, as this will damage
the hose.
Remove caliper housing from caliper carrier.
1. Remove anti-rattle spring.
2. Remove dust covers.
3. Remove guide pins.
Remove an
d tie caliper housing aside.
4.
Make sure that wheel
bearing en
d-float is correct. Refer to
specification section 204-01.

5. Measure brake d
isc run-out.
Inst
al
l brake disc to hub and secure with all wheel nuts,
tighten wheel nuts to 20 Nm in a diagonal sequence.
Posi
tion the gauge so that the pointer contacts the disc,
10 mm from its outer edge.
Slo w
ly rotate the disc one revolution, the disc run-out
must not exceed the specification. Refer to Specification
Section 206-03.
6. If the brake disc run-out exceeds specification, reposition the
brake disc on the hub and re peat the above procedure.
Continue repositioning the brake di sc until the run-out is within
specification.
7. If the brake disc run-out still exceeds specification, check the
hub face run-out.
8. Remove brake disc. Refer to procedure 70.10.12.
9. Measure hub face run-out.
Posi
tion the gauge so that the pointer contacts the hub
face.
Slo w
ly rotate the hub one revolution, the hub run-out

R
emove and tie caliper aside.
5. Make sure that wheel bearing end-float is within specification. Refer to specification section <<204-01>>.
6.
Measure brake disc run-out.
1. Install brake disc to hub and secure with all wheel nuts, tighten wheel nuts to 20 Nm in a diagonal sequence.
2. Position the gauge so that the pointer contacts the disc, between the disc's outer drill holes and the disc's outer edge.
 Slowly rotate the disc one revolution, the disc run-out must not exceed the specification. Refer to
Specification Section <<206-03>>.
7. If the brake disc run-out exceeds specification, reposition the brake disc on the hub and repeat the above
procedure. Continue repositioning the brake disc until the run-out is within specification.
8. If the brake disc run-out still exceeds specification, check the hub face run-out.
9. Remove brake disc.