brakes FIAT UNO 1983 Service User Guide

20By connecting a pressurised container to
the master cylinder fluid reservoir, bleeding is
then carried out by simply opening each bleed
screw in turn and allowing the fluid to run out,
rather like turning on a tap, until no air is
visible in the expelled fluid.
21By using this method, the large reserve of
hydraulic fluid provides a safeguard against
air being drawn into the master cylinder
during bleeding which often occurs if the fluid
level in the reservoir is not maintained.
22Pressure bleeding is particularly effective
when bleeding “difficult” systems or when
bleeding the complete system at time of
routine fluid renewal.
All methods
23When bleeding is completed, check and
top up the fluid level in the master cylinder
reservoir.
24Check the feel of the brake pedal. If it
feels at all spongy, air must still be present in
the system and further bleeding is indicated.
Failure to bleed satisfactorily after a
reasonable period of the bleeding operation,
may be due to worn master cylinder seals.
25Discard brake fluid which has been
expelled. lt is almost certain to be
contaminated with moisture, air and dirt
making it unsuitable for further use. Clean
fluid should always be stored in an airtight
container as it absorbs moisture readily
(hygroscopic) which lowers its boiling point
and could affect braking performance under
severe conditions.
13 Vacuum servo unit-
description
A vacuum servo unit is fitted into the brake
hydraulic circuit on 55 and 70 models in series
with the master cylinder, to provide assistance
to the driver when the brake pedal is
depressed. This reduces the effort required by
the driver to operate the brakes under all
braking conditions.
The unit operates by vacuum obtained from
the induction manifold and comprises basically
a booster diaphragm and non-return valve. The
servo unit and hydraulic master cylinder are
connected together so that the servo unit
piston rod acts as the master cylinder pushrod.
The driver’s braking effort is transmitted
through another pushrod to the servo unit
piston and its built-in control system. The servo
unit piston does not fit tightly into the cylinder,
but has a strong diaphragm to keep its edges
in constant contact with the cylinder wall, so
assuring an air tight seal between the two
parts. The forward chamber is held under
vacuum conditions created in the inlet manifold
of the engine and, during periods when the
brake pedal is not in use, the controls open a
passage to the rear chamber so placing it
under vacuum conditions as well. When the
brake pedal is depressed, the vacuum passageto the rear chamber is cut off and the chamber
opened to atmospheric pressure. The
consequent rush of air pushes the servo piston
forward in the vacuum chamber and operates
the main pushrod to the master cylinder.
The controls are designed so that
assistance is given under all conditions and,
when the brakes are not required, vacuum in
the rear chamber is established when the
brake pedal is released. All air from the
atmosphere entering the rear chamber is
passed through a small air filter.
Under normal operating conditions, the
vacuum servo unit is very reliable and does
not require overhaul except at very high
mileages. In this case, it is far better to obtain
a service exchange unit, rather than repair the
original unit.
It is emphasised that the servo unit assists
in reducing the braking effort required at the
foot pedal and in the event of its failure, the
hydraulic braking system is in no way affected
except that the need for higher pressures will
be noticed.
14 Vacuum servo unit-
servicing and testing
1Regularly, check that the vacuum hose
which runs between the servo unit and the
inlet manifold is in good condition and is a
tight fit at both ends.
2If broken or badly clogged, renew the air
filter which is located around the brake pedal
push rod. Access to this is obtained by
disconnecting the pushrod from the
cross-shaft or pedal arm, withdrawing the
pushrod, dust excluding boot and end cap.
3If the new filter is cut diagonally from its
centre hole, future renewal can be carried out
without the need for disconnection of the
pushrod.
4If the efficiency of the servo unit is suspect,
it can be checked out in the following way.
5Run the engine, then switch off the ignition.
Depress the footbrake pedal; the distinctive
in-rush of air into the servo should be clearly
heard. It should be possible to repeat this
operation several times before the vacuum in
the system is exhausted.
6Start the engine and have an assistant
apply the footbrake pedal and hold it down.
Disconnect the vacuuum hose from the servo.
There should not be any in-rush of air into the
servo through the connecting stub. lf there is,
the servo diaphragm is probably faulty. During
this test, expect the engine to idle roughly,
unless the open end of the hose to the inlet
manifold is plugged. Reconnect the hose.
7With the engine off, depress the brake
pedal fully. Start the engine with the brake
pedal still depressed; the pedal should be felt
to go down fractionally.
8If the results of these tests are not
satisfactory, remove the unit and fit a new one
as described in the next Section.
15 Vacuum servo unit-
removal and refitting
3
1Syphon as much fluid as possible out of the
master cylinder reservolr.
2Disconnect electrical leads from the
terminals in the reservoir cap then uncouple
the rigid pipelines from the master cylinder
body. Be prepared to catch leaking fluid and
plug the open ends of the pipelines.
3The master cylinder can be unbolted now
from the servo unit, or detached later when
the complete assembly is withdrawn.
4Working inside the car, disconnect the
servo pushrod from the pedal then remove the
servo mounting nuts.
5Withdraw the servo assembly into the
engine compartment, then remove it to the
bench. lf the master cylinder is still attached,
cover the wings with protective sheeting, in
case brake fluid is spilled during removal.
6Refitting is a reversal of the removal
process, but adjust the pushrod clearance as
described in Section 9. On completion of
refitting, bleed the complete hydraulic system
as described in Section 12. Note: Where the
help of an assistant is available, the servo
pushrod need not be disconnected from the
pedal. The rod is a sliding fit in the servo and
the servo can be simply pulled off the rod.
Refitting without having disconnected the rod
from the pedal can be difficult unless the help
of an assistant is available.
16 Handbrake- adjustment
1
Adjustment is normally automatic, by the
movement of the rear brake shoes on their
automatic adjusters.
However, owing to cable stretch,
supplementary adjustment is occasionally
required at the control lever adjuster nut. The
need for this adjustment is usually indicated
by excessive movement of the control lever
when fully applied.
1The rear brakes should be fully applied
when the handbrake control lever has been
pulled over four or five notches.
2If adjustment is required, release the
8•8 Braking system
16.2 Handbrake adjuster nuts

locknut and turn the adjuster nut on the
handbrake primary rod (photo).
3Raise the rear roadwheels and check that
they turn freely when the handbrake lever is
fully released.
17 Handbrake cable-
renewal
1
1There are two cables, either of which may
be renewed independently
2Disconnect the cable, which is to be renewed,
from the shoe lever at the brake backplate.
3Disconnect the longer cable from the
primary link or rod and release the cable from
its retainers. On later models with a plastic
fuel tank, a cable bracket is moulded into the
side of the tank (photo).4Disconnect the shorter cable from the pivot
lever at the pulley on the rear axle (photo).
5Refit the new cables by reversing the
removal operations and then adjust as
described in the preceding Section.
18 Brake pedal-
removal and refitting
1
1The operations are described in
conjunction with the clutch pedal in Chapter
5, Section 4.
2The brake pedal pushrod will slide out of
the servo unit as the pedal is withdrawn.
19 Stop lamp switch
1
1The brake stop lamp switch is of plunger
type acting on the pedal arm.
2Adjust the position of the switch by turning
the locknuts until the stop lamps illuminate
when the pedal arm is depressed through 1.0
mm (0.039 in).
Braking system 8•9
Fig. 8.13 Handbrake components (Sec 17)
17.4 Handbrake cable pulley17.3 Handbrake cable guide on fuel tank
8
Fault finding - braking system
Excessive pedal travel
m mPads or shoes excessively worn
m mIncorrect pedal or servo pushrod adjustment
m mAutomatic adjusters faulty
m mSeized wheel cylinder or caliper piston
m mMaster cylinder seals worn
Pedal feels spongy or soggy
m
mAir in hydraulic system
m mLow fluid level
m mLoose connections
m mFlexible hose perished
m mDefective wheel cylinder or caliper seal
Pedal feels springy
m
mNew pads or linings not bedded-in
m mMaster cylinder mounting loose
Pedal vibrates when brakes applied
m
mDiscs or drums distorted
m mFriction linings excessively worn
m mLoose backplate or caliper mounting bolts
m mWear in steering or suspension components
Excessive effort required to stop car
m
mWorn or contaminated linings or pads
m mIncorrect grade of lining or pad material
m mServo vacuum hose leaking or disconnected
m mFaulty servo or non-return valve (55 or 70 models)
m mSeized caliper or wheel cylinder piston
m mOne circuit defective on dual circuit hydraulic system
Brakes pull to one side
m
mFriction linings contaminated on one side of car
m mSeized hydraulic piston on one side of car
m mDifferent types of linings fitted on different sides of car, or new
linings on one side only
m mSeized automatic adjuster on one side of car
Brakes drag
m
mHandbrake linkage overadjusted or seized
m mSeized caliper or wheel cylinder piston
Brakes squeal
m
mDrums or discs rusty or damp (temporary fault - no action
necessary)
m mDust or grit in brake drums
m mLinings excessively worn

10 Trailing arm rubber bush-
renewal
3
1A worn trailing arm rubber bush may be
renewed in the following way.
2Raise the rear of the car and support
securely on axle stands placed under the
body side-members or sill jacking points.
3Remove the roadwheels.
4Unscrew and remove both pivot bolts
which hold the forward ends of the trailing
arms to the body brackets.5Pull the trailing arms downward out of the
body brackets.
6A two-legged puller may be used to press
the old bush out and to force the new one in.
Smear the bush with soapy water or brake
fluid to facilitate fitting.
7Reconnect the trailing arms to the body
brackets. Use jacks if necessary to push the
arms upwards into the brackets.
8Tighten the pivot bolts to the specified
torque, but only when the car has been
located with four occupants or the equivalent
plus 40 kg (88 lb) of luggage.11 Rear suspension-
removal and refitting
3
1Raise the rear of the car, support it securely
and remove the rear road wheels.
2Unhook the brake pressure regulating valve
arm tension spring from its bracket.
3Disconnect the handbrake cables from the
brake backplate levers.
4Disconnect the flexible brake hose at its
junction with the rigid pipeline adjacent to the
pressure regulating valve. Cap the open ends
of hose and pipe.
5Support the trailing arms and then
disconnect the shock absorber upper
mountings.
6Unbolt the trailing arm forward end support
brackets from the body, lower the complete
rear suspension and withdraw it from under
the car.
7Refitting is a reversal of removal, but tighten
the trailing arm pivot bolts to the specified
torque only when the car is loaded with four
occupants and 40 kg (88 lb) of luggage
(photo).
8Bleed the brakes as described in Chap-
ter 8.
Suspension 11•5
Fig. 11.9 Removing trailing arm pivot bolt
(Sec 10)
Fig. 11.8 Rear suspension components (Sec 8)
11.7 One side of the rear suspensionFig. 11.11 Handbrake cable and lever at
brake backplate (Sec 11)
Fig. 11.10 Method of renewing trailing arm
bush (Sec 10)
11
1 Trailing arm bracket
2 Axle beam
3 Buffer
4 Shock absorber top mounting
5 Coil spring
6 Shock absorber
7 Stub axle
8 Hub

Braking system................................................................................. 14
Part A: Braking system general
Front brake pads all later models
Part B: Braking system - Turbo ie models
Description
Front disc pads - renewal
Front disc caliper - removal and refitting
Front disc caliper - overhaul
Front brake disc - inspection, renovation or renewal
Rear disc pads - renewal
Rear disc caliper - removal, overhaul and refitting
Rear brake disc - inspection, renovation and renewal
Pressure regulating valve
Brake pedal - removal and refitting
Vacuum servo unit and master cylinder - general
Antiskid system - description
Electrical system.............................................................................. 15
Alternator (999 cc models) - removal and refitting
Alternator (later models) - removal and refitting
Alternator brushes - renewal
Starter motor (999 cc models) - removal and refitting
Starter motor (1301 cc Turbo ie, 1372 cc ie, 1372 cc Turbo ie)
- removal and refitting
Starter motor brushes (later models) - renewal
Fuses - later models
Relays (Turbo ie models) - general
Headlamps - later models
Headlamp beam adjusters for load compensation - later models
Headlamp unit removal - later models
Headlamp dim-dip system - description
Front fog lamps bulb/unit - removal and refitting and beam
adjustment
Horn - relocation
Steering column combination switches (later models) - removal
and refittingInstrument panel (Turbo ie models) - removal and refitting
Facia-mounted switches (1301 cc Turbo ie model) - removal
and refitting
Instrument panel (later models) - removal and refitting
Auxiliary control panel (later models) - removal and refitting
Heater control panel (later models) - removal and refitting
Trip master
Interior roof mounted spotlamp, switch and/or clock - removal
and refitting
Central door locking system
Cigar lighter (later models) - removal and refitting
Electrically operated window switches - removal and refitting
Windscreen wiper motor (later models) - removal and refitting
Windscreen washer reservoir (Turbo) - removal and refitting
Tailgate wiper motor (later models) - removal and refitting
Radio Check control system sensors - description
Check control system sensors - testing
Suspension....................................................................................... 16
Front anti-roll bar - removal and refitting
Suspension strut later models
Bodywork.......................................................................................... 17
Plastic components
Rear view mirrors
Door armrest
Tailgate (Turbo ie model) - component removal and refitting
Radiator grille (1301 cc Turbo ie model) - removal and
refitting
Radiator grille (1372 cc ie and 1372 cc Turbo ie models) -
removal and refitting
Bumpers (1301 cc Turbo ie, 1372 cc ie and 1372 cc Turbo ie
models) - removal and refitting
Rear hinged windows - removal and refitting
Door trim panel (Turbo ie model) - removal and refitting
Supplement: Revisions and information on later models 13•3
13
1 Introduction
Since its introduction in 1983, the FIAT Uno
has had a number of modifications and
improvements including the fitting of a twin
choke carburettor, low profile tyres, tinted
windows and remotely-controlled central door
locking.
The major mechanical change was the
introduction of the FIRE (Fully Integrated
Robotised Engine) on 45 and 45S models to
be followed by a new 1108 cc “FIRE” engine
on the 60S model from 1989 on.
A 1301 cc Turbo ie engine model wasavailable for a short period. This model had a
Bosch LE2 Jetronic electronic fuel injection
(ie) and a turbocharger to give added
performance. To uprate the braking to suit,
disc brakes were fitted to the rear in place of
the original drum type brakes.
A 1372 cc engine model was introduced in
1989. Two versions were initially available. A
Bosch Mono-Jetronic single-point fuel
injection (SPi) system, as found on the 70 SX
model and Bosch L3.1 or L3.2 Jetronic
multi-point fuel injection (MPi) systems were
fitted to Turbo models. L3.2 MPi system
models were equipped with catalytic
converters, to improve exhaust emission. All
fuel injection engines are fitted with electroni-
cally controlled engine management systems.
A new style instrument panel, switchgearand a revised facia layout was introduced in
1989.
During 1992, SPi fuel systems were fitted to
the 999 cc and 1108 cc engines, along with
catalytic converters for improved exhaust
emissions.
Five speed transmissions were introduced
to 999 cc models in 1993.
It is recommended that this Supplement is
always referred to before the main Chapters
of the Manual.
Project vehicles
The vehicles used in the preparation of this
supplement, and appearing in many of the
photographic sequences were a 1986 Uno
45S FIRE, a 1988 1301 cc Uno Turbo ie and a
1991 1372 cc Uno SXie.
Easy,suitable for
novice with little
experienceFairly easy,suitable
for beginner with
some experienceFairly difficult,
suitable for competent
DIY mechanic
Difficult,suitable for
experienced DIY
mechanicVery difficult,
suitable for expert DIY
or professional
Degrees of difficulty
54321

Torque wrench settingsNm lbf ft
Driveshaft flange connecting bolts (Turbo ie) . . . . . . . . . . . . . . . . . . . . . 43 32
Final drive output shaft bearing cover bolts (Turbo ie) . . . . . . . . . . . . . . 24 18
Intermediate shaft support to crankcase (Turbo ie) . . . . . . . . . . . . . . . . 48 35
Braking system (903, 999, 1108, 1116 and 1372 cc)
General
Note:The following items differ, or are additional to those specified in Chapter 8:
Master cylinder bore diameter:
903 cc, 999 cc, 1108 cc and 1116 cc . . . . . . . . . . . . . . . . . . . . . . . . . 19.05 mm
1372 cc ie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20.65 mm
Vacuum servo diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152.4 mm
Hydraulic push rod-to-master cylinder support plate clearance . . . . . . 0.825 to 1.025 mm
Braking system (1301 and 1372 cc Turbo ie)
General
System type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Four-wheel discs, ventilated front, solid rear. Vacuum servo. Pressure
regulating valve on rear brakes
Master cylinder bore diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22.225 mm
Vacuum servo diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177.8 mm
Front disc brakes
Disc diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240.0 mm
Disc thickness - new . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19.9 to 20.1 mm
Disc thickness - minimum (refinishing) . . . . . . . . . . . . . . . . . . . . . . . . . . 18.6 mm
Disc thickness - minimum (wear limit) . . . . . . . . . . . . . . . . . . . . . . . . . . 18.2 mm
Minimum thickness of pad friction material . . . . . . . . . . . . . . . . . . . . . . 1.5 mm
Caliper cylinder diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48.0 mm
Rear disc brakes
Disc diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227.0 mm
Disc thickness - new . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.7 to 10.9 mm
Disc thickness minimum (refinishing):
1301 cc Turbo ie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.7 mm
1372 cc Turbo ie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.35 mm
Disc thickness - minimum (wear limit) . . . . . . . . . . . . . . . . . . . . . . . . . . 9.0 mm
Minimum thickness of pad friction material . . . . . . . . . . . . . . . . . . . . . . 1.5 mm
Caliper cylinder diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34.0 mm
Torque wrench settingsNm lbf ft
Front caliper cylinder housing mounting bolts . . . . . . . . . . . . . . . . . . . . 52 38
Front caliper support bracket bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 38
Front disc fixing bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18
Rear caliper support bracket bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 18
Rear caliper cylinder housing mounting bolts . . . . . . . . . . . . . . . . . . . . 52 38
Electrical system
Battery
Turbo ie engine models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Ah
Fuses (903, 999, 1116, 1299/1301 and 1301 cc Turbo ie)
Fuse No. Rating Circuit
1 7.5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . LH tail, RH front parking, rear number plate, check panel
2 7.5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RH tail, LH front parking, cigar lighting, clock light, heater control
illumination, map reading lamp.
3 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RH headlamp main beam
4 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . LH headlamp main beam and warning light
5 25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Radiator cooling fan, econometer and horns
6 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cigar lighter, courtesy lamps, digital clock, stop-lamp switch, clock
and radio
7 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RH headlamp dipped beam
8 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . LH headlamp dipped beam, rear fog warning lamp and indicator
9 20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Heated rear screen and warning lamp
10 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instrument panel, stop-lamps, direction indicators, reversing lamps
and warning module
11 20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Heater fan, fan control illumination and digital clock
12 20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Windscreen wiper, washer pump and rear screen wiper
13 - . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Spare
14 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hazard warning lamps and indicator
Supplement: Revisions and information on later models 13•15
13

13•18 Supplement: Revisions and information on later models
Every 9000 miles (15 000 km) or
12 months (whichever comes first)
m mCheck the tyre pressures and their condition
(including the spare)
m mWhere a pad wear warning light is fitted, check its
operation
m mCheck the front brake disc pads for excessive wear
m mCheck the underbody condition (fuel and brakes
pipes, exhaust system, hoses, bushes and gaiters)
m mCheck the condition and tension of drivebelts
m mCheck the engine idle speed and CO emissions
m mCheck the EGR system (If fitted)
m mCheck fluid levels (coolant, brake fluid and
windscreen washer)
m mRenew spark plugs (1372 cc Turbo models)
m mRenew the engine oil and oil filter (non-Turbo
models)
m mCheck the HT leads and connections
m mCheck the condition of all coolant, fuel and
hydraulic hoses and connections
Every 18 000 miles (30 000 km) or
24 months (whichever comes first)
In addition to the items listed for 9000 mile (15 000 km) or 12 months
service
m mCheck the rear brake disc pads for wear (where
applicable)
m mCheck/adjust the valve clearances
m mCheck and tighten (if necessary), inlet and exhaust
manifolds
m mCheck the clutch adjustment (cable operated
models)
m mRenew the fuel filter (where applicable)
m mRenew the air cleaner element
m mRenew the spark plugs and check the HT leads
and connections (all models)
m mWhere applicable, have the ignition and injection
systems checked (special equipment needed)
m mRenew coolant
m mRenew brake fluid
Every 28 000 miles (45 000 km) or
36 months (whichever comes first)
In addition to the items listed for 9000 mile (15 000 km) or 12 months
service
m mCheck Lambda (oxygen) sensors operation (special
equipment needed)
m mCheck fuel evaporation system (where fitted)
m mCheck the transmission oil level
m mCheck the condition crankcase ventilation system
Every 37 000 miles (60 000 km) or
48 months (whichever comes first)
In addition to the items listed for 18 000 mile (30 000 km) or
24 months service
m mCheck the condition of the rear brake shoe linings
m mCheck the condition of the timing belt
Every 65 000 miles (105 000 km)
m
mRenew the timing belt
Every 74 500 miles (120 000 km)
m
mRenew the manual transmission oil
Every 250 miles (400 km), weekly or
before a long journey
m mProceed as described for the earlier models at the
start of this manual
Every 6000 miles (10 000 km) or
12 months (whichever comes first)
m mRenew the engine oil and oil filter (Turbo models
only)
3 Routine maintenance- all models from June 1991
The maintenance intervals in this manual are provided with the
assumption that you, not the dealer, will be carrying out the work.
These are the minimum maintenance intervals recommended by us, for
vehicles driven daily. If you wish to keep your vehicle in peak condition
at all times, you may wish to perform some of these procedures more
often. We encourage frequent maintenance, since it enhances the
efficiency, performance and resale value of your vehicle.
If the vehicle is driven in dusty areas, used to tow a trailer, or driven
frequently at slow speeds (idling in traffic) or on short journeys, more
frequent maintenance intervals are recommended.
When the vehicle is new, it should be serviced by an authorised
dealer to preserve the factory warranty.

20When reassembling, pack the joint with
special FIAT Tutela MRM2 lubricant; if this is not
available, use molybdenum disulphide grease.
21The reference groove on the outer track
must be assembled so that it is towards the
final drive when refitted (photo).
22Pack the joint and the inside of the boot
liberally with the specified grease.
23If a new joint is being fitted to the shaft,
make sure that the joint and shaft colour
codes match.
Shaft colour Joint colour
Blue Blue or white
Red Red or white
Right-hand driveshaft damper
weight (1108 cc and
1372 cc ie models) -
removal and refitting
#
24A damper weight is fitted to the longer,
right-hand driveshaft to reduce vibration (photo).25It should not be necessary to remove the
damper weight unless the driveshaft is to be
renewed, or the weight has been damaged.
26The weight is in two halves, and can be
removed by simply unscrewing the two clamp
bolts securing the two halves to the
driveshaft. Note that the weight locates on a
rubber mounting which is split along its
length, and can simply be pulled from the
driveshaft for renewal if necessary.
27Refitting is a reversal of removal, but
ensure that the damper weight is positioned
exactly as shown in Fig. 13.101.
14 Braking system
PART A: BRAKING
SYSTEM - GENERAL
Front brake pads - all later
models
1The front brake pads have modified
anti-vibration plates and a wire spring fitted to
prevent them from vibrating and knocking in
operation. 2On some models the clip securing the disc
pad locking block is located on the inboard
end, rather than the outer end (shown in
Chapter 8). To ensure correct reassembly,
check the location of the original block
retaining clip before dismantling the brake
unit. The alternative fixing arrangement is
shown in the accompanying photos, in this
instance on a 1372 cc ie model (photos).
PART B: BRAKING SYSTEM
- TURBO IE MODELS
Description
1Disc brakes are fitted to all four wheels on
the Turbo ie models. The front disc brakes are
of different design from those used on other
models, in that the wear in the pads can be
checked without the need to remove the
caliper cylinder housing.
Front disc pads - renewalª
2Raise the front of the car and remove the
roadwheels.
3Check the thickness of the friction material
on the pads through the aperture in the caliper
cylinder body. If the thickness of the material
is 1.5 mm or less, then the pads on both sides
must be renewed (photo).
13•100 Supplement: Revisions and information on later models
14B.3 Front disc pads (arrowed) on Turbo
ie model14A.2B Front brake locking block
orientation with inboard retaining clip14A.2A Front brake pad locking block is
secured by a clip on the inboard end of the
brake unit on certain models
Fig. 13.101 Correct position of driveshaft damper weight on 1108 cc and 1372 cc ie
models (Sec 13)
Dimensions in mm
13.24 Right-hand driveshaft damper weight
13.21 Outer track reference groove

Wiring diagrams 14•21
14
Component key for wiring diagrams 30 to 52 (continued)
Note: Not all the items listed will be fitted to all models
No Description
111 Push button on left front pillar for
centre courtesy light
112 Front electric windows switch panel,
driver’s side
113 Join between dashboard cable and
adjustable map reading light cables
114 Join with left front electric window
cables
115 Join between dashboard cable and
rear cables
116 Join between rear cable and courtesy
light cables
117 Left front speaker
118 Handbrake ‘on’ switch
119 Centre courtesy light bulb
119A Adjustable map reading light on rear
view mirror
120 Right front electric window motor
121 Right front central locking geared
motor
122 Switch signalling right front door ajar
123 Push button on right front pillar for
centre courtesy light
124 Electric windows control panel,
passenger side
125 Fuel level gauge
126 Join with right front electric window
cables
127 Join between engine cable and
dashboard cables
128 Right front speaker
129 Left rear light cluster
130 Join between rear cable and luggage
compartment courtesy light
131 Windscreen washer pump wiring join
132 Rear screen washer pump wiring join
133 Left rear earth
134 Rear screen wiper motor
135 Electric fuel pump
136 Rear number plate lamp
137 Heated rear screen
138 Right rear light cluster
139 Rear foglamp go-ahead switch
140 Join between front cable and antiskid
brakes cables
141 Join between front cable and antiskid
brakes cables
142 25 A fuse for antiskid brakes
143 Antiskid braking system control unit
144 Left modulator for antiskid brakes
145 Right modulator for antiskid brakes
146 Sensor on left front wheel
147 Sensor on right front wheel
148 10A fuse for antiskid braking system
149 Vacuum switch for antiskid braking
system
150 Antiskid braking system engagement
relay
151 Antiskid braking system failure
signalling switch
152 Digiplex electronic ignition control
unitNo Description
153 Bosch SPi Mono-Jetronic injection
system control unit
155 Join between engine cable and
injection cables
156 Join between engine cable and rear
cables for SPi system
157 Idle adjustment actuator
158 Throttle position switch
159 Injector current restriction resistor
(SPi)
162 Engine cut-out solenoid
163 Idle cut-out solenoid valve
168 Tachometer electro-magnetic sensor
169 Automatic heater control unit
170 Heater fan
171 Outside temperature sensor
172 Mixed air temperature sensor
173 Air mixture flap electrical control
motor
174 Diagnostic socket for automatic
heater
175 Connector block
176 Connector block
177 Join with cables for automatic heater
178 Radiator coolant circulation solenoid
valve
179 Automatic heater unit:
A Temperature control potentiometer
B Fan speed control potentiometer
C Heater controls light bulbs
D Ideogram signalling automatic
function engaged
E Automatic function engaged
switch
180 Horn
181 Check Panel:
A Insufficient engine oil level warning
light
B Insufficient coolant level warning
light
C Failure with side lights/rear
foglamp/rear number
plate light/braking lights warning light
D Insufficient brake fluid level
warning light
E Door ajar warning light
F Brake pad wear warning light
182 Earth on dashboard
183 Join with cables for central locking
184 Join with cables for central locking
185 Left rear central locking geared motor
186 Right rear central locking geared
motor
187 Contact on choke lever
188 Resistor for inlet manifold heating
189 Pre-heating thermal switch
191 Heated Lambda sensor
192 Lambda sensor protective fuse
193 Silicon diode
194 Join between front cable and injection
cable
197 Connector blockNo Description
198 Rear cable join
199 Insufficient engine oil level sensor
200 Insufficient coolant level sensor
201 Switch signalling left rear door ajar
202 Switch signalling right rear door ajar
203 Switch on gear selector
204 Light for gear selector panel signalling
gear engaged
205 Parking signal not on
206 Connector block
207 Join in engine compartment with
injection cables
208 Petrol vapour cut out-solenoid valve
209 Petrol vapour cut out-solenoid valve
210 Airflow meter
211 Speedometer relay
212 LE2 Jetronic electronic injection
control unit
213 Connector block
214 Connector block
215 Connector block
216 Ignition cable join
217 Join between front cable and
emission control cable
218 Join between front cable and battery
cable
219 Injection system air temperature
sensor
220 Ignition control unit relay feed
225 Front cable join
226 Front cable join
227 Dim-dip circuit cut out switch
228 Dim-dip circuit resistance
229 Dim-dip circuit 7.5 A protective fuse
230 Driver’s side seat heated pad
231 Driver’s seat backrest heated pad
232 10 A protective fuse for driver’s seat
heated pads
233 Foglamps go-ahead switch
234 Driving lights cut out switch
235 Dipped headlamps relay
236 Main beam headlamps relay
237 Join between engine cable and
dashboard cables
Wire colour codes
A Light blue
B White
C Orange
G Yellow
H Grey
L Blue
M Brown
N Black
R Red
S Pink
V Green
Z Violet
Example of two-colour wire:
BN (White/Black)

Engine cuts out suddenly –
ignition fault
m mLoose or disconnected LT wires
m mWet HT leads or distributor cap (after
traversing water splash)
m mCoil failure (check for spark)
m mOther ignition fault (see Chapter 4)
Engine misfires before cutting out
– fuel fault
m mFuel tank empty
m mFuel pump defective or filter blocked
(check for delivery)
m mFuel tank filler vent blocked (suction will be
evident on releasing cap)
m mCarburettor needle valve sticking
m mCarburettor jets blocked (fuel contami-
nated)
m mOther fuel system fault (see Chapter 3)
Engine cuts out – other causes
m
mSerious overheating
m mMajor mechanical failure (eg camshaft
drive)
Ignition (no-charge) warning light
illuminated
m mSlack or broken drivebelt — retension or
renew (Chapter 9)
Ignition warning light not
illuminated
m mCoolant loss due to internal or external
leakage (see Chapter 2)
m mThermostat defective
m mLow oil level
m mBrakes binding
m mRadiator clogged externally or internally
m mElectric cooling fan not operating correctly
m mEngine waterways clogged
m mIgnition timing incorrect or automatic
advance malfunctioning
m mMixture too weak
Note: Do not add cold water to an overheated
engine or damage may result
Note: Low oil pressure in a high-mileage
engine at tickover is not necessarily a cause
for concern. Sudden pressure loss at speed is
far more significant. In any event check the
gauge or warning light sender before
condemning the engine.
Gauge reads low or warning light
illuminated with engine running
m mOil level low or incorrect grade
m mDefective gauge or sender unit m mWire to sender unit earthed
m mEngine overheating
m mOil filter clogged or bypass valve defective
m mOil pressure relief valve defective
m mOil pick-up strainer clogged
m mOil pump worn or mountings loose
m mWorn main or big-end bearings
Pre-ignition (pinking) on
acceleration
m mIncorrect grade of fuel
m mIgnition timing incorrect
m mDistributor faulty or worn
m mWorn or maladjusted carburettor
m mExcessive carbon build-up in engine
Whistling or wheezing noises
m
mLeaking vacuum hose
m mLeaking carburettor or manifold gasket
m mBlowing head gasket
Tapping or rattling
m
mIncorrect valve clearances (where appli-
cable)
m mWorn valve gear
m mWorn timing chain or belt
m mBroken piston ring (ticking noise)
Knocking or thumping
m
mUnintentional mechanical contact (eg fan
blades)
m mWorn drivebelt
m mPeripheral component fault (generator,
water pump, etc)
m mWorn big-end bearings (regular heavy
knocking, perhaps less under load)
m mWorn main bearings (rumbling and
knocking, perhaps worsening under load)
m mPiston slap (most noticeable when cold)
Engine noises
Low engine oil pressure
Engine overheatsEngine cuts out and will not restart
Fault FindingREF•11
REF
Crank engine and check for spark. Note
use of insulated tool

Glossary of Technical TermsREF•13
REF
A
ABS (Anti-lock brake system)A system,
usually electronically controlled, that senses
incipient wheel lockup during braking and
relieves hydraulic pressure at wheels that are
about to skid.
Air bag An inflatable bag hidden in the
steering wheel (driver’s side) or the dash or
glovebox (passenger side). In a head-on
collision, the bags inflate, preventing the
driver and front passenger from being thrown
forward into the steering wheel or windscreen.
Air cleanerA metal or plastic housing,
containing a filter element, which removes
dust and dirt from the air being drawn into the
engine.
Air filter elementThe actual filter in an air
cleaner system, usually manufactured from
pleated paper and requiring renewal at regular
intervals.
Allen keyA hexagonal wrench which fits into
a recessed hexagonal hole.
Alligator clipA long-nosed spring-loaded
metal clip with meshing teeth. Used to make
temporary electrical connections.
AlternatorA component in the electrical
system which converts mechanical energy
from a drivebelt into electrical energy to
charge the battery and to operate the starting
system, ignition system and electrical
accessories.
Ampere (amp)A unit of measurement for the
flow of electric current. One amp is the
amount of current produced by one volt
acting through a resistance of one ohm.
Anaerobic sealerA substance used to
prevent bolts and screws from loosening.
Anaerobic means that it does not require
oxygen for activation. The Loctite brand is
widely used.
AntifreezeA substance (usually ethylene
glycol) mixed with water, and added to a
vehicle’s cooling system, to prevent freezing
of the coolant in winter. Antifreeze also
contains chemicals to inhibit corrosion and
the formation of rust and other deposits that
would tend to clog the radiator and coolant
passages and reduce cooling efficiency.
Anti-seize compoundA coating that
reduces the risk of seizing on fasteners that
are subjected to high temperatures, such as
exhaust manifold bolts and nuts.
AsbestosA natural fibrous mineral with great
heat resistance, commonly used in the
composition of brake friction materials.Asbestos is a health hazard and the dust
created by brake systems should never be
inhaled or ingested.
AxleA shaft on which a wheel revolves, or
which revolves with a wheel. Also, a solid
beam that connects the two wheels at one
end of the vehicle. An axle which also
transmits power to the wheels is known as a
live axle.
AxleshaftA single rotating shaft, on either
side of the differential, which delivers power
from the final drive assembly to the drive
wheels. Also called a driveshaft or a halfshaft.
BBall bearingAn anti-friction bearing
consisting of a hardened inner and outer race
with hardened steel balls between two races.
BearingThe curved surface on a shaft or in a
bore, or the part assembled into either, that
permits relative motion between them with
minimum wear and friction.
Big-end bearingThe bearing in the end of
the connecting rod that’s attached to the
crankshaft.
Bleed nippleA valve on a brake wheel
cylinder, caliper or other hydraulic component
that is opened to purge the hydraulic system
of air. Also called a bleed screw.
Brake bleedingProcedure for removing air
from lines of a hydraulic brake system.
Brake discThe component of a disc brake
that rotates with the wheels.Brake drumThe component of a drum brake
that rotates with the wheels.
Brake liningsThe friction material which
contacts the brake disc or drum to retard the
vehicle’s speed. The linings are bonded or
riveted to the brake pads or shoes.
Brake padsThe replaceable friction pads
that pinch the brake disc when the brakes are
applied. Brake pads consist of a friction
material bonded or riveted to a rigid backing
plate.
Brake shoeThe crescent-shaped carrier to
which the brake linings are mounted and
which forces the lining against the rotating
drum during braking.
Braking systemsFor more information on
braking systems, consult the Haynes
Automotive Brake Manual.
Breaker barA long socket wrench handle
providing greater leverage.
BulkheadThe insulated partition between
the engine and the passenger compartment.
CCaliperThe non-rotating part of a disc-brake
assembly that straddles the disc and carries
the brake pads. The caliper also contains the
hydraulic components that cause the pads to
pinch the disc when the brakes are applied. A
caliper is also a measuring tool that can be set
to measure inside or outside dimensions of an
object.
CamshaftA rotating shaft on which a series
of cam lobes operate the valve mechanisms.
The camshaft may be driven by gears, by
sprockets and chain or by sprockets and a
belt.
CanisterA container in an evaporative
emission control system; contains activated
charcoal granules to trap vapours from the
fuel system.
CarburettorA device which mixes fuel with
air in the proper proportions to provide a
desired power output from a spark ignition
internal combustion engine.
CastellatedResembling the parapets along
the top of a castle wall. For example, a
castellated balljoint stud nut.
CastorIn wheel alignment, the backward or
forward tilt of the steering axis. Castor is
positive when the steering axis is inclined
rearward at the top.
Canister
Brake bleeding
Bearing
Air filter