1983 FIAT UNO engine

Vacuum servo unit and master
cylinder - general
54Access to the vacuum servo unit and the
master cylinder can only be obtained after the
cooling system expansion tank has been
released and moved aside (photo).
Antiskid system - description
55This system is available as an option on
the Turbo ie models only.
56The purpose of the system is to prevent
the wheel(s) locking during heavy brake
applications. This is achieved by automatic
release of the brake on a roadwheel which is
about to lock up, after which the brake is
re-applied. This cycle is carried out many
times per second under heavy braking,
retaining full steering control to avoid any
hazards.
57The main components of the system are
shown in Fig. 13.102. The control module
processes the signals received from the
sensors, and compares them with
deceleration values of the roadwheel and the
slip values of the tyre, which are stored in the
module memory.
58When reference values are exceeded and
wheel lock is imminent, the control module
signals the pressure modulators, which in turn
decrease the brake hydraulic pressure.
59Vehicle road speeds are also taken into
account by the module’s electronic circuits.
60In order to retain optimum system
performance, the tyres and wheels shouldalways be of the type originally fitted by the
vehicle manufacturer.
61Maintenance of the system should be
limited to checking the security of all electrical
and hydraulic connections. Individual compo-
nents are not repairable, and must be
renewed complete if faulty.15 Electrical system
Alternator (999 and
1108 cc models) -
removal and refitting
Á
1To remove the alternator from 999 cc
engine models, disconnect the leads from the
terminals on its rear face.
2Extract the screws and remove the plastic
drivebelt guard.
3Slacken the mounting and adjuster bolts,
push the alternator in towards the engine and
remove the drivebelt.
4Remove the mounting and adjuster bolts,
and withdraw the alternator downwards
through the gap between the right-hand
driveshaft and the engine sump pan (photo).
5Refitting is a reversal of removal; re-tension
the drivebelt.
Alternator (later models) -
removal and refitting Á
6Disconnect the battery negative lead.
7Loosen off the right-hand front roadwheelbolts, then raise and support the car at the
front end on axle stands. Remove the
right-hand roadwheel.
8Remove the wheel arch underwing shield
by driving the compression pins from the
centre of the retaining clips (using a 2 mm
drift), then prise free the panel retaining clips
and remove the shield. Keep the pins and
clips in a safe place and renew any that may
have been damaged during removal (photo).
9Detach the wiring connector from the
alternator.
10Release the alternator mounting and belt
adjuster link bolts, and take off the drivebelt.
11Take out the alternator top and bottom
mounting bolts.
Supplement: Revisions and information on later models 13•103
15.4 Removing the alternator from the
999 cc engine
Fig. 13.102 Braking system on Turbo ie Antiskid models (Sec 14)
13
1 Electronic control unit
(ECU)
2 Roadwheel speed
sensors
3 Pressure modulators
4 Vacuum reservoir
5 Check valve
6 Air cleaner
7 Load proportioning
(pressure regulating)
valves
8 Vacuum switch
9 ECU relay
10 System fault warning
lamp relay
11 System fault warning
lamp
12 Brake stop lamp
switch

15.23A Starter motor removal from the
1301 cc Turbo ie engine15.20 Starter motor removal from the
999 cc engine
12Disconnect the air cooling hose from the
rear cover of the alternator, and then unscrew
the fixing nuts and take off the rear cover with
hose spout. Mark the position of the cover on
the alternator before removing it, so that the
spout will be correctly positioned when
refitted (photos).
13Unbolt the driveshaft bearing
support/alternator bracket from the engine
crankcase, and swivel the support
downwards to provide space for withdrawal of
the alternator (photo).
14Withdraw the alternator from under the
right-hand front wing (photo).
15Refit in the reverse order of removal. Refit
the drivebelt and ensure correct engagement
with the pulleys, then set the drivebelt tension
and tighten the alternator retaining nuts.Alternator brushes -
renewal#
16Depending on model, the brush holder is
secured by two screws, which should be ex-
tracted and the brush holder removed (photos).
17New brushes and the holder are supplied
as an assembly.
Starter motor
(999 cc models) -
removal and refitting
Á
18To remove the starter motor from 999 and
1108 cc models, first disconnect the leads
from the starter motor terminals.
19Release the washer fluid reservoir flexible
bag from the engine compartment rear
bulkhead and move it to the left-hand side.
20Unscrew the starter motor mountingbolts, withdraw the starter from the flywheel
bellhousing, and then lift it out of the left-hand
side of the engine compartment (photo).
21Refitting is a reversal of removal.
Starter motor (1301 cc Turbo ie,
1372 cc ie,
1372 cc Turbo ie) -
removal and refitting
Á
22Disconnect the battery. Working from
under the front end of the car, unscrew the
starter motor mounting bolts and disconnect
the electrical leads.
23Withdraw the starter motor downwards. On
Turbo models, there is just enough clearance, if
the oil cooler hose and the oil pressure switch
lead are deflected carefully aside (photos).
24Refit by reversing the removal operations.
13•104 Supplement: Revisions and information on later models
15.16B Removing the alternator brush
holder
15.16A Extracting the alternator brush
holder screw15.14 Withdrawing the alternator15.13 Driveshaft bracket swivelled
downwards
15.12B Alternator rear cover and fixing nut15.12A Alternator air cooling hose15.8 Remove the wheel arch lower guard
panel for access to the alternator

Starter motor brushes
(later models) - renewal#
25When renewing the starter motor brushes
on later models, the old brushes will need to
be crushed (in a vice or with a hammer) and
their leads then soldered to the new brushes.
Fuses - later models
26The fuse arrangement is slightly different
on later models, but the circuits protected are
still identified by a symbol. Refer to the
Specifications Section for full details. Note
also the terminal block with plastic cover,
which can be used to isolate the battery from
the electrical system by disconnecting the
leads from the terminals (photos).
Relays (Turbo ie models) -
general
27On Turbo ie models, the relays mounted
in the fuse block are as shown in Fig. 13.103.
Additional relays are located as follows:
Headlamp relay - on lead under main fuse
blockFuel injection system main control relay -
adjacent to airflow meter
Headlamps later models
28The headlamp units fitted on later models
differ according to model, but the bulb and
unit replacement details are generally the
same as described for previous models in
Chapter 9. Note that the rubber cover can
only be fitted with the tab to the top as shown
(photo).
Headlamp beam adjusters for
load compensation - later
models
29Some later models are fitted with
headlamp beam adjusters which allowtemporary resetting to be made (such as
when the car is fully loaded). Access to these
adjusters is made by lifting the bonnet (photo).
30Turn the adjusters anti-clockwise to lower
the beam to the normal level or clockwise to
raise the beam (when the car is unloaded).
Repeat the procedure on the opposite
headlamp unit an equal amount.
31Other later models have separate
horizontal and vertical beam adjusters,
positioned as shown (photos). A load
compensating lever is attached to the
adjusters to enable temporary resetting of the
headlamp beams, without changing the
normal adjustment. Turn the lever to the
appropriate side (right or left) to make the
adjustment as required. The normal setting
Supplement: Revisions and information on later models 13•105
15.26B Battery lead terminal block on the
1301 cc Turbo ie model15.23B Starter motor and wiring
connections on the 1372 cc ie engine
15.31B Headlamp vertical beam alignment
adjuster screw on a 1372 cc ie model. Note
the load compensator lever which is set in
the “O” (normal load) setting position15.31A Headlamp horizontal beam
alignment adjuster screw on a 1372 cc ie
model
15.29 Headlamp beam adjuster on the
999 cc Turbo ie model15.28 Headlamp unit fitted to the 1372 cc ie
model
15.26A Fuse block on the 1301 cc Turbo ie
model
13
Fig. 13.103 Auxiliary fuses and relays on
1301 cc Turbo ie models (Sec 15)
1 Horn relay
2 Heated rear screen relay
3 Foglamps relay
4 Radiator fan relay
5 Electric windows relay
6 Foglamps fuse
7 Radiator fan second speed fuse
8 Fuel injector fan fuse
9 Electric windows fuse
10 Electric fuel pump fuse

adjustment procedures are the same as those
outlined for the previous model units in
Chapter 9, but ensure that the load
compensation lever is turned to the “O”
(normal load setting) position before making
any adjustments.
Headlamp unit removal - later
models
32The removal and refitting procedures
described in Chapter 9 also apply to the later
headlamp type, but note that later units are
secured in position by three retaining screws.
Headlamp dim-dip system -
description
33On later models, the wiring circuit has
been modified to prevent the car being drivenon parking lamps only in built-up areas.
34Headlamp intensity is reduced by the
transformer located at the front of the engine
compartment (photo).
35Any attempt to start the car with parking
lamps only on will automatically cause the
headlamps to switch on with a low-intensity
dipped beam. Dipped and main beam
function normally.
36The headlamp dim-dip system is a legal
requirement for all UK models registered after
April 1st, 1987.
Front fog lamps - bulb/unit
removal and refitting
and beam adjustment
ª
37Ensure that the front fog lamps are
switched off, then unscrew the two retainingscrews and withdraw the lamp unit from the
underside of the front bumper (photos).
38Undo the retaining screw and remove the
access cover from the unit (photo).
39Disconnect the wiring connector from the
bulb, release the clips and withdraw the bulb
from the lamp (photo).
40Refit in the reverse order of removal.
Check the light for satisfactory operation and
if the beam requires resetting, turn the
adjustment screw in the required direction.
41To adjust the beam, position the car 5 m
from, and square on to, a wall or similar.
42Measure the height of the centre of the
lamp lens from the ground and mark the
position on the wall. Switch on the lamp. The
demarcation line (cut-off) of the light should
be below the mark on the wall by 50 mm plus
one-third of the ground-to-lamp centre
measurement. Adjust the beam as required
using the long centre screw.
Horn - relocation
43The single horn, on applicable models, is
now located behind the grille, bolted on a
bracket attached to the top rail (photo).
Steering column combination
switches (later models) -
removal and refitting
Á
44Disconnect the battery negative lead.
45Undo the retaining screws and remove
the steering column shrouds (photos).
46Remove the steering wheel as described
in Chapter 10.
13•106 Supplement: Revisions and information on later models
15.45B . . . then remove the upper . . .15.45A Undo the retaining screws . . .15.43 Horn location
15.39 . . . detach the wires, extract the bulb15.38 . . . remove the rear cover . . .
15.37B . . . and withdraw the front fog lamp
unit . . .15.37A Undo the retaining bolts . . .15.34 Headlamp dim-dip transformer

47Loosen off the switch-to-column clamp
screw, disconnect the wiring connectors to
the switch and withdraw the switch from the
column (photos).
48Refit in the reverse order of removal, but
ensure that the lug of the switch aligns with
the slot in the column as it is fitted into
position. Check for satisfactory operation of
the switches on completion.
Instrument panel
(Turbo ie models) -
removal and refitting
Á
49The instrument panel on these models
incorporates an engine oil pressure gauge
and a turbo boost gauge. The latter is
connected directly to the inlet manifold.
50Apart from disconnecting the boost gauge
rubber hose, the instrument panel removal
and refitting procedure is as described in
Chapter 9 for the 1301 cc model or from
paragraph 57 in this Section for the 1372 cc
model.
51A digital electronic instrument panel is
available as an option on Turbo ie models.
The removal and refitting procedures differ
from analogue instrument panels in respect of
the electrical connections - a speedometer
drive cable is not used.
Facia-mounted switches
(1301 cc Turbo ie model) -
removal and refitting
Á
52Disconnect the battery.53Insert a thin-bladed screwdriver into the
joint between the switch block and the switch
block housing, to depress the plastic retaining
tabs. Do this carefully, otherwise the switch
block or casing will be damaged.
54Withdraw the switch block. Individual
switches can now be pushed out of the block.
Fibre optics are used to illuminate some
switches, these simply pull out of their
sockets (photos). The illumination bulb is
located on a crossmember found behind the
instrument pack. Removal of instruments/top
cover allows access.
55The switch housing can be removed after
extracting the fixing screws (photos).
56Refitting is a reversal of removal.
Instrument panel
(later models) -
removal and refitting
Á57Disconnect the battery negative lead.
58Unscrew and remove the two instrument
panel-to-facia retaining screws (photo).
59Remove the lower facia trim panel, which
is secured by two screws and a nut. Reach up
to the rear of the instrument panel to
disconnect the speedometer cable, then push
the panel from its recess in the facia.
Disconnect the multi-connectors from the rear
face of the panel and withdraw it (photo).
60Refit in the reverse order of removal.
Ensure that the speedometer cable is fully
engaged as the unit is refitted into position.
Supplement: Revisions and information on later models 13•107
15.47B . . . and remove the column switch15.47A Undo the retaining screw . . .15.45C . . . and the lower column
shroud . . .
15.58 Remove the retaining screws . . .15.55B Facia switch housing inner screw
removal on the 1031 cc Turbo ie model
15.54B Disconnecting a fibre optic cable
from its holder on the 1301 cc Turbo ie
model15.54A Switch block withdrawal on the
1301 cc Turbo ie model
15.55A Facia switch housing lower screw
removal on the 1301 cc Turbo ie model
13

Auxiliary control panel
(later models) -
removal and refitting
Á
61Disconnect the battery negative lead.
62Insert the flat of a screwdriver under the
trim piece at the end of the auxiliary panel as
shown and prise it free. Repeat the procedure
and remove the trim piece at the other end of
the panel (photo).
63Undo the retaining screws, withdraw the
panel from the facia. Disconnect the wiring
connectors from the panel switches to
remove the panel completely (photo).
64A switch bulb can be renewed by
untwisting the holder and removing the holder
and bulb.
65A switch unit can be removed from the
panel by unscrewing the four retaining screws.66Refitting is a reversal of the removal
procedure. Ensure that the wiring connections
are securely made and check for satisfactory
operation of the switches on completion.
Heater control panel
(later models) -
removal and refitting
Á
67Disconnect the battery negative lead.
68Pull free the heater/fresh air and blower
control knobs (photo).
69Undo the two retaining screws and
withdraw the control panel from the facia
(photos). Detach the wiring connectors from the
panel illumination lights and remove the panel.
70Refitting is a reversal of the removal
procedure. Ensure that the wiring connections
are securely made and on completion check
that the operation of the controls is satisfactory.
Trip master Á
71This electronic instrument is fitted into the
check panel of 1100SL and 1300SL models
from 1986.
72The device provides information on fuel
consumption, range, speed and elapsed time.
73With the ignition key turned to MAR,
figures are displayed in respect of the last
journey - average fuel consumption, average
speed and elapsed time (up to switching off
the ignition).
74As soon as the engine is started, the
instrument processes the current values to
include fuel consumption, range and the
actual time. 75Fuel consumption is only displayed when
the road speed exceeds 8.0 km/h (5.0 mph).
76The fuel range is only displayed after a
road speed of between 25.0 and 70.0 km/h
(15.0 to 44.0 mph) has been maintained for at
least 90 seconds or at higher speeds for
22 seconds.
77A reset button is provided, also a display
change button (from instant to average or
total values). Should the instrument reading
exceed 99 hours, 59 minutes or 1000 km
(622 miles) depressing the display change
button will display all zeros. Depress button E
to resume normal function.
78Refer to the end of the manual for a wiring
diagram of the check panel, incorporating the
trip master.
Interior roof mounted spotlamp,
switch and/or clock -
removal and refitting
Á
79Disconnect the battery negative lead.
80Prise free the lamp unit from its aperture
in the roof panel using a thin-bladed
screwdriver. The lamp bulb can be inspected
by untwisting the holder and withdrawing it
from the rear of the unit (photos). Extract the
bulb from the holder if it requires renewal.
81To remove the lamp switch from the
panel, reach through the lamp aperture and
press it free from the roof panel (photo).
Detach the wiring connectors.
82To remove the clock, reach through the
lamp aperture and undo the retaining screws
(photo). Withdraw the clock and detach the
wiring connectors.
13•108 Supplement: Revisions and information on later models
15.69B . . . and withdraw the heater control
panel15.69A . . . undo the retaining screws
(arrowed)15.68 Remove the control knobs . . .
15.63 . . . and withdraw the auxiliary
control panel
15.62 Prise free the trim covers for access
to retaining screws . . .15.59B . . . and disconnect the
speedometer cable15.59A . . . withdraw the instrument
panel . . .

As it is lifted, invert it and detach the washer
hose from the washer nozzle (photos).
97Where applicable, detach and remove the
washer reservoir from the recess in the front
of the windscreen to allow access to the wiper
motor.
98Unscrew and remove the two wiper motor
retaining screws. Lower and withdraw the
unit, then detach the cover from the motor.
Disconnect the wiring from the wiper motor
and withdraw it from the car (photos).
99Refit in the reverse order of removal.
Check for satisfactory operation of the wiper
and washer on completion.
Windscreen washer reservoir
(Turbo ie models) -
removal and refitting
Á
100Disconnect the battery negative lead.
101Remove the bonnet as described in
Chapter 12.
102Remove the wiper arm and blade as
described in Chapter 9, then unscrew and
remove the pivot nut.
103Undo the air inlet grille retaining screws
noting that two are not fitted with washers.
Where applicable, remove the washer
reservoir filler cap from the reservoir neck
protruding through the grille. Carefully prise
free and lift the air inlet grille clear of the body.
As it is lifted, invert it and detach the washer
hose from the washer nozzle.
104Syphon any remaining washer fluid from
the reservoir, then disconnect it and partiallywithdraw it from the recess in front of the
windscreen so that the wiring connection and
the washer supply hoses (to the windscreen
washer and the rear screen washer nozzles)
can be detached from the pump unit. Remove
the reservoir from the vehicle.
105Refit in the reverse order of removal. If the
washer pump unit was detached from the
reservoir, use a new seal washer when refitting
it. Top up the reservoir and check the screen
washers for satisfactory operation before
refitting the grille panel and the wiper arm/blade.
Tailgate wiper motor
(later models) -
removal and refitting
Á
106Although the tailgate wiper motor differs
in appearance, its removal and refitting
procedures are much the same as those
described for the earlier models in Section 27
of Chapter 9 (photo).
Radio
107All later models are now equipped with
power supply and speaker leads for radio
installation.
108Installation of the standard FIAT aerial
mounted on the windscreen pillar is shown
(photos).
Check control system sensors -
description
109The locations of the sensors referred to in
Chapter 9, Section 34 are given in the
following paragraphs, and their construction
differs according to their individual function.
Brake fluid level sensor
110This is mounted in the master cylinder
fluid reservoir cap, and comprises a pair of
reed switches in a glass bulb, and a magnet at
the end of a float.
111When the fluid level is correct, the
magnetic flux closes the switches. In the
event of a leak in the system, the magnet
moves away, the switches open and the
warning lamp comes on.
Brake disc pad wear sensor
112This is basically a circuit wire embedded
in the pad friction material. As the pad wears,
the wire is eventually exposed and contacts
the disc, whereupon the warning lamp comes
on to indicate that pad renewal is necessary.
Coolant level sensor
113This is located in the cooling system
expansion tank, and is of the reed switch
type, which operates in a similar way to that
described for the brake fluid sensor.
Engine oil level sensor
114This is located at the end of the dipstick,
and comprises a pair of switches at the end of a
bi-metallic strip, heated by electrical resistance.
115The heat is dissipated by the immersion
of the dipstick in the engine oil, so preventing
the bi-metallic strip from curving so much that
the switches would open.
116If the oil level drops, the heat is no longer
dissipated, the switches open, and the
warning lamp comes on.
13•110 Supplement: Revisions and information on later models
15.108B Pillar lower screw for aerial15.108A Pillar upper screws for aerial15.106 Tailgate wiper motor - later model
15.98C . . . and detach the wiring
connector15.98B . . . separate the wiper motor from
its cover . . .15.98A Remove the wiper motor retaining
screws . . .

Door closure sensor
117The sensor consists of a microswitch
within the lock. The switch actuates the
warning lamp according to whether the lock is
in the open or closed mode.
Check control system sensors -
testing
Brake fluid level sensor
118With the fluid level correct, switch on the
ignition and depress the centre of the
reservoir cap. If the sensor switches are
working correctly, then “FAULT” should be
indicated on the check panel.
Coolant level sensor
119With the coolant level in the expansion
tank correct, switch on the ignition and then
pull the wiring plug from the sensor. “FAULT”
should be indicated on the check panel. If it is
not, then it is the panel which is faulty.
120An ohmmeter should be used to check
for continuity, holding the float in both the full
and low level positions.
Engine oil level sensor
121With the oil level correct, disconnect the
wiring plug from the dipstick, and then bridge
the plug terminals (not dipstick side) with a 12
ohm resistor. Switch on the ignition.
122If the red light on the check panel goes
out, then the fault is due to the sensor.
123If the light stays on, then it is the check
panel module which is faulty.
Door closure sensor
124Any fault in the lock microswitch can best
be detected using an ohmmeter.
16 Suspension
Front anti-roll bar -
removal and refittingª
1A front anti-roll bar is fitted to the 1301 cc,
1372 cc ie and 1372 cc Turbo ie engined
models. Removal of the bar on all models isas follows. Firstly loosen off the front
roadwheel bolts, then raise the front of the
car, securely support it on axle stands and
remove the front roadwheels.
2Disconnect the two gearchange rods from
the transmission.
3Unbolt and disconnect the anti-roll bar
insulating clamps from the floorpan (photo).
4Unbolt the end links from the track control
arms and withdraw the anti-roll bar (photo).
5Refitting is a reversal of removal, but only
tighten the nuts and bolts to the specified
torque with the car parked on level ground,
with four passengers and 40 kg of luggage
inside.
Suspension strut - later models
6The suspension strut upper mounting nuts
on later models also secure the brackets for
the mounting of ancillary components such as
the fuel filter, fuel system relays and fuses,
etc. (depending on model).
7When removing the suspension strut units,
it will therefore be necessary to detach and
support these brackets and their fittings
(photo).
17 Bodywork
Plastic components
1With the use of more and more plastic
body components by the vehicle
manufacturers (e.g. bumpers, spoilers, and in
some cases major body panels), rectification
of more serious damage to such items has
become a matter of either entrusting repair
work to a specialist in this field, or renewing
complete components. Repair of such
damage by the DIY owner is not really
feasible owing to the cost of the equipment
and materials required for effecting such
repairs. The basic technique involves making
a groove along the line of the crack in the
plastic using a rotary burr in a power drill. The
damaged part is then welded back togetherby using a hot air gun to heat up and fuse a
plastic filler rod into the groove. Any excess
plastic is then removed and the area rubbed
down to a smooth finish. It is important that a
filler rod of the correct plastic is used, as
body components can be made of a variety
of different types (e.g. polycarbonate, ABS,
polypropylene). Damage of a less serious
nature (abrasions, minor cracks, etc.) can be
repaired by the DIY owner using a two-part
epoxy filler repair material. Once mixed in
equal proportions, this is used in similar
fashion to the bodywork filler used on metal
panels. The filler is usually cured in twenty to
thirty minutes, ready for sanding and
painting.
2If the owner is renewing a complete
component himself, or if he has repaired it
with epoxy filler, he will be left with the
problem of finding a suitable paint for
finishing which is compatible with the type of
plastic used. At one time the use of a
universal paint was not possible owing to the
complex range of plastics encountered in
body component applications. Standard
paints, generally speaking, will not bond to
plastic or rubber satisfactorily. However, it is
now possible to obtain a plastic body parts
finishing kit which consists of a pre-primer
treatment, a primer and coloured top coat.
Full instructions are normally supplied with a
kit, but basically the method of use is to first
apply the pre-primer to the component
concerned and allow it to dry for up to
30 minutes. Then the primer is applied and
left to dry for about an hour before finally
applying the special coloured top coat. The
result is a correctly coloured component
where the paint will flex with the plastic or
rubber, a property that standard paint does
not normally possess.
Rear view mirrors Á
Interior
3The mirror is of safety type, “breaking” off
its ball fixing upon impact from a front seat
occupant.
4To remove the mirror, grip the head and
Supplement: Revisions and information on later models 13•111
16.7 Suspension strut upper mounting
nuts, showing bracket and cable clip on
the 1372 cc ie model16.4 Anti-roll bar fixing nuts (arrowed)16.3 Anti-roll bar clamp
13