1983 FIAT UNO heater

the trim cover, undo the retaining screw at the
rear of the console. Prise free and release the
gear lever gaiter and lift clear the central
console.
7Undo the retaining screws and remove the
steering column upper and lower shroud.
8Detach and remove the lower facia trim on
the side of the central facia.
9Referring to Fig. 13.32, unscrew and
remove the four heater facia to main facia
retaining screws from the points indicated.
10Undo the two retaining nuts securing the
heater to the body on the driver’s side.
11Undo the retaining screws and remove
the pipe shield from the side of the heater
unit, then disconnect the coolant supply and
return hoses from the heater. As the hoses are
detached, be prepared to catch any remainingcoolant as it flows from the hoses and heater
connections.
12Undo the remaining two heater unit
securing nuts and withdraw the heater unit
from the car. As the unit is removed, detach
the wiring and position the hoses with their
ends pointing upwards to avoid further
coolant spillage.
13Refit in the reverse order of removal.
Ensure that the hoses are securely
reconnected. Top up the cooling system on
completion.
Heater unit - dismantling
and reassemblyÁ
14Remove the heater unit as described
previously.
15Pull free the heater/fresh air and blower
control knobs (photo).
16Undo the two retaining screws and
withdraw the control panel from the facia.
Detach the wiring connectors from the panel
illumination lights and remove the panel.17Unscrew the retaining bolts and remove
the centre panel from the heater unit.
18Undo the retaining screws and remove
the control lever mounting.
19Loosen off the grub screws and detach
the cables from the control levers.
20Undo the retaining screws and remove
the control valve.
21Undo the two retaining screws and
withdraw the heater matrix from the heater
housing.
22To separate the casing halves, drill out the
pop rivet securing the mounting bracket,
release the retaining clips and unscrew the
securing bolts.
23Reassemble in the reverse order of
dismantling. Check that the control cables are
correctly adjusted and that the controls
operate in a satisfactory manner before
refitting the heater unit to the car.
Supplement: Revisions and information on later models 13•59
8D.15 Pull free the heater/fresh air and
blower control knobs
Fig. 13.33 Heater pipe shield securing
screw positions on later models (Sec 8D)
Fig. 13.32 Heater unit facia to main facia
retaining screw locations (arrowed)
(Sec 8D)
Fig. 13.34 Heater unit components on later models (Sec 8D)
1 Coolant inlet tap 2 Centre panel 3 Side casings 4 Heater matrix 5 Blower fan
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 . . .

Wiring diagrams 14•1
14
Component key for wiring diagrams 1 to 29
Note: Not all the items listed will be fitted to all models
No Description
00200 Alternator with built-in regulator
00500 Battery
01001 Starter motor
01202 Rear front electric window motor
01203 Left front electric window motor
01206 Windscreen wiper motor
01207 Rear screen wiper motor
01252 Right front door locking motor
01253 Left front door locking motor
01254 Right rear door locking motor
01255 Left rear door locking motor
01400 Windscreen washer pump
01401 Rear screen washer pump
01420 Electric fuel pump
01500 Engine cooling fan
01502 Injector cooling fan
01504 Ventilation fan
02001 Engine cut-out solenoid on injection pump
02010 Fuel injector
02011 Fuel injector
02012 Fuel injector
02013 Fuel injector
02015 Supplementary air valve
02210 Accelerator pump outlet cut-out solenoid on
carburettor
02215 Supplementary air valve
02400 Ignition coil
02405 Ignition coil with electronic control unit
02490 Static advance ignition control unit
02492 Microplex ignition system control unit
03000 Insufficient engine oil pressure switch
03002 Right front door ajar switch
03003 Left front door ajar switch
03004 Right rear door ajar switch
03005 Left rear door ajar switch
03006 Handbrake ‘on’ warning switch
03007 Brake stop-lamp switch
03008 Reversing light switch
03028 Radiator thermostatic switch
03029 Coolant overheating warning light thermostatic switch
03034 Injector cooling fan thermostatic switch
03035 Accelerator pump outlet cut-out solenoid thermostatic
switch
03036 Radiator thermostatic switch with two operating ranges
03053 Map reading light switch
03059 Foglamps switch
03060 Rear foglamp switch
03110 Heated rear screen switch
03114 Ventilation fan switch
03123 Air pressure switch
03142 Choke warning light switch
03144 Reset switch
03145 Display switch
03305 Right front door open light push button
03306 Left front door open light push button No Description
03319 Horn push button
03500 Ignition switch
03505 Butterfly valve cut-off switch
03506 Throttle position switch
03530 Right front electric window switch
03531 Left front electric window switch
03546 Rear screen wash/wipe switch
03550 Hazard warning lights switch
04010 Steering column switch unit, direction indicators
04022 Steering column switch unit, headlamps, main beam
and dipped, side lights
04032 Steering column switch unit, windscreen wash/wipe
04214 Fuel injection system control relay
04215 Antiskid system failure relay
04225 Radiator fan 2nd speed engagement relay feed
04241 Foglamps relay feed
04260 Electric windows motor relay feed
04283 Antiskid system relay
04291 Horn relay feed
04292 Heated rear screen relay feed
04441 Dim-dip cut-out 04600 Ignition distributor
04700 Coolant temperature sender unit
04701 Electronic injection coolant temperature sender unit
04720 Oil pressure sender unit
05008 Right headlamp, main beam and dipped with side light
05009 Left headlamp, main beam and dipped with side light
05013 Abnormal fuel consumption sensor
05015 Right foglamp
05016 Left foglamp
05410 Right front direction indicator
05411 Left front direction indicator
05412 Right front side direction indicator
05413 Left front side direction indicator
05640 Rear number plate lamp
05690 Right rear light cluster, sidelight, direction indicator,
brake light, rear foglamp
05691 Left rear light cluster; side light, direction indicator,
brake light, rear foglamp
06000 Centre courtesy light
06026 Map reading light
06076 Ideogram fibre optic light
06080 Heater controls light
06084 Instrument panel light
06300 Sidelights warning light
06305 Main beam headlamps warning light
06310 Rear foglamps warning light
06311 Foglamps warning light
06315 Hazard warning lights warning light
06320 Direction indicators warning light
06335 Insufficient brake fluid level warning light
06336 Handbrake ‘on’ warning light
06343 Insufficient engine oil pressure warning light
06344 Insufficient brake fluid level warning light
06345 Fuel reserve warning light
06350 Coolant overheating warning light

14•8 Wiring diagrams
Wiring diagram 11 - courtesy lamps, heater fan, heater illumination, cigar
lighter, digital clock and radio (S and SX models)
Wiring diagram 12 - courtesy lamps, heater fan and heater illumination
(Comfort and ES models)

Wiring diagrams 14•15
14
Wiring diagram 22 - direction indicators, hazard warning lamps, brake stop-
lamps, horn and low brake fluid sensor (1301 cc Turbo ie model)
Wiring diagram 23 - courtesy lamps, heater fan, heater illumination, cigar
lighter, digital clock, radio, low oil pressure lamp, oil pressure switch, oil
temperature gauge and tachometer (1301 cc Turbo ie model)

14•20 Wiring diagrams
Component key for wiring diagrams 30 to 52
Note: Not all the items listed will be fitted to all models
No Description
1 Injector cooling fan
2 Left front light cluster
3 Left foglamp
4 Left front engine compartment earth
5 Radiator cooling fan
6 Double contact thermostatic switch
on engine radiator
6A Thermostatic switch on engine
radiator
7 Left horn
8 Right horn
9 Resistor for engaging radiator fan 1st
speed
10 Right front light cluster
11 Right foglamp
12 Right front engine compartment earth
13 Battery
14 Ignition coil
15 Ignition distributor with magnetic
impulse generator
16 Left front side direction indicator
17 Ignition power module
18 MPi electronic injection control unit
19 Join between injection/ignition cables
in engine compartment
20 Battery cables join in engine
compartment
21 Antiskid braking system wiring join
22 Starting go-ahead relay
23 Earth for battery
24 Radiator coolant temperature sender
unit for electronic injection
25 Anti-knock sensor
26 Injection system diagnostic socket
27 Switch signalling insufficient engine
oil pressure
28 Radiator coolant temperature sender
unit
29 Engine oil temperature sender unit
30 Engine oil pressure sender unit
31 Right front side direction indicator
32 Engine oil temperature sender unit
cable join
33 Battery recharging signal cable join
34 Windscreen washer pump
35 Rear screen washer pump
36 Reversing switch
37 Fuel injectors relay feed
38 Insufficient brake fluid level sensor
39 Left brake pad wear sensor
40 Microplex electronic ignition control
unit
41 Injection cables join in engine
compartment
42 Ignition cables join in engine
compartment
43 Join between battery cable and
injection cables
44 Join between engine cable and
battery cables
45 Left front brake pad cables join
46 Starter motorNo Description
47 Windscreen wiper motor
48 Headlamp washer pump
49 Fuel injector
50 Fuel injector
51 Fuel injector
52 Fuel injector
53 Supplementary air valve
54 Spark plug
55 Spark plug
56 Spark plug
57 Spark plug
58 Excess supercharging pressure
switch
59 Throttle position switch
60 Engine speed sensor
61 Ignition diagnostic socket
62 Connector block
63 Connector block
64 Alternator
65 Thermostatic switch for injector
cooling fan
66 Right brake pad wear sensor
67 TDC sensor
68 Connector block
69 Connector block
70 Connector block
71 Connector block
72 Join with right brake pad cables
73 Electronic earth
74 Power earth
75 Brake stop-lamp switch
76 20 A fuse for central locking
77 10 A fuse for electric fuel pump
78 30 A fuse for radiator cooling fan
79 30 A fuse for electric windows
80 10 A fuse for injector cooling fan
81 20 A fuse for headlamp
wash/wipe
82 20 A fuse for foglamps
83 Junction box with fuses and relays:
E1 Horn relay (for single tone horns
bridge between 86 and 87)
E2 Heated rear screen relay
E3 Heater (bridge between 85 and 30)
84 Join between front cable and rear
cables
85 Join between front cable and door
ajar sensor cables
86 Earth on dashboard, left hand side
87 Earth on dashboard, right hand
side
88 Choke warning light switch
89 Ignition switch
90 Hazard warning lights switch
91 Steering column switch unit
A Rear screen wash/wipe switch
B Horn button
C Direction indicators switch
D Windscreen wiper intermittent
speed selector switch
E Windscreen/headlamp washer
control switchNo Description
F Rear foglamps/headlamp washer
intermittent device switch
G Headlamp dip switch
H External lights switch
I Flasher switch
92 Foglamp relay
93 Electric fuel pump relay
94 Electric windows relay feed
95 Headlamp wash/wipe intermittent
device
96 Direction indicators/hazard warning
lights flasher unit
97 Central locking receiver
98 Central locking control unit
99 Join with brake pad cables
100 Join between engine cable and
dashboard cables
101 Automatic heater cable join
102 Instrument panel
A Foglamps warning light
B Main beam headlamps warning
light
C Side lights warning light
D Rear foglamps warning light
E Heated rear screen warning light
F Hazard warning lights warning
light
G Direction indicators warning light
H Handbrake applied and insufficient
brake fluid level warning light
I Choke warning light
K Instrument panel light bulbs
L Battery recharging warning light
M Insufficient engine oil pressure
warning light
O Antiskid braking system failure
warning light
P Maximum turbocharging pressure
warning light
Q Brake pad wear warning light
R Door ajar warning light
U Fuel level gauge
V Engine oil pressure gauge
W Engine oil temperature gauge
Y Tachometer
Z Coolant temperature gauge
103 Join with remote control central
locking cables
104 Cigar lighter
105 Radio receiver
106 Heater unit
107 Switch unit
A Heated rear screen switch
B Rear foglamps switch
C Switch unit light bulb
D Rear screen wiper switch
E Foglamps switch
F Clock
108 Left front electric window motor
109 Left front central locking geared
motor
110 Switch signalling left front door ajar

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)

Wiring diagrams 14•37
14
Wiring diagram 45 - radiator cooling fan, heater, radio and cigar lighter (1990-on 45, 55, 70 and 1.4 models)