1995 RENAULT MEGANE SCENIC heater

DIESEL EQUIPMENT
Pre-post-heating unit
13
LOCATION
Pre-post-heating unit (A)
This unit has two diodes to prevent the feeding of
the heater plugs when the air conditioning system
is operating and also has a CTN type air
temperature sensor.Coolant temperature sensor (1) (black connector)
99335R
BAir conditioning diaphragm control solenoid
valve on injection pump (fast idle)
CEGR control solenoid valve
98904R
SPECIFICATIONS
Temperature in °C ± 1Resistance Ω
252 610 to 2 990
80310 to 350
13-31

DIESEL EQUIPMENT
Pre-post-heating unit
13
PRINCIPLE OF OPERATION FOR GAS PRE-POST-
HEATING
1. "Pre-heating" when the ignition is turned on
a) Variable pre-heating
The time period during which the warning
light is illuminated and the heater plugs
are fed is dependent on the coolant
temperature.3. "Post-heating" while the engine is running
Post-heating has two phases:
a) Fixed post-heating
After the engine has been started, the
plugs are for for 10 seconds.
b) Variable post-heating
Variable post-heating begins when fixed
post-heating has ended.
During this phase, the plugs are fed
alternately 1 - 3 and 2 - 4 depending on
the coolant temperature.
If the coolant temperature sensor is faulty,
the heater plugs are fed systematically for
14 seconds.
b) Fixed pre-heating
After the pre-heating warning light has
extinguished (variable pre-heating), the
plugs remain fed for up to 8 seconds
before the engine is started.
2. Starting
The plugs remain fed while the starter is
activated.If the coolant temperature sensor is faulty,
the heater plugs are fed systematically for
30 seconds.
Variable post-heating may be
interrupted:
- finally when the coolant temperature
> 65°C,
- momentarily when the unit receives
full load information (post-heating
microswitch opens) for more than 1
second ; post-heating begins again
when the engine returns to idle speed
or low load (microswitch closes).
DI1304
DI1305
13-32

DI1306
DIESEL EQUIPMENT
Injector holder - heater plug
13
94952R1
1 + 2Injector holder assembly.
3Seal between the injector holder assembly
and the cylinder head.
4Flame arresting washer.
5Injector protector.
The injector holder assembly is screwed into the
cylinder head.
In order to remove the injector high pressure
pipes, use wrench B.Vi. 868 . To remove the
injector holder assembly, use the 27 mm long
socketMot. 997.
The following tightening torques must be
observed:
- lower section (2) on upper section (1) of the
injector holder : 7 ± 1 daN.m,
- injector holder on cylinder head: 7 ± 1 daN.m.
Each time an injector holder is removed, the
copper seal and the flame arresting washer must
be renewed.
SPECIFICATIONS
Injector holder (A)
Position of the flame arresting washer
Injector nose
To pre-combustion chamber
Heater plug (B)
Current: 15A after 8 seconds heating
Tightening torque : 2 daN.m
13-36

DIESEL EQUIPMENT
Fuel filter
13
LOCATION
Principle of the electric heater
The heater has heated studs. They are ceramic,
made from barium titanate which has a positive
temperature coefficient, meaning that its
resistance increases as its temperature increases.
99332R
1Fuel filter
2Electric heater
3Hand priming unit
The electric diesel fuel heater and the thermostat
are integral in the head of the filter.
DIAGRAM
PRJ99258
449Electric heater
450Diesel heating relay
597Engine fuse box
645Passenger compartment fuse box Operating temperature
Electrical circuit closes: 0°C
Electrical circuit opens: from 8°C
Heater power: 150 W
13-37

INJECTION
Operating wiring diagram
17
KEY TO OPERATIONAL WIRING DIAGRAMS (E7J, F3R, K7M)
COMPONENT NO DESCRIPTION
109
119
120
146
147
149
193 to 196
218
222
224
225
228
236
238
242
244
247
250
272
310
319
341
371
398
437
565
597
645
649
663
664
679
746
772
777
927
MF
MHOn board computer
Automatic transmission computer
Injection computer
Pinking sensor (located under the inlet manifold for E7J engine)
Absolute pressure sensor
TDC sensor
Injectors
Fuel pump
Throttle position potentiometer
Power assisted steering pressostat
Diagnostic socket
Idle speed regulation micromotor
Fuel pump relay (in engine fuse box)
Injection feed locking relay
Oxygen sensor
Coolant temperature sensor
Instrument panel
Vehicle speed sensor
Air temperature sensor
Ignition power module
Air conditioning control panel
Idle speed regulation solenoid valve
Fuel vapour recirculation solenoid valve
Exhaust gas recirculation solenoid valve (EGR)
Throttle body heater (under throttle body)
Throttle body assembly
Engine fuse box
Passenger compartment connection unit
Idle speed regulation stepping motor
Dual ignition coil n°1 (cylinders 1 and 4)
Dual ignition coil n° 2 (cylinders 2 and 3)
Radio anti-interference condenser
Cylinder reference sensor
Heater relay (in engine fuse box)
Power fuse board (near battery)
Inertia switch
Rear right hand electrical earth
Engine electrical earth (located on the cylinder block between the starter and the al-
ternator for the E7J engine)
17-39

INJECTION
Operating wiring diagram
17
E7J engine
COMPUTER TRACK ALLOCATION
TrackALLOCATION
1Power earth
2Electronic earth
3Vehicle speed information
4+ before ignition (permanent) computer memory
5Canister bleed signal (sequential earth period)
6Pump relay control (via track N° 2)
7Locking relay control (via track N° 2)
8Diagnostic line for erasing the memory and power assisted steering pressostat information
9Throttle position potentiometer information (pin N° 4 on 222)
10Heater relay command
11TDC sensor signal (track B)
12Rev counter information at instrument panel
13Connection with injection fault warning light on instrument panel
14Air temperature information
15Coolant temperature information
16+ 5 V feed for absolute pressure sensor and throttle potentiometer
17Common earth for absolute pressure sensor, throttle potentiometer and coolant temperature
sensor
18Emission of diagnostic signal to diagnostic socket
19Main computer feed via injection locking relay
20Air conditioning compressor command
21Injector control via earth
22Not used
23+ or - feed to idle speed micromotor (pin N° 1)
24+ or - feed to idle speed micromotor (pin N° 2)
17-41

COOLING
Filling - bleeding
19
There is no water control valve.
Coolant circulates continuously in the heater
matrix, assisting with engine cooling.
FILLING
The following bleed screws must be opened:
- on the top of the radiator,
- on the heating hose,
- on the thermostat mounting(except E7J- K7M
engines ).
Fill the circuit at the expansion bottle opening.
Close the bleed screws as soon as fluid runs out in
a continuous jet.
Start the engine (2 500 rpm).
Adjust the level by overflow for approximately
4 minutes.
Close the expansion bottle.
BLEEDING
Let the engine run for 20 minutes at
2 500 rpm,until the engine cooling fan operates
(time required for automatic degassing).
Check the fluid level is close to the "Maximum"
mark.
NEVER OPEN THE BLEED SCREWS WHEN THE
ENGINE IS RUNNING.
TIGHTEN THE EXPANSION BOTTLE CAP WHEN THE
ENGINE IS WARM.
19-2

COOLING
Diagram
19
1 Engine
2 Radiator
3 Expansion bottle with degassing after ther-
mostat
4 Heater matrix
5 Thermostat mounting
6 Oil temperature exchanger
7 3 mm diameter restriction
8 6 mm diameter restrictionWater pump
Thermostat
Bleed valve
Temperature switch
The rating of the expansion bottle cap is 1.2 bar
(brown).
99417R
F8Q ENGINE
19-6