sensor RENAULT MEGANE SCENIC 1995 Service Manual PDF

INJECTION
Special notes on sequential injection
17
F3R engine
1.REMOVING THE CYLINDER REFERENCE
SENSOR
Disconnect the sensor
Remove:
- the cylinder reference sensor (A) (one bolt),
- the cover (B) (three bolts).
Target (C) is secured on the end of the camshaft
by a spring ring.
To release the target from the camshaft:
• Rest a copper hammer behind the target.
• Use a mallet to tap the hammer gently.
• Remove the target (C) and the plastic
protective cover (D).
IMPORTANT : the order of operations described
below MUST be observed. Not following the
method could cause incorrect operation and / or
damage to the sensor.
2.REFITTING THE CYLINDER REFERENCE SENSOR
Refit :
- the sensor to the cover, push it upwards and
tighten to a torque of 0.15 daN.m,
- the protective plastic cover,
- the target (this has a foolproofing device.
Check its position before fitting to the end of
the camshaft),
- the cover with the sensor. Tighten the three
cover bolts to a torque of 1 daN.m.3.
ADJUSTING THE SENSOR / TARGET GAP
Slacken the bolt mounting the sensor without
touching the sensor then retighten it to a torque
of 0.8 daN.m.
By slackening the bolt the sensor is released. A
spring in the cover pushes the sensor against the
target.
When the bolt is tightened the sensor is secured. It
has two small plastic pips which touch the target.
These pips wear as the engine turns. There is no
longer contact between the two components and
the gap is set.
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INJECTION
Special notes on sequential injection
17
F3R engine
CYLINDER REFERENCE SENSOR CONNECTIONS
TRACK ALLOCATION
1 Earth
2 Information to injection computer on track 42
3 +after ignition
1REMOVAL2REFITTING
DI1701DI1702
DI1703
3ADJUSTMENT
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INJECTION
Injection fault warning light
17
PRINCIPLE FOR ILLUMINATION OF THE INJECTION FAULT WARNING LIGHT ON THE INSTRUMENT PANEL
• Vehicle without engine immobiliser system
When the ignition is turned on, the warning light illuminates for 3 seconds then extinguishes.
• Vehicle with engine immobiliser system deactivated
When the ignition is turned on, the warning light illuminates for 3 seconds then extinguishes.
When the doors are unlocked, the red immobiliser warning light, which was previously flashing, extin-
guishes. When the ignition is turned on, it illuminates for 3 seconds then extinguishes.
• Vehicle with engine immobiliser system activated
When the ignition is turned on, the computer does not identify the code and the vehicle cannot be star-
ted. The injection warning light illuminates for 3 seconds then extinguishes.
Before the ignition is turned on, the red immobiliser warning light flashes. When the ignition is turned
on, this light flashes twice as fast.
If a fault in the immobiliser system is detected when the engine is running, the injection warning light
will flash in the engine speed range from idle speed to 1 500 rpm approximately.
• Fault with an injection system component
Faults in the following components cause the warning light to illuminate:
- absolute pressure sensor,
- throttle position potentiometer,
- injectors,
- idle speed regulation stepping motor (K7M engine),
- idle speed regulation valve (F3R engine),
- no vehicle speed information when the vehicle is moving,
- EGR solenoid valve (K7M 703 engine),
- automatic transmission computer → injection computer (F3R - K7M engines).
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OXYGEN SENSOR VOLTAGE (#05)
Reading #05 on the XR25 : the value read is the voltage sent to the computer by the oxygen sensor; it is ex-
pressed in Volts (the value actually varies between 0 and 1 000 millivolts).
When the engine is in the loop phase, the voltage value should oscillate rapidly and should be between
50±50 mV (lean mixture) and 850 ± 50 mV (rich mixture) and vice versa.
The smaller the gap between the upper and lower oscillating values, the poorer the information from the
sensor (the gap is usually at least 500 mV).
RICHNESS CORRECTION (#35)
The value given under # 35 on the XR25 represents the average value of richness corrections made by the
computer depending on the richness of the burnt mixture as seen by the oxygen sensor (the oxygen sensor ac-
tually analyses the oxygen content of the exhaust gases directly from the richness of the burnt mixture).
The richness correction has a centre point of 128 with thresholds of 0 and 255 (experience has shown that un-
der normal operating conditions # 35 is located close to 128 with only a small amount of variation).
- Value less than 128 : request for mixture to be made leaner
- Value greater than 128 : request for mixture to be made richer
ENTRY INTO RICHNESS REGULATION MODE
Loop phase
Richness regulation begins after the timed starting period :
- for no load if the coolant temperature has reached:
•25°C for E7J engines,
•40°C for K7M engines,
•35°C for F3R engines.
- outside no load conditions if the coolant temperature is greater than :
•+ 20°C for K7M engines,
•+ 15°C for F3R engines,
there is no coolant temperature condition for E7J engines.
The timed starting period is dependent on the coolant temperature:
-at20°C it is a maximum of :
•45 seconds for E7J engines,
•1 minute for K7M engines,
•2 minutes for F3R engines,
-at80°C it is a maximum of :
•9 seconds for E7J engines,
•16 seconds for K7M engines,
•1 minute for F3R engines.
if richness regulation has not yet started,#35 = 128
INJECTION
Richness regulation
17
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INJECTION
Richness regulation
17
Non-loop mode
When richness regulation is occurring, the operating phases when the computer ignores the voltage in-
formation from the oxygen sensor are:
- Full load: #35 = variable and greater than 128
- Sharp acceleration: #35 = variable and greater than 128
- Sharp deceleration with no load information (injection cut) : #35 = 128
- Oxygen sensor fault: #35 = 128
DEFECT MODE IN THE EVENT OF AN OXYGEN SENSOR FAULT
If the voltage from the oxygen sensor is incorrect (# 05 varies only slightly or not at all) during richness regu-
lation, the computer will only enter defect mode (# 35 = 128) if the fault has been present for 3 to 5 minutes.
The fault will be memorised in this case only.
If an oxygen sensor fault is present and recognised and if the fault has already been stored, the system enters
the open loop mode directly (# 35 = 128).
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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)
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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)
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INJECTION
Operating wiring diagram
17
E7J engine
TrackALLOCATION
25No load information input
26Not used
27Power module command
28TDC sensor signal input (track A)
29Immobiliser coded line input via decoder unit
30+ 12 V information when ignition turned on
31Pinking sensor noise signal input
32+ 12 V after ignition information
33Voltage information dependent on manifold pressure seen by sensor (on track B)
34Air conditioning compressor operation request input
35Voltage from oxygen sensor input
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INJECTION
Operating wiring diagram
17
K7M engine
COMPUTER TRACK ALLOCATION
TrackALLOCATION
1Not used
2Power earth n° 1
3Power earth n° 2
4Command for injector n° 2 and n° 3 via earth
5Air conditioning on - off information and request for compressor operation authorisation
(0 - 12 V)
6Heated windscreen information (0 - 12 V)
7Park / Neutral / torque reduction information (0 - 5 V) (K7M 703)
8Pinking sensor signal
9Stepping motor control (0 - 12 V)
10EGR solenoid valve control (0 - 12 V) (K7M 703)
11Bi-directional diagnostic line K used for entry into fault finding mode
(looking for computer), emission of diagnostic signals from computer, application of command
modes (G..*), erasing the memory (G0**)
and ending fault finding (G13*)
12Vehicle speed information
13Power assisted steering pressostat information
14Not used
15Coolant temperature sensor information
16Manifold pressure information transcribed by absolute pressure sensor
17Voltage information from oxygen sensor
18Earth
19Throttle position potentiometer information
20Air temperature sensor information
21Not used
22Not used
23Not used
24+ 12 V after ignition
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INJECTION
Operating wiring diagram
17
TrackALLOCATION
25Not used
26Not used
27Not used
28Command for coil for cylinders 1 and 4
29Command for coil for cylinders 2 and 3
30Command for injector n° 1 and n° 4 via earth (n° 1 flywheel end)
31Pinking sensor screened cable
32+12 V before ignition
33TDC sensor signal (track B)
34TDC sensor signal (track A)
35Stepping motor command (0 - 12 V)
36Stepping motor command (0 - 12 V)
37Immobiliser coded line input
38Uni-directional diagnostic line L for entry into diagnostic mode only
(looking for computer)
39Not used
40Stepping motor command (0 - 12 V)
41Throttle angle information for automatic transmission computer
42RCO control (sequential earth period for canister bleed solenoid valve RCO)
43Command for injection fault warning light on instrument panel
44Common earth for pinking sensor and coolant temperature sensor and absolute pressure sensor
45+ 5 V feed for absolute pressure sensor and throttle position potentiometer
46Common earth for air temperature sensor and throttle position potentiometer
47Not used
48Command (via earth) for fuel pump relay and engine speed information
49Not used
K7M engine
17-45