Page 2 of 181

PETROL INJECTION
Fault finding – Introduction17B
17B-2V12 MR-372-J84-17B000$045.mif
117B
SAGEM 3000
Program No.: A7
Vdiag No.: 44, 48PETROL INJECTION
Fault finding – Introduction
1. SCOPE OF THIS DOCUMENT
This document presents the fault finding method applicable to all computers with the following specifications:
2. PREREQUISITES FOR FAULT FINDING
Documentation type
Fault finding procedures (this document):
– Assisted fault finding (integrated into the diagnostic tool), Dialogys.
Wiring Diagrams:
– Visu-Schéma (CD-ROM), paper.
Type of diagnostic tools
–CLIP
Special tooling required
3. REMINDERS
Procedure
To run fault finding on the vehicle's computers, switch on the ignition in fault finding mode (forced + after ignition
feed).
Proceed as follows:
– with the vehicle card in the card reader,
– press and hold Start button (longer than 5 seconds) with start-up conditions not fulfilled,
– connect the diagnostic tool and perform the required operations.
To cut off the + after ignition feed, proceed as follows:
– disconnect the diagnostic tool,
– press the Start button twice briefly (less than 3 seconds),
– Check that the + after ignition feed has been cut off by checking that the computer warning lights on the instrument
panel have gone out. Vehicle(s): Mégane II / Mégane Sport / Scénic II
Function concerned: Petrol injectionName of computer: Sagem S3000
Program no.: A7
Vdiag No.: 44, 48
Special tooling required
Multimeter
Elé. 1497Bornier
Elé. 1681Universal bornier
Note:
The left-hand and right-hand xenon bulb computers are powered when the dipped headlights are lit.
Fault finding procedures can only be carried out on them after the ignition has been switched on in fault finding
mode (+ after ignition imposed) and the dipped headlights are on.
S3000_V44_PRELI/S3000_V48_PRELI
MR-372-J84-17B000$045.mif
Page 9 of 181

PETROL INJECTION
Fault finding – System operation17B
17B - 9V12 MR-372-J84-17B000$090.mif
SAGEM 3000
Program No.: A7
Vdiag No.: 44, 48
2. OPERATIONAL SAFETY
Warning lights illumination
The S3000 injection system manages the illumination of three warning lights and the issuing of warning messages
according to the severity of the faults detected, to inform the customer and to direct fault finding.
The injection computer manages the illumination of warning lights and warning messages displayed on the instrument
panel. These warning lights illuminate during the starting phase and in the event of an injection fault or engine
overheating.
The warning light illumination signals reach the instrument panel via the multiplex network.
Warning light illumination principle
During the starting phase (START button pressed) the OBD (On Board Diagnostic) warning light comes on for
approximately 3 seconds then goes out.
If there is an injection fault (severity 1), the INJECTION FAULT written message lights up followed by the SERVICE
warning light. It indicates a reduced level of operation and a limited safety level.
The driver should carry out repairs as soon as possible.
Components involved:
– motorised throttle valve,
– accelerator pedal potentiometer,
– inlet manifold pressure sensor,
–computer,
– actuator feed,
– computer feed.
If there is a serious injection fault (severity 2), the red engine symbol and the word STOP appear (display with
information display only), with the ENGINE OVERHEATING written message followed by the STOP warning light
and a buzzer. If this happens, the vehicle must be stopped immediately.
When a fault causing excessive pollution in the exhaust fumes is detected, the orange OBD warning light, an engine
symbol, will be lit:
–flashing in the event of a fault which might irreparably damaged the catalytic converter (destructive misfire). If this
happens you must stop the vehicle immediately,
–constantly in the case of non-compliance with the anti-pollution standards (pollutant misfire, catalytic converter
fault, oxygen sensor faults, inconsistency between the oxygen sensors and canister fault).
Mileage travelled with fault
This parameter serves to measure the distance travelled with one of the injection fault warning lights on: level 1 fault
warning light (amber), coolant temperature overheating warning light, or OBD warning light.
The counter can be reset to 0 using the diagnostic tool.
JSAA741.0
Page 51 of 181

PETROL INJECTION
Fault finding – Interpretation of faults17B
17B-51V12 MR-372-J84-17B000$360.mif
SAGEM 3000
Program No.: A7
Vdiag No.: 44, 48
DF079
PRESENT
OR
STORED
MOTORISED THROTTLE VALVE SERVO
1.DEF : motorised throttle stop search fault
2.DEF : motorised throttle rest position programming error
3.DEF : motorised throttle servo fault
4.DEF : the position memory function does not work
5.DEF : when the throttle bounces off the lower stop, a relatively large permanent
discrepancy can be seen between the set position and actual position of the throttle.
The bounce detection is based on this error. The oscillation fault, after N oscillations
detected, activates the Limp Home defect mode.
6.DEF : when there is a micro-break on gang 1 of the sensor, the voltage delivered
is minimal (0V), which broadly corresponds to complete throttle closure. We can then
see the gang 1 signal lapse in relation to the gang 2 signal, which remains correct.
This lapse speed of one gang in relation to another is used to detect micro-breaks.
The micro-break fault does not activate any defect mode or illuminate any warning
lights.
7.DEF : non-compliance with emission control standards
NOTESPriority for dealing with a combination of faults:
Apply the procedure for dealing with faults DF011 Sensor supply voltage no. 1,
DF078 Throttle potentiometer control circuit, DF095 Throttle potentiometer
circuit gang 1 and DF096 Throttle potentiometer circuit gang 2 first if they are
present or stored.
Conditions for applying the fault finding procedure to stored faults:
The fault is declared present after:
– A change in engine speed.
– the air temperature must be between 5°C and 105°C inclusive.
Special note:
If 1 DEF, 2.DEF or 3.DEF:
– the OBD warning light is lit,
– throttle valve defect mode types 1, 2 and 6.
If 4.DEF or 5.DEF:
– the OBD warning light is lit,
– Throttle valve defect mode types 1, 2, 4 and 6.
Check the cleanliness, condition and fitting of the throttle valve.
Repair if necessary.
If the fault is still present, manually check that the throttle valve rotates correctly.
Repair if necessary.
If the fault is still present, manipulate the harness in order to note a change in fault status (present stored).
Look for possible damage to the wiring harness, check the condition and the connection of the connectors of the
injection computer and motorised throttle valve.
Repair if necessary.
JSAA741.0