DIESEL INJECTION
Fault finding – Introduction13B
13B - 2V3 MR-372-J84-13B250$045.mif
113B
EDC16
PROGRAM No: C1
Vdiag No.: 51DIESEL INJECTION
Fault finding – Introduction
1. SCOPE OF THIS DOCUMENT
This document presents the fault finding procedure applicable to all computers with the following specifications:
2. PREREQUISITES FOR FAULT FINDING
Documentation type
Fault finding procedures (this manual):
–Assisted fault finding (integrated into the diagnostic tool), Dialogys.
Wiring Diagrams:
–Visu-Schéma (CD-ROM), paper version.
Type of diagnostic tools
–CLIP + CAN sensor
Special tooling required
3. RECAP
Procedure
To run fault finding on the vehicle's computers, switch on the ignition in fault finding mode (forced + after ignition
feed).
–vehicle's card in reader;
–press and hold the Start button (longer than 5 seconds) with start-up conditions not present,
–connect the diagnostic tool and perform the required operations.
To cut off the + after ignition feed, proceed as follows:
–disconnect the diagnostic tool,
–vehicle card in reader,
–press the Start button twice briefly (less than 3 seconds),
–ensure that the + after ignition feed has been cut off by checking that the computer indicator lights on the
instrument panel have gone out. Vehicle(s): MEGANE II, SCENIC II
Engine type and suffix: F9Q 804
Function concerned: DIESEL INJECTIONName of computer: BOSCH EDC16 C3
Program no.: C1
Vdiag No.: 51
Special tooling required
Multimeter
+ Elé. 1590Computer connection bornier
Or Elé. 1681Universal bornier
EDC16_V51_PRELI
MR-372-J84-13B250$045.mif
DIESEL INJECTION
Fault finding – System operation13B
13B - 10V3 MR-372-J84-13B250$135.mif
EDC16
PROGRAM No: C1
Vdiag No.: 51
a) The computer:
Determines the value of injection pressure necessary for the engine to operate correctly and then controls the
pressure regulator.
Checks that the pressure value is correct by analysing the value transmitted by the pressure sensor located on the rail.
Determines the injection duration necessary for supplying the correct quantity of diesel and the moment when
injection is required; controls each injector electrically and individually after determining these values.
The flow injected into the engine is determined by:
–the duration of injector control,
–the rail pressure (regulated by the computer),
–the injector opening and closing speed,
–the needle stroke (determined by a constant for the type of injector),
–the nominal hydraulic flow of the injector (specific to each injector).
The computer manages:
–idling regulation,
–exhaust gas flow reinjection to the inlet (EGR),
–fuel supply check (advance, flow and rail pressure),
–the CMV control via the Protection and Switching Unit (centralised coolant temperature management function),
–the air conditioning (cold loop function),
–the cruise control/speed limiter function,
–pre-post heating control,
–fault warning lights via the multiplex network.
The high pressure pump is supplied at low pressure by an integrated low pressure pump (transfer pump).
It supplies the rail, the pressure of which is controlled by the fuel flow actuator (MPROP) for charging, and for
discharging by the injector valves. This compensates for pressure drops. The fuel flow actuator enables the high
pressure pump to supply the exact quantity of diesel fuel required to maintain the rail pressure. This component
minimises the heat generated and improves engine output. In order to discharge the rail using the injector valves, the
valves are controlled by brief electrical pulses which are:
–short enough not to open the injector (passing through the feedback circuit from the injectors),
–long enough to open the valves and discharge the rail.
DIESEL INJECTION
Fault finding – System operation13B
13B - 11V3 MR-372-J84-13B250$135.mif
EDC16
PROGRAM No: C1
Vdiag No.: 51
b) Multiplex connection between the different vehicle computers.
The electronic system fitted in this vehicle is multiplexed.
This enables dialogue between the various vehicle computers. As a result:
–the activation of the fault warning lights on the instrument panel is performed by the multiplex network, with the
vehicle speed sensor on the gearbox deactivated,
–vehicle faults are displayed by the multiplex network,
–the vehicle speed sensor on the gearbox is not needed.
The vehicle speed signal on the instrument panel is transmitted by the ABS computer via a wire connection, then
sent out on the multiplex network by the instrument panel. The vehicle speed signal is used mainly by the injection
computer and the airbag computer.
Some vehicles have adopted a sensor for detecting water in the diesel fuel, located in the filter. If there is water in the
diesel fuel, the orange "Injection and pre-post heating" warning light will come on.
The system can inject diesel fuel into the engine at a pressure of up to 1600 bar. Before each operation, check that
the injector rail is depressurised and that the fuel temperature is not too high.
You must respect the cleanliness guidelines and safety advice specified in this document for any work on the high
pressure injection system.
Removal of the internal parts of the pump and injectors is prohibited. Only the fuel flow actuator, the diesel fuel
temperature sensor and the venturi can be replaced.
For safety reasons, it is strictly prohibited to undo a high pressure pipe union when the engine is running.
It is not possible to remove the pressure sensor from the fuel rail because this may cause circuit contamination
faults. If the pressure sensor fails, the pressure sensor, the rail and the five high pressure pipes must be replaced.
It is forbidden to remove any injection pump pulley bearing the number 070 575. If the pump needs to be replaced,
replace the pulley.
Supplying + 12 V directly to any component in the system is prohibited.
Ultrasonic decoking and cleaning are prohibited.
Never start the engine unless the battery is connected correctly.
Disconnect the injection computer when carrying out any welding work on the vehicle.WARNING
The engine must not operate with:
–Diesel fuel containing more than 10 % diester,
–petrol, even in tiny quantities.
DIESEL INJECTION
Fault finding – System operation13B
13B - 14V3 MR-372-J84-13B250$135.mif
EDC16
PROGRAM No: C1
Vdiag No.: 51
Exhaust gas recirculation management
The exhaust gas recirculation system comprises a direct current EGR valve controlled by an H bridge in the
computer. This system has a built-in valve position feedback potentiometer.
The EGR valve is controlled in a closed loop on the change in the air flow measured by the flow sensor.
The potentiometer is used in the fault finding procedure for the EGR valve position.
Warning light management:
Instrument panel display
The computer manages the data display on the instrument panel relating to engine operation. This involves six
functions:
–the pre-postheating warning light,
–the coolant temperature warning light or warning message;
–the fault level 1 warning light (non-critical fault),
–the fault level 2 warning light (emergency stop),
–the OBD warning light (European On Board Diagnostic).
These five functions are represented by 4 or 5 warning lights and/or messages sent by the trip computer.
A 3 second visual inspection is carried out by the injection computer when ignition is switched on (automatic
procedure for test managed by the instrument panel).
Orange Pre-post heating/non-critical fault SERVICE warning light (level 1)
This light is used both as an in-operation indicator light and as a system fault indicator:
–Continuously lit with + after ignition feed:
Indicates preheating of the spark plugs.
–Continuous lighting accompanied by the message CHECK INJECTION or ELECTRONIC FAULT:
Indicates a level 1 fault (implies operation in injection system defect mode).
The driver should carry out repairs as soon as possible.
Temperature warning light/red EMERGENCY STOP (level 2)
This indicator light is used both as an in-operation indicator light and as a system fault warning light. Lights up for
3 seconds when the ignition is switched on (automatic test procedure managed by the instrument panel):
–Continuously lit or alternately lit with ENGINE OVERHEATING message:
Indicates engine overheating (the driver is free to choose whether or not to stop the vehicle).
–Continuously lit with the FAULTY INJECTION message:
Indicates a level 2 fault (In this case, the injection is automatically cut after a few seconds).
The driver should carry out repairs as soon as possible.
ORANGE OBD excess pollution warning light
An engine symbol accompanied by the message CHECK EMISSION CONTROL.
This warning light comes on if the system has one or more OBD faults.
This warning light is used to warn the driver of injection faults leading to excessive pollution or that the EOBD* system
has been deactivated.
The injection computer requests activation of the OBD warning light for a present fault only after three successive
driving cycles.
A 3 second visual inspection is carried out by the injection computer when ignition is switched on (automatic
procedure for test managed by the instrument panel).
*EOBD: Electronic on board diagnostics.
DIESEL INJECTION
Fault finding – Interpretation of faults13B
13B-30V3 MR-372-J84-13B250$315.mif
DF001
PRESENT
OR
STOREDCOOLANT TEMPERATURE SENSOR CIRCUIT
CC.0 : Short circuit to earth
CO.1 : Short circuit or open circuit to + 12 V
NOTESConditions for applying the fault finding procedure to stored faults:
The fault is declared present:
–when an attempt is made to start the engine,
–when the engine is running.
Special notes:
If the fault is present:
–the coolant temperature: PR064 Coolant temperature is fixed at 119˚C,
–the preheating phase is greater than 10 seconds,
–the low speed motor-driven fan assembly (GMV 1) is continuously supplied,
–if there is a fault with GMV 1, then start GMV 2 for vehicles with air conditioning.
–the level 1 warning light is lit,
–the OBD warning light will illuminate after three consecutive driving cycles (starting
+ 5 seconds + switching off the ignition and waiting 1 minute).
Use bornier Ele. 1681 or Ele. 1590 for all operations on the computer connectors.
Check the connections of the coolant temperature sensor 4-track connector.
Check the injection computer connections.
Repair if necessary.
Measure the resistance of the coolant temperature sensor between tracks 2 and 3 of its black connector.
Replace the sensor if its resistance is not approximately:
75780 ± 7000 Ω at - 40˚C
12460 ± 122 Ω at - 10˚C
2252 ± 112 Ω at 25˚C
811 ± 39 Ω at 50˚C
283 ± 8 Ω at 80˚C
115 ± 3 Ω at 110˚C
87 ± 2 Ω at 120˚C
Check the insulation, continuity and the absence of interference resistance on the following connections:
Injection computer brown 48-track connector B
track F2Track 3 coolant temperature sensor
Injection computer brown 48-track connector B
track H1Track 2 coolant temperature sensor
Repair if necessary.
If the fault is still present, replace the coolant temperature sensor.
AFTER REPAIRDeal with any faults.
Carry out a road test followed by another check with the diagnostic tool.
EDC16
PROGRAM No.: C1
Vdiag No.: 51DIESEL INJECTION
Fault finding – Interpretation of faults
EDC16_V51_DF001
DIESEL INJECTION
Fault finding – Interpretation of faults13B
13B-31V3 MR-372-J84-13B250$315.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
DF003
PRESENT
OR
STOREDATMOSPHERIC PRESSURE SENSOR CIRCUIT
1.DEF : Signal outside upper limit
2.DEF : Signal outside lower limit
3.DEF : Inconsistent signal
NOTESConditions for applying the fault finding procedure to stored faults:
The fault is declared present:
–when an attempt is made to start the engine,
–when the engine is running.
Special notes:
The atmospheric pressure sensor is integrated into the injection computer and cannot
be separated.
If the fault is present:
–there is light smoke at the exhaust,
–the atmospheric pressure value changes to safe mode, PR035 Atmospheric
pressure = 750 mbar.
–the level 1 warning light is lit,
–the OBD warning light will come on after three consecutive driving cycles (starting
+ 5 seconds + switching off the ignition and waiting 1 minute).
Use bornier Ele. 1681 or Ele. 1590 for all operations on the computer connectors.
Disconnect the injection computer and check the condition of the contacts and connector.
Repair if necessary.
Display the value of parameter PR041 Turbocharger pressure.
If this value is stuck at 750 mbar, refer to interpretation of fault DF004 Turbocharging pressure sensor circuit.
If the fault is still present, contact the Techline.
AFTER REPAIRDeal with any faults.
Carry out a road test followed by another check with the diagnostic tool.
EDC16_V51_DF003
DIESEL INJECTION
Fault finding – Interpretation of faults13B
13B-32V3 MR-372-J84-13B250$315.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
DF004
PRESENT
OR
STOREDTURBOCHARGING PRESSURE SENSOR CIRCUIT
CO.0 : Open circuit or short circuit to earth
CC.1 : Short circuit to + 12 V
1.DEF : Inconsistency of the signal
NOTESConditions for applying the fault finding procedure to stored faults:
The fault is declared present:
–when an attempt is made to start the engine,
–when the engine is running.
Special notes:
If the fault is present:
–the EGR function is inhibited,
–the turbocharging pressure sensor is in defect mode, PR041 = 750 mbar,
–the level 1 warning light is lit.
Use bornier Ele. 1681 or Ele. 1590 for any operation on the injection computer
connectors.
Order of priority in the event of more than one fault:
Deal with fault DF011 Sensor supply voltage no. 1 first if it is present or stored.
CO.0
NOTESNone
Check the turbocharger pressure sensor connections.
Check the injection computer connections.
Repair if necessary.
Check the continuity and insulation against earth of the following connections:
Injection computer brown 48-track connector B,
track G4Track 3 turbocharging pressure sensor
connector
Injection computer brown 48-track connector B,
track K2Track 4 turbocharger pressure sensor connector
Repair if necessary.
If the fault is still present, replace the turbocharging pressure sensor.
AFTER REPAIRDeal with any faults.
Carry out a road test followed by another check with the diagnostic tool.
EDC16_V51_DF004
DIESEL INJECTION
Fault finding – Interpretation of faults13B
13B-35V3 MR-372-J84-13B250$315.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
DF005
PRESENT
OR
STOREDENGINE SPEED SENSOR CIRCUIT
1.DEF : No signal
2.DEF : Inconsistent signal
NOTESConditions for applying the fault finding procedure to a stored fault:
The fault is declared present:
–when an attempt is made to start the engine,
–when the engine is running.
Special notes:
Use bornier Ele. 1681 or Ele. 1590 for all operations on the computer connectors.
The engine speed sensor is consistent with the camshaft sensor.
If the fault is present:
–it is impossible to start the engine or the engine stops,
–the level 2 warning light is lit.
Check the engine speed sensor connections.
Check the injection computer connections.
If one of the connectors is faulty and there is a repair procedure (see Technical Note 6015A, Electrical wiring
repair, Wiring: Precautions for repair), repair the connector, otherwise replace the wiring.
Check that the sensor is correctly mounted and that the flywheel target is not damaged.
Check that the gap between the engine speed sensor and the flywheel is 0.5 to 1.8 mm.
Measure the resistance of the engine speed sensor between terminals A and B of its black connector.
If the winding resistance is not between 510 Ω and 850 Ω at an engine temperature of 20˚C, replace the engine
speed sensor.
Check for continuity and the absence of interference resistance of the following connections:
Injection computer brown 48-track connector B
track B1Track A engine speed sensor
Injection computer brown 48-track connector B
track C1Track B engine speed sensor
If the connection or connections are faulty and there is a repair method (see Technical Note 6015A, Repairing
electrical wiring, Wiring: Precautions for repair), repair the wiring, otherwise replace it.
Repair if necessary.
If the fault is still present, contact the Techline.
AFTER REPAIRDeal with any faults.
Carry out a road test followed by another check with the diagnostic tool.
EDC16_V51_DF005