13B-9V12 MR-372-J84-13B300$020.mif
DIESEL INJECTION
Fault finding – Cleanliness guidelines13B
EDC16CP33
Program No.: C4
Vdiag No.: 04, 08, 18, 1C,
20, 24, 26, 28, 34, 38, 44,
4C, 54, 58, 5C, 60, 62, 74
II - INSTRUCTIONS TO BE FOLLOWED PRIOR TO ALL OPERATIONS
Check that you have plugs for the unions to be opened (set of plugs available from the Parts Department). The plugs
are single-use only. After use, they must be discarded (once used they are soiled and cleaning is not sufficient to
make them reusable). Unused plugs must be discarded.
Check that you have hermetically resealable plastic bags for storing removed parts. Parts stored in this way will be
less susceptible to the risk of contamination. The bags are to be used once only, and discarded after use.
Use lint-free cleaning cloths (cloth part reference 77 11 211 707). Using normal cloth or paper is prohibited. They are
not lint-free and could contaminate the fuel circuit. A lint-free cloth should only be used once.
Use fresh cleaning agent for each operation (used cleaning agent is contaminated). Pour it into a clean receptacle.
For each operation, use a clean brush in good condition (the brush must not shed its bristles).
Use a brush and cleaning agent to clean the unions to be opened.
Blow compressed air over the cleaned parts (tools, workbench, the parts, unions and injection system zones).
Check that no bristles are left.
Wash your hands before and during the operation if necessary.
When wearing leather protective gloves cover them with latex gloves to prevent contamination. IMPORTANT:
Before carrying out any work on the high pressure injection system, protect:
– the accessories and timing belts,
– the electrical accessories, (starter, alternator, electric power-assisted steering pump),
– the flywheel surface, to prevent any diesel from running onto the clutch friction plate,
– timing chain.
13B-10V12 MR-372-J84-13B300$020.mif
DIESEL INJECTION
Fault finding – Cleanliness guidelines13B
EDC16CP33
Program No.: C4
Vdiag No.: 04, 08, 18, 1C,
20, 24, 26, 28, 34, 38, 44,
4C, 54, 58, 5C, 60, 62, 74
III - INSTRUCTIONS TO BE FOLLOWED DURING THE OPERATION
As soon as the circuit is open, all openings must be plugged to prevent impurities from entering the system. The
plugs to be used are available from the Parts Department. The plugs must not be reused under any circumstances.
Seal the pouch shut, even if it has to be opened shortly afterwards. The ambient atmosphere carries contamination.
All components removed from the injection system must be stored in a hermetically-sealed plastic bag once the
plugs have been inserted.
Using a brush, cleaning agent, air gun, brush or normal cloth is strictly prohibited once the circuit has been opened.
These items could allow contamination to enter the system.
A new component replacing an old one must not be removed from its packaging until it is to be fitted to the vehicle.
13B-11V12 MR-372-J84-13B300$030.mif
13B
EDC16CP33
Program No.: C4
Vdiag No.: 04, 08, 18, 1C,
20, 24, 26, 28, 34, 38, 44,
4C, 54, 58, 5C, 60, 62, 74
System outline
The high pressure injection system is designed to deliver a precise quantity of diesel fuel to the engine at a set
moment.
It is fitted with a BOSCH computer, type EDC16CP33.
The system comprises:
– a priming bulb,
– a diesel filter,
– a high pressure pump,
– a fuel pressure regulator (or actuator) on the high pressure pump (MPROP),
– a fuel pressure regulator (or actuator) mounted on the injector rail (DRV),
– an injector rail,
– a fuel pressure sensor,
– four piezoelectric injectors,
– a diesel temperature sensor,
– a coolant temperature sensor,
– an upstream air temperature sensor,
– a cylinder reference sensor,
– an engine speed sensor,
– a turbocharger pressure sensor,
– an exhaust gas recirculation valve,
– a recycled gas cooling solenoid valve,
– an accelerator pedal potentiometer,
– an atmospheric pressure sensor integrated into the injection computer,
– a flow sensor,
– a turbocharging limiter solenoid valve,
– a damper valve,
– a particle filter,
– a turbo upstream temperature sensor,
– a turbo upstream pressure sensor,
– a particle filter differential pressure sensor,
– a particle filter upstream temperature sensor,
– a particle filter downstream temperature sensor,
– an electric coolant pump (turbocharger),
– four thermoplungers.
The common rail direct high pressure injection system works sequentially (based on the petrol engine
multipoint injection).
This system uses piezoelectric injectors which enable a more precise injection since opening and closing times
are shorter compared to conventional solenoid injectors.
This injection system reduces operating noise, reduces the volume of pollutant gases and particles and produces
high engine torque at low engine speeds thanks to a pre-injection procedure.
The high pressure pump generates the high pressure and transmits it to the injector rail. The actuator located on
the pump controls the quantity of diesel supplied, according to the demand determined by the computer.
The rail supplies each injector through a steel pipe. The actuator located on the injector rail controls the pressure
of diesel fuel in the rail according to the demand determined by the computer.
DIESEL INJECTION
Fault finding – System operation
13B-12V12 MR-372-J84-13B300$030.mif
DIESEL INJECTION
Fault finding – System operation13B
EDC16CP33
Program No.: C4
Vdiag No.: 04, 08, 18, 1C,
20, 24, 26, 28, 34, 38, 44,
4C, 54, 58, 5C, 60, 62, 74
a. The computer:
Determines the injection pressure value necessary for the correct operation of the engine; the pressure can reach
1600 bar in the rail and it must be constantly regulated.
Checks that the pressure value is correct by analysing the value transmitted by the pressure sensor located on
the rail.
Determines the injection duration required to deliver the right quantity of diesel fuel and the moment when injection
should start. Controls each injector electrically and individually after determining these two values.
The quantity of fuel injected is determined by:
– Engine speed (Crankshaft + Cam for synchronisation).
– Accelerator pedal.
– Turbocharging pressure.
– Coolant temperature,
– Inlet air temperature.
–Air flow
– Pressure in the rail.
– Vehicle speed.
The computer manages:
– idling regulation,
– exhaust gas flow reinjection to the inlet,
– fuel supply check (advance, flow and rail pressure),
– the fan assembly control,
– the air conditioning (cold loop function),
– cruise control/speed limiter function,
– pre-post heating control,
– indicator lights control via the multiplex network,
– the operation of the catalysed particle filter,
– turbocharging pressure.
The high pressure pump is supplied at low pressure by an integrated low pressure pump (transfer pump).
It supplies the rail, the pressure in which is regulated by:
–the pressure regulator on the rail (DRV) for starting phases, starting the engine when cold (increase in
temperature to heat the diesel circuit) and when throttling-off,
–the pressure regulator on the pump (MPROP) for all other phases (90% of cases).
As natural leaks in piezoelectric injectors are very low, opening the pressure regulator (DRV) is the only quick
method of dumping the rail pressure and it prevents overpressure when injection is restarted.
The pressure regulator on the pump (MPROP) enables the high pressure pump to supply just the exact quantity
of diesel fuel required to maintain the rail pressure. This component minimises the heat generated and improves
engine output.
Note:
Each piezoelectric injector is connected to the return rail. The injector return rail is kept pressurised by a
mechanical valve at the end of the return rail with a 10 bar calibration (by comparison, solenoid injectors used to
return directly into the common fuel return circuit). This feature is linked to the operation of piezoelectric injectors.
13B-13V12 MR-372-J84-13B300$030.mif
DIESEL INJECTION
Fault finding – System operation13B
EDC16CP33
Program No.: C4
Vdiag No.: 04, 08, 18, 1C,
20, 24, 26, 28, 34, 38, 44,
4C, 54, 58, 5C, 60, 62, 74
Fuel surplus from the pump, injector return rail or rail is collected in a low pressure "octopus manifold" and is then
sent to the fuel filter, providing that the fuel is cold (recirculation), and then to the tank.
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 pressure regulator (or actuator)
on the high pressure pump (MPROP), the fuel pressure regulator (or actuator) on the injector rail (DRV) or the diesel
temperature sensor 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, replace the pressure sensor, the rail and the high pressure pipes.
Some vehicles have a presence sensor mounted in the filter for detecting water in the diesel. If there is water in
the diesel fuel, the orange "Injection and pre-post heating" warning light will come on.
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.
b. The connections between the vehicle's various computers are multiplexed.
The electronic system fitted in this vehicle is multiplexed.
This enables dialogue between the various vehicle computers. As a result:
– the fault warning lights on the instrument panel are lit by the multiplex network,
– 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 sent by the ABS computer via the multiplex network. The vehicle
speed signal is mainly used by the injection computer, the airbag computer and the automatic transmission
computer (if the vehicle is fitted with this).WARNING:
The engine must not operate with:
– Diesel fuel containing more than 10% diester,
– petrol, even in tiny quantities.
Note:
For the M9R 724 (Vdiag 5C and 58):
The engine is limited to 3000 rpm if the vehicle is stationary or if the vehicle speed is less than 4 mph (7 km/h)
and if the engine is warm.
13B-14V12 MR-372-J84-13B300$030.mif
DIESEL INJECTION
Fault finding – System operation13B
EDC16CP33
Program No.: C4
Vdiag No.: 04, 08, 18, 1C,
20, 24, 26, 28, 34, 38, 44,
4C, 54, 58, 5C, 60, 62, 74
c. Functions hosted:
Air conditioning management assistance:
For vehicles with air conditioning, the EDC16CP33 system provides the option of deactivating the air conditioning
via the UCH, under certain conditions of use:
– when requested by the driver,
– when starting the engine,
– if the engine overheats (in order to reduce the power the engine has to supply),
– when the engine speed is kept at a very high level (to protect the compressor),
– during transition phases (e.g. under heavy acceleration when overtaking, anti-stalling and moving off strategies).
These conditions are only taken into account when they do not occur repeatedly, in order to prevent system
instabilities (erratic deactivations),
– when certain faults appear.
I - Cold loop air conditioning management:
The air conditioning is the cold loop type and its management shared between several computers.
The injection computer is responsible for:
– authorising requests for cold air depending on the engine coolant temperature and the engine speed,
– calculating the power absorbed by the compressor from the refrigerant pressure.
–requesting fan assembly actuation (Mégane II ph2 and Scénic II ph2) and controlling fan assembly actuation
(Laguna II, Vel Satis ph2 and Espace IV ph2), according to the vehicle speed, the refrigerant pressure and the
engine coolant temperature.
The driver requests the air conditioning to be switched on by means of the ventilation selector coupled to a switch.
The cold air request is authorised or denied depending on the pressure measured. If this pressure is outside the
operating limits, the cold loop program is not activated.
The air conditioning system is authorised by the injection computer 2 to 8 seconds after the engine is started.
Management of the thermoplungers:
To improve cold starting, the vehicle is fitted with thermoplungers. These thermoplungers are managed and
controlled by the injection computer, according to the operating phases, primarily to accelerate the increase in
engine coolant temperature.
The maximum number of thermoplungers that can be actuated is four and their actuation depends mainly on the
coolant temperature and the air temperature.
See configuration reading LC056 Thermoplungers: WITH or WITHOUT.
When necessary, they are actuated by the injection system only during particle filter regeneration by means
of a special unit.
The maximum number of thermoplungers that can be managed is four and their activation depends mainly on the
coolant temperature (< 15°C) and air temperature (< 5°C).
13B-15V12 MR-372-J84-13B300$030.mif
DIESEL INJECTION
Fault finding – System operation13B
EDC16CP33
Program No.: C4
Vdiag No.: 04, 08, 18, 1C,
20, 24, 26, 28, 34, 38, 44,
4C, 54, 58, 5C, 60, 62, 74
II - Cruise control/speed limiter management:
The cruise control function, when activated, allows you to keep the vehicle speed at a selected value
regardless of the driving conditions encountered.
Using the control buttons, the driver can increase or reduce the speed of the vehicle.
If the driver wishes to exceed the cruising speed, he may:
– press the accelerator pedal and exceed the cruising speed (the vehicle will return to the initial cruising speed
once the driver takes his foot off the pedal),
– press the system control buttons.
The cruise control function can be deselected either by:
– the system control buttons,
– deactivating the cruise control switch,
– when system events are detected, such as the brake pedal or clutch being pressed,
– when system errors are detected such as an inconsistent vehicle speed.
The cruise control function can also be temporarily disabled when the driver wants to increase the speed by
depressing the accelerator pedal. The cruising speed is resumed when the driver releases the accelerator pedal.
The vehicle will then attempt to reach the cruising speed at a controlled acceleration rate.
It is possible to reactivate the vehicle speed control and resume the last cruising speed after deactivation
(computer supply not cut off).
When activated (using the selection switch) the vehicle speed limiter function limits the vehicle speed to a
preselected value. The driver controls the vehicle in the normal way using the accelerator pedal until the cruising
speed is reached.
If the driver attempts to exceed this speed, the system ignores the pedal request and controls the vehicle speed
in the same way as the cruise control function, as long as the accelerator pedal is kept sufficiently depressed.
As with cruise control, the cruising speed can be altered using the one-touch control buttons or by pressing
and holding.
For safety reasons, it is possible to exceed the cruising speed by depressing the accelerator pedal beyond the pedal
position limiting value. The vehicle speed is fully controlled through pedal position, until the vehicle speed falls back
below the limit speed when the speed limiter function will once again be reactivated.
If the driver wishes to exceed the cruising speed, he may:
– exceed the accelerator pedal's kickdown point,
– increase it by pressing or pressing and holding the switch.
The speed limiter function can be deselected either:
– the system control buttons,
– by switching off the speed limiter switch,
– when system events are detected, such as the brake pedal or clutch being pressed,
– when system errors are detected such as an inconsistent vehicle speed.
13B-16V12 MR-372-J84-13B300$030.mif
DIESEL INJECTION
Fault finding – System operation13B
EDC16CP33
Program No.: C4
Vdiag No.: 04, 08, 18, 1C,
20, 24, 26, 28, 34, 38, 44,
4C, 54, 58, 5C, 60, 62, 74
III - Management of the damper valve
The damper valve is now responsible for two functions:
– Damping: when the engine is switched off, the flap closes in order to block the passage of air towards the cylinders.
The aim of this is to stop the engine as quickly as possible and to reduce instabilities when the engine is switched
off.
– "Valving" function depending on the engine operation: the damper valve closes by a few % to create a "venturi"
effect at the EGR valve passage section.
The aim of this is to accelerate the air flow of EGR gases and to reduce the emission of pollutants.
IV - Exhaust gas recirculation management
The EGR (Exhaust Gas Recirculation) system involves removing exhaust gases and reintroducing them into the
inlet.
This system plays a major role in reducing diesel engine emissions. The EGR system is cooled by a gas - water
exchanger, as on most Euro IV engines. This cooler has a dual position bypass valve, which allows the gas to be
cooled or not depending on the emission control requirements. The bypass circuit is inside the cooler (not visible
from the outside). The valve control rod is visible from the outside.
The exhaust gases are collected in the exhaust manifold (before the turbocharger), then directed to the EGR cooler
and the EGR valve. The EGR valve connects the air circuit between the damper valve and the inlet manifold; the
EGR valve is positioned next to the damper valve.
The EGR valve is activated every time the engine stops by performing 10opening/closing cycles. This programming
activates the EGR valve in order to prevent it from clogging. The program is no longer active if there are any system
faults.
The EGR system does not operate below 5°C (air flowmeter temperature).
– The controlled EGR cooler bypass
The EGR cooler bypass is controlled by an all-or-nothing solenoid valve, connected on one side to the vacuum
pump, and on the other side to the bypass control diaphragm. It is actuated according to the coolant temperature
and the engine operating status. Gases flow into the EGR section of the cooler unless the engine is cold, in which
case they flow through the bypass valve. There is also a regular actuation function for the bypass valve to prevent it
from clogging.
– EGR valve
The EGR valve is supplied by direct current and connected to a potentiometer copying the position of the valve.
The opening of the valve is actuated (H bridge) by a positive command 0 to 100%.
The valve is controlled using a double regulation loop.
The first loop (fastest) is a position loop. It brings the valve to the desired position by a loop connection using the
signal from the position sensor.
The second loop is slower and is an air flow loop. At a given operating point, the air flow setpoint is attained by
adjusting the quantity of exhaust gas flowing through the EGR valve and the flow of fresh air passing through the
damper valve. At a total constant flow, the more exhaust gas recirculation, the less fresh air there is and vice versa.
The air flow is measured by the flowmeter and the setpoint is attained using both the EGR valve position setpoint
and the damper valve position setpoint.