2011 RENAULT SCENIC coolant pump

13B-8V4 MR-372-J84-13B000$020.mif
13B
DDCR INJECTION
Vdiag No.: 44, 48
System outline
The DDCR injection system used on the K9 engine is an electronically managed high pressure injection system.
The fuel is compressed by a high pressure pump then stored in a rail that feeds the injectors. Injection occurs when
a current pulse is applied to the injector holders. The injected flow is proportional to the rail pressure and to
the applied pulse length, and the start of injection is phased with the start of the pulse.
The circuit comprises two subsystems, which are distinguished by the fuel pressure level.
– The low pressure system includes the tank, diesel fuel filter, transfer pump and injector holder return pipes.
– The high pressure circuit contains the high pressure pump, the rail, the injector holders and the high pressure tubes.
Finally, there are a certain number of sensors and regulating actuators for controlling and monitoring the entire
system.
Functions provided
Function: Fuel supply management (timing, flow and pressure).
Quantity of fuel injected and injection timing adjustment
The injection checking parameters are the quantities to be injected and their respective timing. These are calculated
by the computer using signals from the following sensors:
• Engine speed (Crankshaft + Cam for synchronisation)
• Accelerator pedal
• Turbocharging pressure and air temperature (Turbocharger pressure)
• Coolant temperature
• Air temperature
• Air load (Flow and Pressure)
• Rail pressure
• Flowmeter
• Turbocharging solenoid valve
The quantities to be injected and their respective timing are converted into:
• a reference tooth
• the time between this tooth and the start of the pulse
• the time for which the supply to the injector holder is on
An electrical current (pulse) is sent to each injector holder according to previously calculated data. The system
makes one or two injections (1 pilot injection, 1 main injection). The general principle is to calculate an overall
injected flow which will then be divided into a main injection flow and a pilot injection flow, to help the combustion
process work properly and to reduce pollutant emissions.
An accelerometer is used to monitor some of the fuel injection deviation. This has several roles:
• Protecting the engine by detecting injection leaks (disabled on the basic vehicle).
• Checking the pilot quantity by measuring deviation and dispersion
• By changing both the duration and timing of the injection, the quantity of fuel injected and the mixture ignition timing
can be adjusted.
DIESEL INJECTION
Fault finding – System operation

13B-9V4 MR-372-J84-13B000$020.mif
DIESEL INJECTION
Fault finding – System operation13B
DDCR INJECTION
Vdiag No.: 44, 48
Rail pressure check
The quality of combustion is influenced by the size of the atomised droplets in the cylinder. In the combustion
chamber, smaller fuel droplets will have time to burn fully, and will not produce smoke or unburned particles. To
meet the pollution requirements, the droplet size, and therefore the size of the injection holes, must be reduced.
With smaller holes, less fuel will be able to be introduced at a given pressure, which limits the power. To handle this
drawback, the injected fuel flow has to be increased, which means a pressure increase (and more apertures on the
injector nozzles). For the DDCR injection system, the pressure reaches 1400 bar in the rail, and must be constantly
regulated. The measuring circuit consists of an active pressure sensor on the rail connected to an analogue port on
the computer.
The High Pressure pump is supplied at low pressure (5bar) by a built-in transfer pump. This pump supplies the rail.
The rail filling pressure is controlled by the filling valve (IMV) and the discharge pressure is controlled by the injector
valves. This compensates for pressure drops. The filling actuator enables the high pressure pump to supply just
the exact quantity of diesel fuel required to maintain the rail pressure. This mechanism minimises the heat
generated and improves engine output.
In order to discharge the rail using the injector valves, the valves are actuated by short electrical pulses which are:
– short enough not to open the injector (and pass through the return circuit from the injectors),
– long enough to open the valves and discharge the rail.
The fuel surplus is sent back to the fuel filter or the tank, according to its flow. If there is no IMV control, the rail
pressure is limited by a discharge valve fitted on the pump.
Idling speed regulation
The computer handles the calculation of idling speed. This has to take account of the instantaneous power level to
be supplied, according to the following factors:
– Engine coolant temperature
– Gear engaged
– Battery charging
– Electrical consumers (Heating elements, Air conditioning, Fan assembly, Heated windscreen, etc.) active or
inactive
Individual injector correction (C2I)
The DDCR system injectors must be calibrated with corrective values to adjust their flow precisely. Each injector is
calibrated for different pressures on a test bench, and its specifications are shown on a label attached to the body of
the injector holders. These individual correction values are then written to the computer EEPROM, which can then
actuate the injectors by taking into account their manufacturing dispersion.

13B-18V4 MR-372-J84-13B000$030.mif
13B
DDCR INJECTION
Vdiag No.: 44, 48
COMPUTER REPLACEMENT, PROGRAMMING AND REPROGRAMMING OPERATIONS
Before reprogramming or removing the computer in After-Sales operations, save the following data to the
diagnostic tool:
– The C2I parameters (individual injector correction) and the engine adaptives using command SC003 Save
computer data.
The system can be reprogrammed with the diagnostic socket using the RENAULT CLIP diagnostic tool
(Consult Technical Note 3585A, Computer programming and reprogramming procedure, and follow the
instructions given by the diagnostic tool).
Any time the computer has been reprogrammed
– Use the diagnostic tool command SC001 Enter saved data to restore the C2I and the engine adaptives.
– Use command AC028 Static test to reinitialise the computer (fan assembly, etc.).
– When changing the pump, refer to the high pressure pump replacement procedure (consult Technical Note 5011A,
Repriming Delphi high pressure pumps on K9K engines).
– Switch the ignition off and then on again.
–Activate the starter without releasing the key until the engine starts (the engine start time can be up to 20
seconds).
– Stop the engine (to initialise the computer) and wait 30 seconds.
– Switch the ignition on again and use the diagnostic tool to carry out the following steps:
– Run command VP010 Enter VIN.
– After injection system programming, stored faults may appear on other computers. Clear the memory of these
computers. IMPORTANT:
Before reprogramming the injection computer, move the main Cruise control/Speed limiter switch to the rest
position. The information about the cruise control or the speed limiter displayed on the instrument panel
disappears.
Otherwise, if the main switch remains in the cruise control or speed limiter position during and after reprogramming,
the Cruise control/Speed limiter function will not be operational.
The procedure for resetting the function is as follows:
Vehicle ignition on.
Main switch in rest position (the computer then detects the rest position).
Switch in Cruise control position to activate the Cruise control function.
Switch in Speed limiter position to activate the Speed limiter function.
IMPORTANT
– Switch on the diagnostic tool (mains or cigarette lighter supply).
– Connect a battery charger.
– Switch off all electrical consumers (lights, interior lights, air conditioning, radio/CD, etc.).
– Wait for the engine to cool (engine coolant temperature below 60°C and air temperature below 50°C).
DIESEL INJECTION
Fault finding – Replacement of components

13B-152V4 MR-372-J84-13B000$120.mif
DIESEL INJECTION
Fault finding – Tests13B
DDCR INJECTION
Vdiag No.: 44, 48
IMV = fuel flow actuator
TEST 6 High pressure system check
NOTESSpecial note:
Certain faults make it impossible to carry out this test - deal with these first.
IMPORTANT: It is pointless and dangerous to engage the starter motor for more
than 5 seconds.
Preliminary Checks:
– Check for the presence of fuel
– Check that there is no air in the low pressure circuit. Run TEST 1: Low pressure circuit check.
– Ensure that the correct fuel is being used. Run TEST 13 Diesel fuel conformity check.
It is possible to check the high pressure supply pump capacity by carrying out the following procedure:
–With the ignition off, disconnect the low pressure actuator from the pump (IMV brown connector) and connect
a test IMV or the MOT. 1711 adapter.
– Electrically disconnect the four injectors.
– Switch on the ignition, connect the diagnostic tool and re-establish dialogue with the injection system.
– Go to the Main computer statuses and parameters screen.
– Run the test cold, PR064 Coolant temperature < 30°C or equal to the ambient temperature.
– Engage the starter for 5 seconds.
– Read the rail pressure maximum value (PR038) during the test on the diagnostic tool.
Is the rail pressure greater than 1050 bar?
A
NO
B
YES
DDCR_V44_TEST06/DDCR_V48_TEST06

13B-155V4 MR-372-J84-13B000$120.mif
DIESEL INJECTION
Fault finding – Tests13B
DDCR INJECTION
Vdiag No.: 44, 48
TEST 8 Injector return flow
NOTESSpecial note:
Certain faults make it impossible to carry out this test - deal with these first.
Does the engine start?
Command AC029 also checks the return volume of each injector to detect an internal injector leak.
Be careful with any objects (tool or other) on the engine housing during the four cycles of the operation
(possible vibrations).
Tooling required
–Mot. 1711 Injector flow measuring kit.
Or: Use four pipes with internal diameter 4mm and approximately 50 cm in length, and four graduated measuring
cylinders.
Procedure
– Ensure that the engine coolant temperature is above 60°C,
– switch off the ignition,
– disconnect the return pipes from the four injectors,
– cap the pump venturi tube to prevent the low-pressure circuit from depriming,
– connect the four transparent tubes in place of the return pipes,
– put the other ends of the four pipes into four graduated measuring cylinders.
– After finishing these preparations, start the engine and let it idle for 2 minutes.
Note: This idle time must be respected for the test results to be interpreted correctly.
–Run command AC029 High pressure circuit sealing check
.The engine will automatically carry out a cycle of four accelerations to increase the rail pressure and measure the
internal injector leaks under these conditions.
–Once the cycle is complete, run command AC029 again to obtain a correct reading of the return volume of
each injector.
– Switch off the engine at the end of the cycle.
NOA
YES
DDCR_V44_TEST08/DDCR_V48_TEST08