13B-6V4 MR-372-J84-13B000$010.mif
DIESEL INJECTION
Fault finding – Introduction13B
DDCR INJECTION
Vdiag No.: 44, 48
You will always be asked for this log:
• when requesting technical assistance from the Techline,
• when requesting approval before replacing parts for which approval is compulsory,
• to be attached to monitored parts for which reimbursement is requested. The log is needed for warranty
reimbursement, and enables better analysis of the parts removed.
6. SAFETY INSTRUCTIONS
Safety rules must be observed during any work on a component to prevent any material damage or personal injury:
– check the battery voltage to avoid incorrect operation of computer functions,
– use the proper tools.
7. CLEANLINESS INSTRUCTIONS WHICH MUST BE FOLLOWED WHEN WORKING ON THE HIGH-
PRESSURE DIRECT INJECTION SYSTEM
Risks relating to contamination:
The high pressure direct injection system is highly sensitive to contamination. The risks associated with
contamination are:
– damage to or destruction of the high pressure injection system,
– components jamming,
– a component leaking.
All After-Sales operations must be performed under very clean conditions. This means that no impurities
(particles a few microns in size) should penetrate the system during dismantling.
The cleanliness principle must be applied from the filter to the injectors.
What are the sources of contamination?
– metal or plastic swarf,
– paint,
– fibres from cardboard, brushes, paper, clothing and cloth.
– foreign bodies such as hair,
– ambient air,
–etc.WARNING
BEFORE CARRYING OUT ANY WORK ON THE INJECTION SYSTEM, CHECK WITH THE DIAGNOSTIC
TOOL:
– that the rail is depressurised,
– that the fuel temperature is not too high.
IMPORTANT
Cleaning the engine using a high pressure washer is prohibited because of the risk of damaging connections. In
addition, moisture may collect in the connectors and create electrical connection faults.
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-11V4 MR-372-J84-13B000$020.mif
DIESEL INJECTION
Fault finding – System operation13B
DDCR INJECTION
Vdiag No.: 44, 48
WITH FLOWMETER (K9K 728)
The flow of fresh air entering the engine is given by a hot wire ratiometric sensor. This flow sensor is used to
manage the amount of exhaust gas to be recirculated to ensure optimum recirculation rates. A fresh air temperature
sensor is built into the flowmeter.
Air flow measurement allows closed-loop control via the EGR valve.
Besides electrical faults with the sensor, there is a consistency test between the measured air flow and an estimated
air flow without EGR.
This flow evaluates the amount of fresh inlet air, based on the values supplied by the surrounding systems:
– the inlet air temperature measured by a sensor located after the turbocharger and/or after the intercooler (if fitted),
– the turbocharging pressure,
– the engine speed.
Pre-postheating actuation
Pre-postheating actuation consists of controlling the heater plugs and preheating warning light on the instrument
panel. The heater plugs are activated by relays, and the power is supplied from the battery. After the ignition is
switched on. Preheating is activated for a period of time. The warning light is illuminated for an activation period that
depends on the battery voltage, the atmospheric pressure, and the coolant temperature. When the temperature is
below a certain threshold, a postheating function can be used to improve the combustion stability, and consequently
engine operation (reducing unburnt particles and pollutant emissions).
Turbocharger control solenoid valve actuation
The turbocharger system comprises a solenoid valve that is used to actuate the vanes (or wastegate) to create an
overpressure or a vacuum in the inlet circuit.
13B-17V4 MR-372-J84-13B000$020.mif
DIESEL INJECTION
Fault finding – System operation13B
DDCR INJECTION
Vdiag No.: 44, 48
32-TRACK GREY CONNECTOR C
Description Tracks Tracks Description
Not used A1 E1 Not used
Water in diesel fuel detector earth A2 E2 Not used
Not used A3 E3 Not used
Not used A4 E4 Not used
Not used B1 F1 Supply relay control
Not used B2 F2 Preheating relay control
Water in diesel fuel detector signal B3 F3 Not used
Not used B4 F4 Not used
Not used C1 G1 Not used
Not used C2 G2 After relay + battery 1 earth
Refrigerant pressure sensor signal C3 G3 Refrigerant pressure sensor earth
Refrigerant pressure sensor supply C4 G4 Not used
Not used D1 H1 Potentiometer earth Gang 1
Not used D2 H2 Not used
Heater plug diag signal D3 H3 After relay + battery 2
Not used D4 H4 Not used
NOTE:
The supply voltage on tracks G2 and H2 is not measurable when the computer connector is disconnected.
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-19V4 MR-372-J84-13B000$030.mif
DIESEL INJECTION
Fault finding – Replacement of components13B
DDCR INJECTION
Vdiag No.: 44, 48
REPLACING THE INJECTORS:
The system may be configured via the diagnostic socket using the RENAULT CLIP diagnostic tool.
The C2I parameters must be replaced after replacing an injector/injectors.
To do this, reprogram the C2I into the computer using the following commands:
Cylinder 1 injector: command VP001 Cylinder 1 injector code (cylinder at flywheel end).
Cylinder 2 injector: command VP002 Cylinder 2 injector code.
Cylinder 3 injector: command VP003 Cylinder 3 injector code.
Cylinder 4 injector: command VP004 Cylinder 4 injector code.
It is also possible to enter the four C2I using command SC002 Enter injector codes.
The technician can use the appropriate command to re-enter the new C2I for the replaced injector and to erase the
old C2I.
–Only after simultaneously replacing at least three injectors, reset the injector programming adaptives, using
command RZ004 Pressure regulation programming adaptives. IMPORTANT
AFTER A PROGRAMMING OPERATION, DO NOT CONNECT THE BATTERY FOR AT LEAST 30 minutes (to
carry out other work on the vehicle).
Note:
If commands SC001 and SC003 have been lost or if they are not operating after programming the computer:
– Enter the C2I for each injector manually, by reading the C2I on each injector (see Replacement of
components, Injector replacement).
– Use command AC028 Static test to reinitialise the computer (fan assembly, etc.).
– Switch the ignition off and then on again.
– Clear the engine management computer faults.
IMPORTANT
It is not possible to try an injection computer from the Parts Department as it will not be possible to fit it on another
vehicle afterwards.
Note:
C2I (individual injector correction) is a calibration carried out in the factory on each injector to adjust the flow
of each injector precisely.
The correction values are written on a label affixed to each injector, then entered in the computer which can then
actuate each injector by taking account of their manufacturing variation.
13B-52
AFTER REPAIRDeal with any faults displayed by the diagnostic tool. Clear the computer fault memory.
Carry out a road test followed by another check with the diagnostic tool.
V4 MR-372-J84-13B000$061.mif
DIESEL INJECTION
Fault finding – Interpretation of faults13B
DDCR INJECTION
Vdiag No.: 44, 48
DF047
STOREDCOMPUTER SUPPLY VOLTAGE1.DEF: Above maximum threshold.
2.DEF: Below minimum threshold.
NOTESConditions for applying the fault finding procedure to a stored fault:
The fault is present with the engine running above 1000 rpm.
Measure the battery voltage when the ignition is switched on.
If the battery voltage < 10 V recharge the battery.
Check the condition and connection of the battery terminals.
Repair if necessary.
Check the vehicle's charging circuit.
Repair if necessary.
Check the connection and condition of the black 32-track computer connector A.
Repair if necessary.
Check the insulation, continuity and the absence of interference resistance on the following connections:
+ after ignition feed. Track D1 computer connector A
Chassis earth Tracks G4 and H4 computer connector A
Repair if necessary.
DDCR_V44_DF047M/DDCR_V48_DF039P
13B-83V4 MR-372-J84-13B000$070.mif
13B
DDCR INJECTION
Vdiag No.: 44, 48
MAIN STATUSES AND PARAMETERS OF THE COMPUTER:
NOTESOnly check conformity after a full check with the diagnostic tool.
The values shown in this conformity check are given as examples.
Application conditions: Engine off, ignition on.
FunctionParameter or Status
Check or actionDisplay and notes Fault finding
Battery
voltagePR074: Battery
voltage12 V < PR074 < 13.5 VIf there is a fault, apply the
fault finding procedure for the
"Charge circuit".
Engine speedPR055: Engine
speedIndicates the engine's speed of
rotation in rpm.In the event of a fault, apply
the fault finding procedure for
DF005 "Engine speed sensor
circuit".
Accelerator
pedal positionPR030: Accelerator
pedal position.
0%Indicates the position of the
accelerator pedal as a %.
PR030 = 0 %In the event of a fault, apply
the fault finding procedure for
Pedal sensor circuit gang 1
and gang 2
(DF008 and DF009)
and DF113 Sensor supply
voltage.
Coolant
temperaturePR064: Coolant
temperature.
Warm: 90 °CIndicates the coolant
temperature in °C.
Default value: 80°CIn the event of a fault, consult
the interpretation of
parameter PR064 Coolant
temperature.
External air
temperaturePR061: External air
temperatureGives the external air
temperature in °C. This
parameter is controlled by the
UCH and transmitted to the
injection via the multiplex
network.
Default value: 20°C.In the event of a fault, apply
the fault finding procedure for
this fault described in the
UCH document.
DIESEL INJECTION
Fault finding – Conformity check