2009 RENAULT TWINGO coolant level

13B-12V6 MR-413-X44-13B000$040.mif
13B
DCM 1.2 Injection
Program No.: 4D
Vdiag No.: 48, 4C, 50,
54, 58, 5C
System outline
The DCM1.2 injection system used on the K9K 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 takes place
when a current pulse is applied to the injector holders. The amount injected is proportional to the rail pressure
and the applied pulse length, and the start of injection is synchronised with the start of the pulse.
The system includes two subsystems, which have different fuel pressure levels:
–The low pressure circuit contains the tank, the diesel fuel filter, the transfer pump and the injector holder
return pipes,
–the high-pressure system includes the high-pressure pump, rail, injector holders and high-pressure pipes.
Finally, there are a certain number of sensors and regulating actuators for controlling and monitoring the entire
system.
Functions performed:
Function: Fuel supply management (timing, flow and pressure).
Quantity of fuel injected and injection timing setting
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 sensor (Crankshaft + Cam lobe for synchronisation),
–accelerator pedal sensor,
–coolant temperature sensor,
–rail pressure sensor,
–atmospheric pressure sensor,
–accelerometer,
–inlet manifold pressure sensor.
Specific vehicle / engine suffix details:
Modus
K9K 750 752 (Euro 3)Inlet manifold temperature and pressure sensor (a sensor which has two functions),
management by the turbocharger control solenoid valve inlet pressure.
K9K 766 (Euro 4)Either a flow sensor with an integrated temperature sensor or a temperature sensor
instead of a flow sensor with inlet manifold temperature sensor, inlet manifold pressure
sensor, management by turbocharger control solenoid valve programming.
K9K 768 (Euro 4)Flow sensor with integrated temperature sensor, inlet manifold pressure sensor,
management by the turbocharger control solenoid valve inlet pressure.
DIESEL INJECTION
Fault finding – Function

13B-14V6 MR-413-X44-13B000$040.mif
DIESEL INJECTION
Fault finding – Function13B
DCM 1.2 Injection
Program No.: 4D
Vdiag No.: 48, 4C, 50,
54, 58, 5C
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 emission control requirements, the droplet size must be reduced and therefore the injection holes
must be smaller.
With smaller holes, less fuel will be able to be introduced at a given pressure, which limits the power. To offset this
disadvantage, the quantity of fuel injected must be increased, which means increased pressure (and more holes in
the injector nozzles). In the Delphi Common Rail injection system, the pressure in the rail can reach 1600 bar
and must be constantly controlled. The measuring circuit comprises an active pressure sensor on the rail connected
to an analogue port on the computer.
The High Pressure pump is supplied at low pressure (5 bar) 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
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 (fuel passes 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 on the pump.
IMV*: Filling actuator.
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 ratio engaged,
–battery charge,
–electrical consumers (Additional heating, Air conditioning, Fan assembly, heated windscreen, etc.) active
or inactive,
–system faults detected.
Individual injector correction (C2I)
The DCM1.2 system injectors must be calibrated with corrective values so that their flow may be adjusted 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 entered into the computer
memory, which can control the injectors, taking their manufacturing variations into account.

13B-17V6 MR-413-X44-13B000$040.mif
DIESEL INJECTION
Fault finding – Function13B
DCM 1.2 Injection
Program No.: 4D
Vdiag No.: 48, 4C, 50,
54, 58, 5C
Function: Hosted functions
Air conditioning management assistance
On models with air conditioning, the DCM1.2 system allows the air conditioning to be deactivated under certain
operating conditions:
–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. high acceleration demand for overtaking, anti-stalling and moving off). These
conditions are only taken into account if they do not occur repeatedly, so as to prevent system instabilities
(erratic deactivation),
–when certain faults appear.
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:
–managing demand for cold air according to the passenger compartment commands and the pressure value,
–determining the power absorbed by the compressor from the pressure,
–determining the fan unit commands according to vehicle speed and pressure.
The driver requests the instrument panel to switch on the air conditioning. The signal is sent to the injection computer
via the multiplex line network. 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.
Thermal regulation of the passenger compartment heating circuit
In a direct injection engine, fuel is injected directly into the combustion chamber. This leads to heat being lost
through the upper part of the engine and consequently, the cylinder head cooling system is smaller in size.
The effect of this is that the temperature of the coolant which flows through this circuit rises more slowly. This coolant
is also used by the passenger compartment heating system. In very cold conditions, it is therefore difficult to achieve
a comfortable passenger compartment temperature quickly.
To reduce the time taken to produce heat, air heating elements, called passenger compartment heating resistors,
are fitted in the passenger compartment heating circuit. The UCH decides whether or not to switch on the passenger
compartment heating resistors, and the UPC or the injection physically controls the heating elements. The injection
computer determines whether to reduce the power supplied to the passenger compartment heating resistors
according to the alternator load and also whether to inhibit the operation of the passenger compartment heating
resistors according to the engine speed, the load, and the vehicle speed.Note:
Fan unit actuation requests can be sent by the injection computer, but these are sent via the multiplex line. These
requests depend on the air conditioning, but also on the engine coolant temperature and vehicle speed.

13B-19V6 MR-413-X44-13B000$040.mif
DIESEL INJECTION
Fault finding – Function13B
DCM 1.2 Injection
Program No.: 4D
Vdiag No.: 48, 4C, 50,
54, 58, 5C
Instrument panel display
The computer manages the data display on the instrument panel relating to engine operation. This covers five
functions: the OBD warning light for European On Board Diagnostics (EOBD), pre-postheating, coolant temperature,
and Level 1 (non critical fault) and Level 2 (emergency stop) engine faults. These five functions are represented by
five warning lights or messages displayed by the trip computer.
Pre-postheating warning light
This warning light indicates that preheating is active.
Engine coolant temperature warning light
This warning light is used as an engine overheating indicator.
–In the event of overheating, it is up to the driver whether to stop the vehicle or continue driving.
OBD warning light
The OBD fault warning light is used to warn the driver of the presence of injection faults producing excessive
pollution or that the EOBD system is deactivated.
The injection computer requests illumination of the OBD warning light for a present fault only after three consecutive
driving cycles.
The visual check of the warning light when the power is switched on (automatic test procedure managed by
the instrument panel) is carried out by the injection computer. It lasts 3 seconds or until the engine starts for
the New Twingo and Kangoo 2.
If a confirmed OBD fault causes the OBD warning light to come on, there should be no flashing after the warning
light illumination test. The instrument panel will also display the message: Check emission control.
The gearbox computer, if fitted, may also request the illumination of this warning light.
Level 1 warning
If there is a minor fault, the computer may request a level 1 warning to be displayed. Usually, the instrument panel
switches on the SERVICE warning light and sends out a "Check the injection" message. Refer to the operation of the
instrument panel (see 83A, instrument panel). Note:
This warning light comes on only if the vehicle is EOBD approved.
Note:
The SERVICE warning light will come on if the instrument panel is configured as cruise control - speed
limiter present, but the function has not yet been detected by the injection computer.

13B-237V6 MR-413-X44-13B000$210.mif
DIESEL INJECTION
Fault finding – Fault finding charts13B
DCM 1.2 Injection
Program No.: 4D
Vdiag No.: 48, 4C, 50,
54, 58, 5C
ALP2 The engine will not start
NOTESOnly consult this customer complaint after a complete check with the diagnostic tool.
Check that the fuel tank is correctly filled and that the fuel is correct: run TEST 13 Diesel fuel conformity check.
Check the levels of engine oil and coolant.
Check the air inlet circuit: run TEST 5 Air inlet circuit check.

Is the catalytic converter clogged or damaged?Replace the catalytic converter (see MR
364 (Mégane II), MR 370 (Scénic II),
MR 385 (Modus), MR 392 (Clio III), MR
411 (New Twingo), MR 417 (Kangoo 2),
Mechanical, 19B, Exhaust, Catalytic
converter: Removal - Refitting).
Check the electrical circuit: run TEST 2 Electrical circuit check.
Check the electrical conformity of the heater plugs (the resistance value of the heater plug must be less
than 2 Ω).

Is the timing set correctly? Carry out the necessary repairs.
Visually check the condition of the engine wiring harness.
YES
NO
NO
YES
A
DCM1.2_V48_ALP2/DCM1.2_V4C_ALP2/DCM1.2_V50_ALP2/DCM1.2_V54_ALP2/DCM1.2_V58_ALP2/DCM1.2_V5C_ALP2

13B-240V6 MR-413-X44-13B000$210.mif
DIESEL INJECTION
Fault finding – Fault finding charts13B
DCM 1.2 Injection
Program No.: 4D
Vdiag No.: 48, 4C, 50,
54, 58, 5C
ALP3 The engine starts with difficulty, or starts then stalls
NOTESOnly consult this customer complaint after a complete check with the diagnostic tool.
Check that the fuel tank is correctly filled and that the fuel is correct: run TEST 13 Diesel fuel conformity check.
Check the levels of engine oil and coolant.
Check the air inlet circuit: run test 5 Air inlet circuit check.
Is the catalytic converter clogged or damaged?Replace the catalytic converter (see MR 364
(Mégane II), MR 370 (Scénic II), MR 385
(Modus), MR 392 (Clio III), MR 411
(New Twingo), MR 417 (Kangoo 2),
Mechanical, 19B, Exhaust, Catalytic
converter: Removal - Refitting).
Check the electrical conformity of the heater plugs (the resistance value of the heater plug must be less
than 2 Ω).
Is the timing set correctly? Carry out the necessary repairs.
Is the compression in order? Carry out the necessary repairs.
Visually check the condition of the engine wiring harness.
YES
NO
NO
YES
NO
YES
A
DCM1.2_V48_ALP3/DCM1.2_V4C_ALP3/DCM1.2_V50_ALP3/DCM1.2_V54_ALP3/DCM1.2_V58_ALP3/DCM1.2_V5C_ALP3

13B-249V6 MR-413-X44-13B000$210.mif
DIESEL INJECTION
Fault finding – Fault finding charts13B
DCM 1.2 Injection
Program No.: 4D
Vdiag No.: 48, 4C, 50,
54, 58, 5C
ALP9 Engine cut-out (stalling)
NOTESOnly consult this customer complaint after a full check with the diagnostic tool.
Check that the fuel tank is correctly filled and that the fuel is correct: run TEST 13 Diesel fuel conformity check.
Check the levels of engine oil and coolant.
Check that the engine has not sucked up its oil (engine racing).
Check the air inlet circuit: run TEST 5 Air inlet circuit check.
Is the catalytic converter clogged or
damaged?Replace the catalytic converter (see MR 364
(Mégane II), MR 370 (Scénic II), MR 385 (Modus),
MR 392 (Clio III), MR 411 (New Twingo), MR 417
(Kangoo 2), Mechanical, 19B, Exhaust, Catalytic
converter: Removal - Refitting).
Visually check the condition of the engine wiring harness.
Check the electrical circuit: run TEST 2 Electrical circuit check.
Check the low pressure circuit: run TEST 1 Low pressure circuit check.
Visually check that there are no leaks on the high pressure circuit: run TEST 7 High pressure circuit
sealing check.
YES
NO
A
DCM1.2_V48_ALP9/DCM1.2_V4C_ALP9/DCM1.2_V50_ALP9/DCM1.2_V54_ALP9/DCM1.2_V58_ALP9/DCM1.2_V5C_ALP9

13B-259V6 MR-413-X44-13B000$210.mif
DIESEL INJECTION
Fault finding – Fault finding charts13B
DCM 1.2 Injection
Program No.: 4D
Vdiag No.: 48, 4C, 50,
54, 58, 5C
ALP13 Excessive consumption
NOTESOnly consult this customer complaint after a full check with the diagnostic tool.
Check that the fuel tank is correctly filled and that the fuel is correct: run TEST 13 Diesel fuel conformity check.
Check the levels of engine oil and coolant.
Is the fuel temperature sensor leaking? Replace the fuel temperature
sensor, (see MR 364 (Mégane II),
MR 370 (Scénic II), MR 385
(Modus), MR 392 (Clio III), MR 411
(New Twingo), MR 417 (Kangoo 2),
Mechanical, 13B, Diesel injection,
Rail pressure sensor: Removal -
Refitting).
Check the low pressure circuit: run TEST 1 Low pressure circuit check.
Visually check that there are no leaks on the high pressure circuit: run TEST 7 High pressure circuit
sealing check.
Check the air inlet circuit: run TEST 5 Air inlet circuit check.
Using the diagnostic tool, check that the injector codes (C2I) are correctly entered on the identification screen. If
not, configure the correct injector codes using command SC002 Enter injector codes.
YES
NO
A
DCM1.2_V48_ALP13/DCM1.2_V4C_ALP13/DCM1.2_V50_ALP13/DCM1.2_V54_ALP13/DCM1.2_V58_ALP13/DCM1.2_V5C_ALP13