2010 RENAULT SCENIC air condition

13B-3V10 MR-372-J84-13B100$010.mif
DIESEL INJECTION
Fault finding – Introduction13B
DCM 1.2 Injection
Program No.: 4D
Vdiag No.: 48, 4C, 50,
54, 58, 5C
To cut off + after ignition feed, proceed as follows:
Faults
Faults are declared present or stored (depending on whether they appeared in a certain context and have
disappeared since, or whether they remain present but are not diagnosed within the current context).
The present or stored status of faults should be taken into consideration when using the diagnostic tool after
switching on the + after ignition feed (without any system components being active).
For a present fault, apply the procedure described in the Interpretation of faults section.
For a stored fault, note the faults displayed and apply the Notes section.
If the fault is confirmed when the instructions are applied, the fault is present. Deal with the fault.
If the fault is not confirmed, check:
–the electrical connections that correspond to the fault,
–the connectors for this connection,
–the resistance of the component detected as defective,
–the condition of the wires.
Refer to paragraphs 4.1 Checking wiring and 4.2 Checking connectors
Conformity check
The aim of the conformity check is to check data that does not produce a fault on the diagnostic tool because
the data is inconsistent. Therefore, this stage is used to:
–carry out fault finding on faults that do not have a fault display, and which may correspond to a customer complaint.
–check that the system is operating correctly and that there is no risk of a fault recurring after repairs.
This section gives the fault finding procedures for statuses and parameters and the conditions for checking them.
If a status is not behaving normally or a parameter is outside the permitted tolerance values, consult
the corresponding fault finding page.
Customer complaints - Fault finding chart
If the test with the diagnostic tool is OK but the customer complaint is still present, the fault should be processed by
customer complaints. Note:
the left and right-hand xenon bulb computers are powered when the dipped headlights are lit.
Therefore fault finding can only be carried out on them after the ignition has been switched on in fault finding mode
(forced + after ignition feed) and the dipped headlights have been switched on.
For vehicles with a radio frequency remote control - key, use the key to switch off the ignition.
For vehicles with a Renault card,
press the Start button twice briefly (less than 3 seconds),
check that the forced + after ignition feed has been cut off by checking that the computer warning lights on
the instrument panel have extinguished.
A synopsis of the general procedure to follow is provided on the following page in the form of a flow chart.

13B-6V10 MR-372-J84-13B100$010.mif
DIESEL INJECTION
Fault finding – Introduction13B
DCM 1.2 Injection
Program No.: 4D
Vdiag No.: 48, 4C, 50,
54, 58, 5C
4.2 Connector check
1. Visual inspection of the connection:
–Check that the connector is connected correctly and that the male and female parts of the connection are
correctly coupled.
2. Visual inspection of the area around the connection:
–Check the condition of the mounting (pin, strap, adhesive tape, etc.) if the connectors are attached to
the vehicle.
–Check that there is no damage to the wiring trim (sheath, foam, adhesive tape, etc.) near the wiring.
–Check that there is no damage to the electrical wires at the connector outputs, in particular on the insulating
material (wear, cuts, burns, etc.).
Disconnect the connector to continue the checks.
3. Visual inspection of the plastic casing:
–Check that there is no mechanical damage (casing crushed, split, broken, etc.), in particular to the fragile
components (lever, lock, sockets, etc.).
–Check that there is no heat damage (casing melted, darker, deformed, etc.).
–Check that there are no stains (grease, mud, liquid, etc.).
4. Visual inspection of the metal contacts:
(The female contact is called CLIP. The male contact is called TAB.)
–Check that there are no bent contacts (the contact is not inserted correctly and can come out of the back of
the connector). The spring contact of the connector when the wire is pulled slightly.
–Check that there is no damage (folded tabs, clips open too wide, blackened or melted contact, etc.).
–Check that there is no oxidation on the metal contacts.
5. Visual inspection of the sealing:
(Only for watertight connectors)
–Check for the seal on the connection (between the 2 parts of the connection).
–Check the seal at the back of the connectors:
–For unit seals (1 for each wire), check that the unit seals are present on each electrical wire and that they are
correctly positioned in the opening (level with the housing). Check that plugs are present on openings which
are not used.
–For a grommet seal (one seal which covers the entire internal surface of the connector), check that the seal is
present.
–For gel seals, check for gel in all of the sockets without removing the excess or any protruding sections (it does
not matter if there is gel on the contacts).
–For hotmelt sealing (heat-shrink sheath with glue), check that the sheath has contracted correctly on the rear
of the connectors and the electrical wires, and that the hardened glue comes out of the side of the wire.
–Check that there is no damage to any of the seals (cuts, burns, significant deformation, etc.).
If a fault is detected, consult Technical Note 6015A, Repairing electrical wiring. Note:
Carry out each requested check visually. Do not remove a connector if it is not required.
Note:
Repeated connections and disconnections alter the functionality of the connectors and increase the risk of poor
electrical contact. Limit the number of connections/disconnections as much as possible.
Note:
The check is carried out on the 2 parts of the connection. There may be 2 types of connections:
–Connector/Connector.
–Connector/Device.

13B-8V10 MR-372-J84-13B100$020.mif
13B
DCM 1.2 Injection
Program No.: 4D
Vdiag No.: 48, 4C, 50,
54, 58, 5C
I. HAZARDS ASSOCIATED WITH 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,
–components losing seal integrity.
All After-Sales operations must be performed under very clean conditions. This means that no impurities
(particles a few microns in size) should have entered 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,
from brushes,
from paper,
from clothing,
from cloths.
–foreign bodies such as hair,
–ambient air
–etc.
II. ADVICE TO BE FOLLOWED BEFORE ANY OPERATION
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 also 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 single-use only. Once used, they must be thrown out.
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. Each cloth should only be used once.
Use fresh cleaning agent for each operation (used cleaning agent is contaminated). Pour it into an uncontaminated
container.
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.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.
IMPORTANT
Before any work is carried out 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.
DIESEL INJECTION
Fault finding – Cleanliness guidelines

13B-11V10 MR-372-J84-13B100$030.mif
DIESEL INJECTION
Fault finding – List and location of components13B
DCM 1.2 Injection
Program No.: 4D
Vdiag No.: 48, 4C, 50,
54, 58, 5C
Refrigerant pressure sensor:
This sensor is located on the coolant circuit.
Engine coolant temperature sensor:
This sensor is located on the cylinder head near the engine water chamber.
Accelerometer:
This sensor is located on the cylinder block.
Passenger compartment heating resistor relay:
These relays are located in the engine compartment relay unit.
Air conditioning compressor relays:
These relays are located in the engine compartment relay unit.
Fan unit relay:
These relays are located in the engine compartment relay unit.

13B-14V10 MR-372-J84-13B100$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-17V10 MR-372-J84-13B100$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-21V10 MR-372-J84-13B100$050.mif
13B
DCM 1.2 Injection
Program No.: 4D
Vdiag No.: 48, 4C, 50,
54, 58, 5C
High and low pressure pump:
The pump draws in fuel from the tank, which passes through a fuel filter and supplies the fuel injectors.
Injector rail:
The injector rail receives and redistributes fuel under high pressure to the injectors.
Solenoid injectors:
These injectors enable rapid, precise metering of the quantity of fuel injected, with excellent injection process
repetitiveness.
Catalytic converter:
Its role is to convert pollutant gases into harmless gases.
Heater plugs:
The heater plugs create a hot point in the combustion chamber to improve starting in low temperature conditions.
They are also used to improve idle speed stability under some conditions.
Turbocharger:
The turbocharger is used to supply the engine with more air.
Turbocharger control solenoid valve (K9K 724, 766, 802, and 812 only):
This solenoid valve controls the turbocharger wastegate.
Air flowmeter (if present on the vehicle):
The flowmeter measures the amount of fresh air which goes back into the engine.
EGR valve:
The exhaust gas recirculation enables nitrogen oxide (NOx) emissions to be reduced significantly.
Cruise control - speed limiter on - off switch:
This switch turns the cruise control/speed limiter on or off.
Accelerator pedal potentiometer:
The accelerator potentiometer informs the computer about the position of the accelerator pedal (engine load).
Clutch pedal switch:
The clutch pedal switch informs the computer about the pedal status.
TDC sensor:
The angular position is measured using a magneto-inductive sensor triggered by machined teeth on the flywheel.
This sensor gives the engine speed as well as the position of the crankshaft for injection.
Camshaft sensor:
This sensor gives a signal to perform the injection cycle.
When the piston of cylinder 1 is at top dead centre (TDC), it can be either at the end of the compression stroke
or at the end of the exhaust stroke. The camshaft sensor enables a distinction to be made between these two states.
Refrigerant pressure sensor:
Its role is to measure the refrigerant pressure in the air conditioning circuit.
Engine coolant temperature sensor:
The engine coolant temperature sensor informs the computer about the engine coolant temperature.
Water in diesel fuel sensor (New Twingo and Kangoo 2 only):
This sensor determines if there is water present in the diesel fuel.
DIESEL INJECTION
Fault finding – Role of components

13B-22V10 MR-372-J84-13B100$050.mif
DIESEL INJECTION
Fault finding – Role of components13B
DCM 1.2 Injection
Program No.: 4D
Vdiag No.: 48, 4C, 50,
54, 58, 5C
Air temperature sensor:
The air temperature sensor informs the computer about the temperature of air used by the engine. It will calculate
the fresh air flow if the flow sensor is not fitted to the vehicle.
Atmospheric pressure sensor:
This sensor allows the atmospheric pressure to be supplied to the computer.
Inlet manifold pressure sensor:
This sensor indicates the pressure in the inlet circuit.
Rail pressure sensor:
This sensor is fitted to the rail and shows the pressure inside the rail.
Fuel temperature sensor:
This sensor measures the fuel return temperature from the pump and injector return.
Accelerometer:
This sensor measures vibrations and allows injector deviation compensation terms to be calculated.
Passenger compartment heating resistor relay:
This relay allows the passenger compartment heating resistors to be controlled during their activation.
Air conditioning compressor relays:
This relay allows the air conditioning compressor clutch to be controlled during its activation.
Fan unit relay:
This relay actuates the motor-driven fan assemblies when a temperature threshold has been exceeded.