13B-4V1 MR-376-X76-13B000$010.mif
DIESEL INJECTION
Fault finding – Introduction13B
DCM 1.2 Injection
Program no.: 4C
Vdiag No.: 08
4. FAULT FINDING PROCEDURE
Check the battery charge and
condition of the fuses
Print the system fault finding log
(available on CLIP and in the
Workshop Repair Manual or
Technical Note)
Connect CLIP
See ALP 1
Read the faults
Deal with present faults
Deal with stored faults
Conformity check
Use the fault finding charts (ALPs)
Dialogue with
Computer?
Faults
present
The cause is
still present
The cause is
still presentThe cause is
still present
Contact Techline with the
completed fault finding log
No
NoNo
No No
Ye s
Ye s
Ye sFault
solvedFault
solved Fault
solved
13B-6V1 MR-376-X76-13B000$010.mif
DIESEL INJECTION
Fault finding – Introduction13B
DCM 1.2 Injection
Program no.: 4C
Vdiag No.: 08
5. FAULT FINDING LOG
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.IMPORTANT!IMPORTANT
All faults involving a complex system call for thorough diagnostics with the appropriate tools. The
FAULT FINDING LOG, which should be completed during the fault finding procedure, ensures a
record is kept of the procedure carried out. It is an essential document when consulting the
manufacturer.
IT IS THEREFORE OBLIGATORY TO FILL A FAULT FINDING LOG WHENEVER
THE TECHLINE OR THE WARRANTY RETURNS DEPARTMENT REQUESTS IT.
13B-12V1 MR-376-X76-13B000$030.mif
DIESEL INJECTION
Fault finding – System operation13B
DCM 1.2 Injection
Program no.: 4C
Vdiag No.: 08
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 Unit, electric windows, etc.) active or inactive,
– system faults detected.
Individual injector correction (C2I)
The DCM 1.2 system injectors must be calibrated with correction 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
EEPROM, which can then control the injectors, taking their manufacturing variations into account.
Measuring the angular position (Cylinder reference sensor)
The angular position is measured using a magneto-inductive sensor triggered by machined teeth on the shaft
flywheel. This flywheel has sixty teeth separated by six degrees minus two missing teeth, that form a notch.
A second sensor (Hall effect) triggered by a machined tooth on the high pressure pump drive pulley (synchronised
with the camshaft), which rotates at half the engine speed, supplies an injection cycle running signal. By comparing
the signals from these two sensors, the computer's APS module (Angular Position Subsystem) is able to supply the
synchronisation components to the system assembly, namely:
– the angular position of the flywheel
– the speed and number of the active injector
– the injection cycle progress.
This module also supplies the system with the engine speed signal.
Flow capacity function (VLC)
Because of the combination of several parameters such as the diesel fuel temperature, part wear, clogging of the
diesel filter etc., the system limit may be reached during its service life. If this happens, the rail pressure cannot be
maintained because the pump lacks the necessary capacity. If the pump lacks the necessary capacity, this
programming will therefore reduce the requested flow to a value that will enable the pressure monitoring system to
control the pressure again.
The customer may have noticed a loss of vehicle performance when this program is activated (confirmed by status
Flow capacity function). This is part of normal operation.
13B-13V1 MR-376-X76-13B000$030.mif
DIESEL INJECTION
Fault finding – System operation13B
DCM 1.2 Injection
Program no.: 4C
Vdiag No.: 08
Function: Air flow management
EGR valve control
The EGR system (Exhaust gas recirculation) comprises a proportional EGR valve, with a built-in valve position
feedback potentiometer. The EGR valve position is controlled by the potentiometer in a closed loop and/or by
changes in the estimated air flow.
Special feature of the K9K796 Euro 2 engine (Indonesia): The EGR solenoid valve is present on the vehicle, but not
used. It always remains closed. It must not be replaced on this vehicle (unless there is a mechanical fault).
Calculating the air flow
K9K 790 and 794 engines are not fitted with an air flowmeter. Instead, the amount of fresh inlet air is evaluated
based on the values supplied by the surrounding systems.
The (theoretical) air load is calculated using a model with various calculation parameters, which are:
– the inlet air temperature measured by a sensor located after the turbocharger and/or after the exchanger (if fitted),
– the turbocharging pressure,
– the atmospheric pressure (external air),
– the EGR valve position,
– the fuel flow,
– the engine speed.
The atmospheric pressure sensor is optional. If fitted, it sends back a signal relating to the atmospheric pressure to
an analogue port on the micro-controller. If not, atmospheric pressure is recovered based on the turbocharger
pressure and the engine field.
For K9K 792 and 796 engines, the flow of fresh air entering the engine is measured by a hot-wire ratiometric sensor.
This flowmeter is used to manage the amount of exhaust gas to be recirculated to ensure optimum recirculation
rates. A fresh air temperature sensor is integrated into the flowmeter. Air flow measurement allows closed-loop
control via the EGR valve.
Turbocharger control
K9K 796 engine:
The turbocharging system is made up of a solenoid valve which is used to control the wastegate to adjust the
absolute pressure of the inlet circuit.
K9K 790, 792, 794 engines:
The turbocharger system is controlled by the inlet pressure and does not need to be controlled by the computer.
Pre-postheating actuation
Pre-postheating actuation consists of controlling the heater plugs and the preheating warning light on the instrument
panel. The heater plugs are activated by a preheating unit (controlled by the injection computer), and the power is
supplied by the battery. After the ignition is switched on a preheating delay is activated. The indicator light comes on
for the activation period which is dependent on the battery voltage, atmospheric pressure and coolant temperature.
If 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).
13B-17V1 MR-376-X76-13B000$040.mif
13B
DCM 1.2 Injection
Program no.: 4C
Vdiag No.: 08
COMPUTER REPLACEMENT, PROGRAMMING AND REPROGRAMMING OPERATIONS
The system can be programmed via the diagnostic socket using the diagnostic tool (see Technical Note 3585A
Computer programming and reprogramming procedure and Technical Note 9869A Computer programming
and reprogramming procedure and following the instructions provided by the diagnostic tool).
Before removing the computer in After-Sales, save the computer data using the diagnostic tool by running
command SC003 Save computer data. This command saves the following information:
–C2I parameters (individual injector correction) and engine parameters,
–Measuring system information,
–Injection system reset data. 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).
IMPORTANT
It is not possible to try an injection computer coming from the Parts Department because it will no longer be
possible to use it on another vehicle.
DIESEL INJECTION
Fault finding – Replacement of components
13B-18V1 MR-376-X76-13B000$040.mif
DIESEL INJECTION
Fault finding – Replacement of components13B
DCM 1.2 Injection
Program no.: 4C
Vdiag No.: 08
After the computer has been programmed:
– Switch off the ignition.
– Switch on the ignition again and use the diagnostic tool to carry out the following steps:
– Use command SC001 Write saved data to restore the C2I and the engine adaptive programming.
– Run command VP010 Write VIN.
– Run command AC028 Static test.
– Run command AC154 Low speed fan assembly to test the operation of the 1st speed fan assembly.
– Run command AC153 High speed fan assembly to test the operation of the 2nd speed fan assembly.
– Run command AC250 Heating resistor 1 relay to test the operation of passenger compartment heating resistor 1.
– Run command AC251 Heating resistor 2 relay to test the operation of passenger compartment heating resistor 2.
– Run command AC100 Stop electrical consumer inhibition.
– Run command AC212 Fill new pump chamber.
– Run the starter motor without releasing the key until the engine starts (the pump reprime time until the engine starts
can be up to 20 seconds).
– After the engine has started, refer to ET637 Fill new pump chamber and check that it is Done; if not, repeat the
starting procedure.
–Stop the engine, switch off the ignition (to initialise the computer) and wait 30 seconds.
– After injection system programming, stored faults may appear in other computers.
– If DF1083 Water in diesel fuel warning light circuit appears in the injection computer: on a vehicle fitted with
a water in diesel fuel warning light, perform the fault finding operations described in DF1083 then run command
AC028 Static test; on other vehicles, do not deal with the fault.
– Clear the computer memory RZ001 Fault memory.
IMPORTANT
AFTER A (RE)PROGRAMMING OPERATION, DO NOT DISCONNECT THE BATTERY FOR AT LEAST
30 MINUTES (to carry out other work on the vehicle).
Note:
If commands SC003 Save computer data and SC001 Write saved data have been lost or do not work, after
programming the computer, enter the C2I for each injector manually by reading the C2I on each injector (see
Replacing the injectors).
13B-28
AFTER REPAIRDeal with any faults declared by the diagnostic tool.
Clear the computer memory.
Carry out a road test followed by another check with the diagnostic tool.
V1 MR-376-X76-13B000$071.mif
DIESEL INJECTION
Fault finding – Interpretation of faults13B
DCM 1.2 Injection
Program no.: 4C
Vdiag No.: 08
DF003
PRESENT
OR
STOREDATMOSPHERIC PRESSURE SENSOR CIRCUIT
CO.0: Open circuit or short circuit to earth
CC.1: Short circuit to +12 V
NOTESSpecial notes:
The atmospheric pressure sensor is built into the injection computer.
Use the Wiring Diagrams Technical Note for Logan, Sandero, Duster, Thalia 2/
Symbol 2 or Kangoo VLL.
Look for any wiring harness damage and check the condition and connection of the injection computer connectors,
component code 120.
Check the connection and condition of the injection locking relay connector.
If the connectors are faulty and if there is a repair procedure (see Technical Note 6015A (Renault) or Technical
Note 9804A (Dacia), Electrical wiring repair, Wiring: Precautions for repair), repair the connector, otherwise
replace the wiring.
Move the wiring harness between the injection computer and the battery, component code 107 to see if a change
of status occurs (Present Stored).
Look for any damage to the wiring and check the connection and condition of the battery and its connections.
If the connector is faulty and there is a repair procedure (see Technical Note 6015A (Renault) or Technical Note
9804A (Dacia), Electrical wiring repair, Wiring: Precautions for repair), repair the connector, otherwise replace
the wiring.
Measure the battery voltage when the ignition is switched on.
If the battery voltage is less than 11 V, recharge the battery (see Technical Note 6014A (Renault) or Technical
Note 9859A (Dacia), Checking the charging circuit).
Check the condition and connection of the battery terminals and posts.
DCM1.2_V08_DF003
13B-69
AFTER
REPAIRDeal with any faults declared by the diagnostic tool.
Clear the computer memory.
Carry out a road test followed by another check with the diagnostic tool.
V1 MR-376-X76-13B000$072.mif
DIESEL INJECTION
Fault finding – Interpretation of faults13B
DCM 1.2 Injection
Program no.: 4C
Vdiag No.: 08
DF047
PRESENT
OR
STOREDCOMPUTER SUPPLY VOLTAGE
1.DEF: Above maximum threshold
2.DEF: Below minimum threshold
NOTESConditions for applying the fault finding procedure to a stored fault:
The fault is declared present with the engine running at over 1000 rpm.
Special notes:
Use the Wiring Diagrams Technical Note for Logan, Sandero, Duster, Thalia 2/
Symbol 2 or Kangoo VLL.
Move the wiring harness between the injection computer, component code 120 and the battery, component code
107 to see if a change of status occurs (Present
Stored).
Look for any damage to the wiring harness and check the connection and condition of the battery and its
connections.
If the connectors are faulty and if there is a repair procedure (see Technical Note 6015A (Renault) or Technical
Note 9804A (Dacia), Electrical wiring repair, Wiring: Precautions for repair), repair the connector, otherwise
replace the wiring.
Measure the battery voltage when the ignition is switched on.
If the battery voltage is less than 11 V, recharge the battery.
Check the condition and connection of the battery terminals and posts.
Check the charging circuit of the vehicle (see Technical Note 6014A (Renault) or Technical Note 9859A (Dacia),
Checking the charging circuit).
DCM1.2_V08_DF047