
13B-18V12 MR-372-J84-13B300$030.mif
DIESEL INJECTION
Fault finding – System operation13B
EDC16CP33
Program No.: C4
Vdiag No.: 04, 08, 18, 1C,
20, 24, 26, 28, 34, 38, 44,
4C, 54, 58, 5C, 60, 62, 74
VI - Pre-postheating actuation
Pre/postheating control involves actuating the heater plugs and the preheating indicator light on the instrument
panel (multiplex signal).
The heater plugs are actuated by a static relay.
After the ignition is switched on, a preheating delay is activated. The length of time that the warning light is lit
depends on the coolant temperature, air temperature, atmospheric pressure and battery voltage. When the coolant
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). Postheating can last up
to5 minutes.
IMPORTANT:
There are two types of heater plug: SLOW and FAST:
SLOW plugs are identified by a black ring.
FAST plugs are identified by a white ring.
The heater plugs fitted on the vehicle must be replaced with plugs of the same type; otherwise there is
a risk of the heater plugs deteriorating which could lead to engine destruction.
Only Vdiag 20, 24, 38 and 74:
when replacing heater plugs with plugs which differ from those currently fitted on the vehicle (replacement of
SLOW plugs with FAST plugs), the computer must be configured (see Replacement of components, Replacing
heater plugs) by running command SC036 Reinitialise programming and selecting Heater plugs if this choice
is available, then following the procedure.

13B-59
AFTER REPAIRDeal with any other faults. Clear the fault memory.
Switch off the ignition until the end of the power-latch phase, and carry out a road test
followed by a check with the diagnostic tool.
V12 MR-372-J84-13B300$071.mif
DIESEL INJECTION
Fault finding – Interpretation of faults13B
EDC16CP33
Program No.: C4
Vdiag No.: 04, 08, 18, 1C,
20, 24, 26, 28, 34, 38, 44,
4C, 54, 58, 5C, 60, 62, 74
DF018
PRESENT
OR
STOREDLOW SPEED FAN ASSEMBLY CONTROL CIRCUITCO: Open circuit
CC.1: Short circuit to + 12 V
CC.0: Short circuit to earth
1.DEF: Internal electronic fault
NOTESConditions for applying the fault finding procedure to a stored fault:
If the fault reappears after:
– the ignition is switched on.
– clearing the fault from the memory,
– the relay is actuated using command AC154 Low speed fan assembly.
Special notes:
– the high speed fan assembly is actuated at the same time as the low speed fan
assembly.
–the level 1 warning light is illuminated.
Use bornier Elé. 1681 for all operations on the connector of the engine management
computer.
Use the Wiring Diagram Technical Note, Laguna II ph2, Vel Satis ph2, Espace IV
ph2, Mégane II ph2, Scénic II ph2.
CO
NOTESNo low speed fan assembly control.
Check the condition of the low speed fan assembly relay mounting connector (see Wiring Diagram Technical
Note, Laguna II ph2, Vel Satis ph2, Espace IV ph2, Mégane II ph2, Scénic II ph2, component code 700 or
336).
Check the condition of the engine management computer connector (see Wiring Diagram Technical Note,
Laguna II ph2, Vel Satis ph2, Espace IV ph2, Mégane II ph2, Scénic II ph2, component code 120).
If the connector or connectors are faulty and if there is a repair procedure (see Technical Note 6015A, Repairing
electrical wiring, Wiring: Precautions for repair), repair the connector, otherwise replace the wiring.
EDC16CP33_V18_DF018 / EDC16CP33_V1C_DF018 / EDC16CP33_V54_DF018 / EDC16CP33_V20_DF018 / EDC16CP33_V24_DF018 /
EDC16CP33_V04_DF018 / EDC16CP33_V08_DF018 / EDC16CP33_V44_DF018 / EDC16CP33_V4C_DF018 / EDC16CP33_V34_DF018 /
EDC16CP33_V38_DF018 / EDC16CP33_V74_DF018 / EDC16CP33_V28_DF018 / EDC16CP33_V62_DF018 / EDC16CP33_V26_DF018 /
EDC16CP33_V60_DF018

13B-240
AFTER REPAIRDeal with any other faults. Clear the fault memory.
Switch off the ignition until the end of the power-latch phase, and carry out a road test
followed by a check with the diagnostic tool.
V12 MR-372-J84-13B300$074.mif
DIESEL INJECTION
Fault finding – Interpretation of faults13B
DF895
PRESENT
OR
STOREDPRESSURE REGULATION ON RAIL1.DEF: Below minimum threshold
2.DEF: Above maximum threshold
3.DEF: Negative loop deviation
4.DEF: Positive loop deviation
NOTESConditions for applying the fault finding procedure to a stored fault:
The fault is declared present after:
– the ignition is switched on,
– with the engine running,
– road test.
Priorities when dealing with a number of faults:
– DF898 Pressure regulator circuit on rail,
– DF897 Pressure regulator circuit on pump,
– DF896 Pressure regulation on pump.
Special notes:
DF895 depends on the pressure regulator built into the rail (DRV).
DF896 Pressure regulation on pump depends on the pressure regulator integrated
in the pump (MPROP).
The fuel pressure regulator built into the rail (DRV) and the fuel pressure regulator built
into the pump (MPROP) are never actuated at the same time.
If the fault is present:
– particle filter regeneration is inhibited,
– the engine stops and the level 2 warning light comes on: 1.DEF, 4.DEF,
–the level 1 warning light comes on: 2.DEF, 3.DEF, 4.DEF,
– engine torque limited 2.DEF, 3.DEF, 4.DEF,
– the rail pressure is regulated by a regulator built into the pump (MPROP): 2.DEF,
3.DEF, 4.DEF.
Use bornier Elé.1681 for all operations on the engine management computer.
Use the Wiring Diagram Technical Note, Laguna II ph2, Vel Satis ph2, Espace IV
ph2, Mégane II ph2, Scénic II ph2.
EDC16CP33_V18_DF895 / EDC16CP33_V1C_DF895 / EDC16CP33_V54_DF895 / EDC16CP33_V20_DF895 / EDC16CP33_V58_DF895 /
EDC16CP33_V5C_DF895 / EDC16CP33_V24_DF895 / EDC16CP33_V04_DF895 / EDC16CP33_V08_DF895 / EDC16CP33_V44_DF895 /
EDC16CP33_V4C_DF895 / EDC16CP33_V34_DF895 / EDC16CP33_V38_DF895 / EDC16CP33_V74_DF895 / EDC16CP33_V28_DF895 /
EDC16CP33_V62_DF895 / EDC16CP33_V26_DF895 / EDC16CP33_V60_DF895
EDC16CP33
Program No.: C4
Vdiag No.: 04, 08, 18, 1C,
20, 24, 26, 28, 34, 38, 44,
4C, 54, 58, 5C, 60, 62, 74

13B-473
AFTER REPAIRCarry out a road test, then check with the diagnostic tool.
V12 MR-372-J84-13B300$170.mif
DIESEL INJECTION
Fault finding – Fault Finding Chart13B
ALP2
CONTINUED 1
If the connection or connections are faulty and there is a repair procedure (see Technical Note 6015A, Electrical
wiring repair, Wiring: Precautions for repair), repair the wiring, otherwise replace it.
Check the conformity of the engine earths (oxidation, tightness, etc.).
Check the mounting and condition (overheating) of the sensor.
Check the synchronisation of the camshaft sensors and the engine speed sensors with the display of ET238
Synchronisation. If synchronisation is not active, refer to the checks described in DF195 Camshaft/engine
speed sensor consistency.
Test the high pressure fuel circuit:
Run scenario SC035 High pressure fuel circuit fault finding.
To interpret the result, apply the interpretation of command SC035 (see Interpretation of commands).
Check the fuel circuit sealing: run Test 3 Low pressure circuit check.
If Test 3 is correct.
If Test 3 is not correct, proceed as follows:
Check the conformity of the type of heater plugs configured:
For Vdiag 20, 24, 38 and 74: consult ET781 Heater plugs in the Ignition/Preheating subfunction and check the
conformity with the type of plugs installed:
– Slow plugs have a black ring.
– Fast plugs have a white ring.
If the heater plugs are being replaced with plugs of a different type (see Replacement of components, Replacing
heater plugs).
For all Vdiags, check that all 4 plugs have the same colour ring.
Check that the heater plugs are actuated using the AC037 Preheating relay command.
Check the sealing and condition of the inlet circuit: run Test 4 Turbocharged air inlet circuit check, and follow
the related fault finding procedure (see Test 4).
EDC16CP33
Program No.: C4
Vdiag No.: 04, 08, 18, 1C,
20, 24, 26, 28, 34, 38, 44,
4C, 54, 58, 5C, 60, 62, 74