CD changer RENAULT SCENIC 2012 J95 / 3.G Engine And Peripherals EDC16CP33 Workshop Manual

Page 16 of 510

13B-16V12 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
III - Management of the damper valve
The damper valve is now responsible for two functions:
– Damping: when the engine is switched off, the flap closes in order to block the passage of air towards the cylinders.
The aim of this is to stop the engine as quickly as possible and to reduce instabilities when the engine is switched
off.
– "Valving" function depending on the engine operation: the damper valve closes by a few % to create a "venturi"
effect at the EGR valve passage section.
The aim of this is to accelerate the air flow of EGR gases and to reduce the emission of pollutants.
IV - Exhaust gas recirculation management
The EGR (Exhaust Gas Recirculation) system involves removing exhaust gases and reintroducing them into the
inlet.
This system plays a major role in reducing diesel engine emissions. The EGR system is cooled by a gas - water
exchanger, as on most Euro IV engines. This cooler has a dual position bypass valve, which allows the gas to be
cooled or not depending on the emission control requirements. The bypass circuit is inside the cooler (not visible
from the outside). The valve control rod is visible from the outside.
The exhaust gases are collected in the exhaust manifold (before the turbocharger), then directed to the EGR cooler
and the EGR valve. The EGR valve connects the air circuit between the damper valve and the inlet manifold; the
EGR valve is positioned next to the damper valve.
The EGR valve is activated every time the engine stops by performing 10opening/closing cycles. This programming
activates the EGR valve in order to prevent it from clogging. The program is no longer active if there are any system
faults.
The EGR system does not operate below 5°C (air flowmeter temperature).
– The controlled EGR cooler bypass
The EGR cooler bypass is controlled by an all-or-nothing solenoid valve, connected on one side to the vacuum
pump, and on the other side to the bypass control diaphragm. It is actuated according to the coolant temperature
and the engine operating status. Gases flow into the EGR section of the cooler unless the engine is cold, in which
case they flow through the bypass valve. There is also a regular actuation function for the bypass valve to prevent it
from clogging.
– EGR valve
The EGR valve is supplied by direct current and connected to a potentiometer copying the position of the valve.
The opening of the valve is actuated (H bridge) by a positive command 0 to 100%.
The valve is controlled using a double regulation loop.
The first loop (fastest) is a position loop. It brings the valve to the desired position by a loop connection using the
signal from the position sensor.
The second loop is slower and is an air flow loop. At a given operating point, the air flow setpoint is attained by
adjusting the quantity of exhaust gas flowing through the EGR valve and the flow of fresh air passing through the
damper valve. At a total constant flow, the more exhaust gas recirculation, the less fresh air there is and vice versa.
The air flow is measured by the flowmeter and the setpoint is attained using both the EGR valve position setpoint
and the damper valve position setpoint.

Page 347 of 510

13B-347
AFTER REPAIRCarry out a road test, then check with the diagnostic tool.
V12 MR-372-J84-13B300$121.mif
DIESEL INJECTION
Fault finding – Interpretation of parameters13B
PR041
CONTINUED
Sensor electrical conformity
Check the continuity and absence of interference resistance of the following connections:
•3LQ between components 120 and 1071,
•3LP between components 120 and 1071,
•3LN between components 120 and 1071.
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.
Vehicle with the ignition on, and the engine stopped for at least 1 minute:
Compare the values of PR041 Turbocharging pressure and PR035 Atmospheric pressure.
If the difference between PR041 and PR035 is greater than 0.1 bar,
check the value of PR035 by comparing it with the reading on a vehicle in the workshop which is correct.
If the value of PR035 is not correct (difference greater than 0.1 bar between the 2 vehicles), contact the Techline.
Otherwise (when the value of PR035 is correct), replace the turbocharger pressure sensor.
If the difference between PR041 and PR035 is less than 0.1 bar.
Start the engine, with the engine idling:
Compare the values of PR041 and PR035.
If the difference between PR041 and PR035 is greater than 0.2 bar.
Check the air inlet circuit:
Apply Test 4 Turbocharged air inlet circuit check.
Low and high pressure air circuit sealed and not obstructed: ducts, mounting clamps present and tightened,
turbocharging pressure sensor fitted, exchanger, etc.
Check that the damper valve is not jammed closed.
Repair if necessary.
EDC16CP33
Program No.: C4
VDiag No.: 04, 08, 18, 1C,
20, 24, 26, 28, 34, 38, 44,
4C, 54, 58, 5C, 60, 62, 74

Page 439 of 510

13B-439V12 MR-372-J84-13B300$150.mif
DIESEL INJECTION
Fault finding – Interpretation of commands13B
AC004TURBOCHARGING SOLENOID VALVE
NOTESPerform this fault finding procedure:
– following interpretation of an unresolved fault or,
– following application of the interpretation of PR041 Turbocharging pressure or
– after a customer complaint (loss of power, smoke etc.).
Use the Wiring Diagram Technical Note, Laguna II ph2, Vel Satis ph2, Espace IV
ph2, Mégane II ph2, Scénic II ph2.
1. The following procedure is for checking that the turbocharger and its control circuit are working
properly.
Preliminary operation
Check the high pressure air circuit is sealed:
Apply Test 4 Turbocharged air inlet circuit check or Test 3 Low pressure circuit check.
Pipe not joined or pierced, pressure sensor disconnected or poorly fitted (seal present), exchanger pierced.
To test the exchanger: stabilise the engine speed between 3500 and 4000 rpm with the vehicle stopped and
check that there are no leaks.
Measure the resistance between connections3FB and 3MG of component1475.
If the resistance is not between 18 Ω and 22 Ω at + 23°C, replace the turbocharging solenoid valve.
Check the continuity of the following connection:
•3MG between the components 120 and 1475.
Check the + 12 V after relay supply of the turbocharging solenoid valve on the following connection:
•3FB of component 1475.
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.
EDC16CP33_V18_AC004 / EDC16CP33_V1C_AC004 / EDC16CP33_V54_AC004 / EDC16CP33_V20_AC004 / EDC16CP33_V58_AC004 /
EDC16CP33_V5C_AC004 / EDC16CP33_V24_AC004 / EDC16CP33_V04_AC004 / EDC16CP33_V08_AC004 / EDC16CP33_V44_AC004 /
EDC16CP33_V4C_AC004 / EDC16CP33_V34_AC004 / EDC16CP33_V38_AC004 / EDC16CP33_V74_AC004 / EDC16CP33_V28_AC004 /
EDC16CP33_V62_AC004 / EDC16CP33_V26_AC004 / EDC16CP33_V60_AC004
EDC16CP33
Program No.: C4
Vdiag No.: 04, 08, 18, 1C,
20, 24, 26, 28, 34, 38, 44,
4C, 54, 58, 5C, 60, 62, 74
AFTER REPAIRCarry out a road test, then check with the diagnostic tool.

Page 500 of 510

13B-500V12 MR-372-J84-13B300$180.mif
DIESEL INJECTION
Fault finding – Test13B
TEST4
CONTINUEDTurbocharged air inlet circuit check
Check that there is no leak at the exhaust manifold, in particular at the exhaust manifold/turbocharger connection.
Check the exhaust, run Test 1 Exhaust pipe check.
Carry out the necessary repairs.
Visually check the EGR circuit sealing.
Note:
The operational clearance of the EGR exchanger flap shaft leaves slight traces of a black substance due to
inconsequential leakage. Do not replace this part.
– Check the condition of the intercooler:
– clogging,
– leaks (vehicle stationary, stabilise the engine speed between 3500 rpm and 4000 rpm and check that there are
no leaks).
Replace if necessary.
Check that the turbocharging pressure sensor take-off point is not blocked.
Carry out the necessary repairs
END OF TEST.
A
EDC16CP33
Program No.: C4
Vdiag No.: 04, 08, 18, 1C,
20, 24, 26, 28, 34, 38, 44,
4C, 54, 58, 5C, 60, 62, 74