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DIESEL INJECTION
Fault finding – Test13B
13B -265V3 MR-372-J84-13B250$900.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
TEST9
CONTINUED
High pressure circuit check
Note:
According to the vehicle type, maximum visual access will either
be from above or from below.
Visually inspect the condition of the following components:
–outlet pipe of the compressor to the turbocharging air cooler,
–turbocharging air cooler outlet pipe at inlet manifold,
–inlet manifold,
–temperature and pressure sensors.
Is one of these components incorrect (disconnected, cut,
bent, pierced or kinked pipes)?YESReplace
the defective parts
(see MR 364
(Mégane II) or 370
(Scénic II),
Mechanical, 12B,
Turbocharging).
NO
Exhaust system check
Visually inspect the condition of the following engine parts:
–the exhaust manifold circuit to the turbocharger turbine,
–the turbine outlet pipe to the end of the exhaust pipe,
–the inlet manifold to the EGR valve
–check that the temperature and pressure sensors are
connected.
Do some of these components have black or white marks on
them? YES
NO
Run test 5 Turbocharger control solenoid valve check.
Page 266 of 273

DIESEL INJECTION
Fault finding – Test13B
13B -266V3 MR-372-J84-13B250$900.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
TEST10 Diesel fuel conformity check
WARNING
During t hisop eration, it is essential t o:
–refrain from smoking or bringing incandescent objects close to the work area,
–protect yourself against fuel splashes due to residual pressure in the pipes,
–wear safety goggles with side guards,
–wear leaktight gloves (Nitrile type).
IMPORTA NT
–To avoid any corrosion or damage, protect the areas on which fuel is likely to run.
–To prevent impurities from entering the circuit, place protective plugs on all fuel circuit components
exposed to the open air.
Preparations:
Weigh an empty 1300 ml plastic cup (part no. 77 11 171 413) with its cover (part no. 77 11 171 416) using
electronic scales such as those used in body paint workshops (example: PANDA part no. 77 11 224 995). Record
the weight of the empty plastic cup.
This type of plastic cup is used to prepare paint.
Remove 1 litre of fuel at the diesel filter outlet (see MR 364 (Mégane II) or MR 370 (Scénic II), Mechanical,
19C, Tank, Draining the fuel tank), using a pneumatic transfer pump (part no. 634-200) and place it in the
1300 ml plastic cup.
Cover the plastic cup with its cover and let it settle for approximately 2 minutes.
Is the fuel cloudy or does it
separate into two parts?YESThe diesel fuel contains water and is not compliant.
Drain the fuel circuit, including the tank (see MR 364
(Mégane II) or MR 370 (Scénic II), Mechanical, 19C,
Tank, Draining the fuel tank).
NO
EDC16_V51_TEST10
Page 267 of 273

DIESEL INJECTION
Fault finding – Test13B
13B -267V3 MR-372-J84-13B250$900.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
TEST10
CONTINUED 1
Weigh the diesel fuel and note the fuel weight after subtracting the weight of the empty plastic cup and its cover.
Does the fuel weight fall between the minimum and maximum weights given in the table below?
Calculated weight (g.) Fuel
temperature
(˚C) Min. weight Max. weight
821 846 13
821 846 14
820 845 15
819 844 16
819 844 17
818 843 18
817 842 19
816 841 20
816 841 21
815 840 22
814 839 23
814 839 24
813 838 25
Check the fuel temperature by immersing a thermometer in the plastic cup.
YES NO
End of test. The fuel is not correct.
If the fuel weight is l ess than the minimum value then there is petrol in the diesel fuel.
If the fuel weight is greater than the maximum value then there is oil in the diesel fuel.
Drain the fuel circuit, including the tank (seeMR 364 (Mégane II)orMR 370 (Scénic
II), Mechanical, 19C, Tank, Draining the fuel tank).
Page 268 of 273
DIESEL INJECTION
Fault finding – Test13B
13B -268V3 MR-372-J84-13B250$900.mif
TEST10
CONTINUED 2
Note:
If the weight measured reaches the limit values, the measurement can be performed with a 2230 ml plastic cup
(part no.77 11 171 414) and its cover (part no.77 11 171 417):
–Carry out a quick test drive in order to mix the fuel, then remove 2 l of fuel.
–Perform the test again and check the results by multiplying the limit values by 2.
Contact the Techline if you have doubts or problems with the customer.
EDC16
PROGRAM No.: C1
Vdiag No.: 51
Page 269 of 273

DIESEL INJECTION
Fault finding – Test13B
13B -269V3 MR-372-J84-13B250$900.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
Part 1. Overpressure valve return flow test:
TEST11 Incorrect operation of the overpressure valve
Is the engine working?
–Fit Mot. 1760 as shown in the tool fitting procedure (see part 2).
–Press the Start button (with card).
–Measure the length travelled by the diesel fuel in the pipes of the Mot. 1760.
–Replace the overpressure valve if the diesel length travelled is greater than 10 cm.
–The overpressure valve fuel return pipe must be fitted to the injector rail.
–Start the engine.
–Set the Clip diagnostic tool to parameter reading mode.
–Raise the temperature of the engine.
–Display parameter PR063 Fuel temperature. Increase the diesel temperature to above 50˚C.
–Switch off the engine.
–Fit Mot. 1760 as shown in the tool fitting procedure (see part 2).
–View parameter PR038 Rail pressure.
–Ask another Cotech to monitor the rise in fuel in the container during engine turnover, as the container will fill up
quickly if the overpressure valve is leaking.
–Start the engine.
–Accelerate the engine until the pressure in the rail is 550 bar:
–if the engine speed is less than 3000 rpm, maintain this pressure,
–if the engine speed is greater than 3000 rpm, reduce the engine speed until the rail pressure is 500 bar
and maintain this pressure.
–Maintain these conditions for 1 min.
–Release the accelerator pedal and maintain the idle speed for 10 seconds.
–Switch off the engine.
–Measure the length of diesel contained in the measuring cylinder.
–Replace the injector rail if the quantity of diesel is greater than 5 ml.
–Remove Mot. 1760 as shown in the tool removal procedure (see part 3).
YESNO
EDC16_V51_TEST11
Page 270 of 273
DIESEL INJECTION
Fault finding – Test13B
13B -270V3 MR-372-J84-13B250$900.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
Part 2: Fitting the tool:
Remove the engine undertray.
Disconnect the overpressure valve fuel return pipe according to the following procedure (do not remove the clips):
–press the clip,
–pull vertically on the end piece (1) of the fuel return pipe.
TEST11
CONTINUED 1
IMPORTANT
The end piece is fragile. Be careful not to break it by pulling it too hard. Replace
Page 271 of 273
DIESEL INJECTION
Fault finding – Test13B
13B -271V3 MR-372-J84-13B250$900.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
Fit blanking plugs (B), from the kit (part number 77 01 208 209), on the end pieces of the fuel return pipe. If Mot.
1760 is not fitted immediately on the overpressure valve, place a blanking plug (A) on the overpressure valve fuel
return opening.
Shown above is the pipe (Mot. 1760) with the end piece (2) on the right and the plug (4) on the left.
Remove the clip and the plug from the end piece (2) of the pipe of Mot. 1760, leave the plug (4) in place.
TEST11
CONTINUED 2
Page 272 of 273

DIESEL INJECTION
Fault finding – Test13B
13B -272V3 MR-372-J84-13B250$900.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
Connect the pipe of Mot. 1760 to the rail overpressure valve (without removing the clip on the overpressure valve):
–press down on the clip (1) of the overpressure valve,
–insert the end piece (2) in the overpressure valve fuel return opening.
–do not forget to fit the end piece plug (2) to the overpressure valve fuel return opening using the clip supplied.
Remove the plug (4).
Insert the end of the pipe in the measuring cylinder of Mot. 1760, the measuring cylinder is taken from Mot. 1711.
Measure the return flow (see the procedure in part 1 of this test).
Part 3: Removing the tool:
Disconnect the pipe of Mot. 1760 on the overpressure valve:
–press down on the clip (1) of the overpressure valve,
–pull horizontally on the end piece (2) of the pipe of Mot. 1760 while putting a cloth on the end piece (2) to avoid the
drips.
Lift the end piece (2) vertically so that the fuel contained in the pipes flows into the measuring cylinder of Mot. 1760.
Remove the plug from the fuel return pipe end piece (2).
Connect the complete fuel return pipe to the overpressure valve.
Wipe up any diesel run-off with a cleaning cloth (part number 77 11 211 707).
TEST11
CONTINUED 3
IMPORTANT
Use a cleaning cloth (part number 77 11 211 707) to absorb fuel run-off.