13B-89
MR-372-J84-13B200$288.mif
V13
DIESEL INJECTION
Fault finding – Interpretation of faults
EDC16
Program No.: C1
Vdiag no.: 18, 1C, 20,
50, 58, 5C
13B
DF055
CONTINUED 1
1.DEF
NOTESNone
Check the turbocharging pressure sensor connections,
Check the connections of the turbocharging solenoid valve,
Check the injection computer connections.
Repair if necessary.
Check the sealing of the high pressure air circuit:
– disconnected or pierced pipes,
– pressure sensor disconnected or poorly fitted (seal present),
– intercooler pierced (to check the intercooler: with the vehicle stopped, stabilise the engine speed between 3500
and 4000 rpm and check that there are no leaks).
Check the conformity of the turbocharging pressure signal and run test 2Air line at the turbocharger, test 6
Turbocharger control solenoid valve check and test 7 Turbocharger.
Check that the turbocharger and the control circuit are working:
– With the engine stopped, check that the control rod is (in the rest position the control rod is retracted).
– start the engine and check that the control rod disengages and pulls on the turbocharger geometry (when the
engine is stopped, the control rod should return to the rest position).
If the control rod does not move correctly, carry out the following checks:
1. Check the control vacuum pressure:
– Disconnect the solenoid valve inlet hose and connect it to a pressure gauge,
– start the engine and stabilise it at idle speed,
– if the vacuum is not between 700 mbar < X < 900 mbar, check the vacuum circuit from the vacuum pump,
– Stop the engine, reconnect the intake hose and proceed to step 2.
2. Solenoid valve control check:
– Disconnect the solenoid valve outlet hoses,
– start the engine and stabilise it at idle speed,
– place your hand on the solenoid valve and block the outlet connection with your thumb,
– if there is no detectable vibration of the solenoid valve, check that the computer output is operating correctly
(see DF054 Turbocharging solenoid valve control circuit 1.DEF).
3. Solenoid valve operation check:
– Connect the pressure gauge to the solenoid valve outlet union,
– start the engine and stabilise it at idle speed,
– if the vacuum is not 700 mbar < X < 900 mbar, replace the solenoid valve.
AFTER REPAIRDeal with any faults.
Carry out a road test followed by another check with the diagnostic tool.
13B-304
MR-372-J84-13B200$756.mif
V13
DIESEL INJECTION
Fault finding – Interpretation of commands
EDC16
Program No: C1
Vdiag No: 18, 1C, 20,
50, 58, 5C
13B
*ocr = opening cyclic ratioAC004
CONTINUED
Turbocharger control circuit check (continued)
4) Check the operation of the turbocharger:
a) Attach a vacuum pump to the hose connected to the turbocharger control diaphragm,
Apply a vacuum of 700 mbar < X < 900 mbar:
If there is a leak, replace the turbocharger (diaphragm included).
b) Check the movement and adjustment of the control rod (see MR 364 (Mégane II), 370 (Scénic II) or 395
(Laguna II), Mechanical, 12B, Turbocharging).
If the control rod is sticking, replace the turbocharger.
c) Engine cold and stopped:
Remove the turbocharger inlet duct and check that the compressor turns freely on the axis.
d) If the fault persists:
Check that the exhaust manifold is not leaking.
Check that the exhaust is not blocked.
Carry out the necessary repairs.
5) Check the computer output stage with the solenoid valve connected:
This operation can only be carried out if the checks indicated in step no. 2 are not conclusive.
→Or using a voltmeter:
Connect the voltmeter earth lead to connection 3FB (Laguna II and Mégane II) or 3FB1 (Scénic II) of
component 1475 and the positive lead to connection 3MG.
Clear any solenoid valve fault then run command AC004:
The voltmeter should display ten cycles of two successive voltages ~ = battery voltage X current OCR*.
Either: ~ 2.5 V (OCR* of 20%) then ~ 8.7 V (OCR* of 70%).
→Or using an oscilloscope (range 5 V/division and time base 1 ms/division):
Connect the oscilloscope earth lead to the battery earth and the positive test pin to connection 3FB (Laguna II
and Mégane II) or 3FB1 (Scénic II) of component 1475.
Clear any solenoid valve faults, then run command AC004:
the oscilloscope should display a square wave signal of 12.5 V in amplitude at a frequency of 140 Hz
(with an OCR* passing from ~ 20 to ~ 70%).
if the measurement is correct, replace the solenoid valve.
if the measurement does not show any control or continuous voltage, contact the techline.
13B-319
MR-372-J84-13B200$828.mif
V13
EDC16
Program No.: C1
Vdiag no.: 18, 1C, 20,
50, 58, 5CDIESEL INJECTION
Fault finding – Fault Finding Chart13B
ALP 2 Starting difficult (or impossible)
NOTESBefore dealing with this customer complaint, check that there are no faults, and
the conformity (or otherwise) of the parameters and statuses using the
diagnostic tool.
If the customer complaint is not eliminated, perform the following checks.
Is it difficult or impossible to start the engine?
PART A:
Check the engine earths.
Ensure that the engine speed reaches 250 rpm with the starter motor, as displayed on the parameter screen (PR055
Engine speed).
If the engine speed is less than 250 rpm, refer to Technical Note 6014A, Checking the charging circuit.
If the engine speed shown on CLIP is zero and the engine is running, check the resistance of the engine speed
sensor between connections 3BG and 3BL of component 149:
Replace the sensor if its resistance is not 510 Ω < X < 850 Ω at 20°C
Check the continuity of the following connections:
– connection codes 3BG and 3BL between components 120 and 149.
Check the conformity of the engine earths (oxidation, tightness, etc.).
Check the mounting, the gap (if necessary refer to the information in the workshop repair manual for the vehicle) and
the condition of the sensor (overheating).
Replace if necessary.
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 consistency.
check the fuel circuit sealing.
If the fault is still present, see DF053 Rail pressure regulation function 2.DEF, step 4.
Check that the heater plugs are actuated using the AC001 Preheating unit command.
Check the sealing and condition of the inlet circuit: run Test 4 Turbocharged air inlet circuit check and follow the
associated fault finding procedure.
Check that there are no foreign bodies on the flowmeter grille: run Test 5 Air flowmeter and follow the associated
fault finding procedure.
Check the position of the exhaust gas recirculation valve.
Check that the exhaust is not blocked: run Test 1 Exhaust pipe check and follow the associated fault finding
procedure.
Check the consistency of the signal from the engine coolant temperature sensor.
Check the operation of the pressure regulator (see AC011 Rail pressure regulator).
Check the operation of the injectors (excessive return leak, clogging, seizing): run Test 9 Poor injector operation.
Check the engine timing (and the position of the high pressure pump sprocket).
Check the balance of the compressions, according to the power consumption during the starting phase
(Compression test menu on the CLIP Technic tool or using a compression gauge)
after the operation, clear the faults caused by disconnecting the regulator and the heater plugs.
End of part AImpossible
AFTER REPAIRCarry out a road test followed by a complete check with the diagnostic tool.
EDC16_V50_ALP2/EDC16_V58_ALP2/EDC16_V5C_ALP2/EDC16_V18_ALP2/EDC16_V1C_ALP2/EDC16_V20_ALP2