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13B-311
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
AC039
HIGH-SPEED FAN ASSEMBLY RELAY
NOTESThere must be no present or stored faults.
Perform this fault finding procedure if a malfunction appears on the command menu
or after an engine cooling system or air conditioning fault.
Refer to the Wiring Diagrams Technical Note for the vehicle to locate the fuses and
relays concerned.
If the high-speed fan assembly relay does not operate when command AC039 is run:
Check the high-speed fan assembly relay mounting and the connections of the engine management computer.
Repair if necessary.
If the fault is still present, check that the relay is actuated by the engine management computer as follows:
Disconnect the high-speed fan assembly relay, fit a 50 Ω < X < 100 Ω resistor on its mounting in place of the
coil, and connect a voltmeter as follows:
Positive terminal to the +12 V battery.
Negative terminal to connection 3JP of the high-speed fan assembly relay mounting.
Clear the fault and run command AC039.
If the voltmeter indicates the battery voltage (three 2-second ON-OFF cycles), replace the relay.
If the voltmeter does not show the battery voltage (three 2 second ON-OFF cycles), contact the techline.
If the high-speed fan assembly relay is supplied by command AC039, but there remains a fault with the
triggering the fan assembly. Check using the wiring diagram:
– the conformity of the fan assembly maxi-fuse.
– + battery feed on connection BP71 of the high-speed fan assembly relay mounting,
– the conformity of the high-speed fan assembly relay,
– the continuity of connection 49B between components 597 and 262,
– the conformity of the fan assembly,
– the continuity of connection MAS of component 262.
Carry out the necessary repairs.
EDC16_V18_AC039/EDC16_V1C_AC039/EDC16_V20_AC039
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13B-312
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
AC063
THERMOPLUNGER NO. 1 RELAY
(check that the computer is correctly configured).
NOTESThere must be no present or stored faults.
Perform this fault finding procedure if there is a fault in the command menu, or a
passenger compartment heating/demisting problem.
Refer to the Wiring diagrams Technical Note for the vehicle to locate the fuses and
relays concerned.
vdiag 50, 58, 5c:
If the additional heater no. 1 relay does not operate when running command AC063:
check the engine management computer connections.
Check the connections of thermoplunger no. 1.
Repair if necessary.
Check for + 12 V after ignition supply on connections BP9 and 3FB of component 1067.
If there is no + 12 V supply, refer to the interpretation of fault DF015 Main relay control circuit.
Repair if necessary.
Check the continuity, absence of interference resistance and insulation on connection 3JA between
components 120 and 597.
If the connection or connections are faulty and there is a repair method (see Technical Note 6015A, Repairing
electrical wiring, Wiring: Precautions for repair), repair the wiring, otherwise replace it.
Using a test light, check the supply by running command AC063 on connection 3JB between components 1067
and 898.
Measure the resistance of thermoplunger no. 1.
Replace thermoplunger no. 1 if the resistance is greater than 2 Ω.
Replace the water heater interface unit if necessary.
Using a test light, check that the water heater interface unit is properly earthed by running command AC063
on connection 3JA between components 120 and 597.
If the fault is still present, contact the techline.
EDC16_V50_AC063/EDC16_V58_AC063/EDC16_V5C_AC063/EDC16_V18_AC063/EDC16_V1C_AC063/EDC16_V20_AC063
Page 314 of 365

13B-314
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
AC064
THERMOPLUNGER NO. 2 RELAY
(check that the computer is correctly configured).
NOTESThere must be no present or stored faults.
Perform this fault finding procedure if there is a fault in the Command menu, or a
passenger compartment heating/demisting problem.
Refer to the Wiring Diagram Technical Notes for the vehicle to locate the fuses and
relays concerned.
vdiag 50, 58, 5c:
If the additional heater no. 2 relay does not operate when running command AC064:
check the engine management computer connections.
Check the connections of thermoplungers 2 and 3.
Repair if necessary.
Check for + 12 V after ignition supply on connections 3FB and BP91 of component 1068.
If there is no + 12 V supply, refer to the interpretation of fault DF015 Main relay control circuit.
Repair if necessary.
Check the continuity, absence of interference resistance and insulation to earth of connection 3JAA
between components 120 and 597.
If the connection or connections are faulty and there is a repair method (see Technical Note 6015A, Repairing
electrical wiring, Wiring: Precautions for repair), repair the wiring, otherwise replace it.
Check for + 12 V after ignition feed between connections BP91 and 3JAD of component 597 and connection
3JAD of components 1072 and 1073.
Measure the resistance of thermoplungers 2 and 3.
Replace thermoplunger no. 2 or 3 if the resistance is greater than 2 Ω.
Replace the water heater interface unit if necessary.
Using a test light, check that the water heater interface unit is properly earthed on connection 3JAA between
components 120 and 597.
if the fault is present, contact the techline.
EDC16_V50_AC064/EDC16_V58_AC064/EDC16_V5C_AC064/EDC16_V18_AC064/EDC16_V1C_AC064/EDC16_V20_AC064
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13B-318
MR-372-J84-13B200$828.mif
V13
13B
DIESEL INJECTION
Fault finding – Fault Finding Chart
ALP 1 No dialogue with engine management computer
Try to establish dialogue with a computer on another vehicle to check that the diagnostic tool is not faulty.
Check the battery voltage and carry out the operations necessary to obtain the correct voltage
(9.5V
If the tool is not at fault, and dialogue cannot be established with any other computer on the same vehicle, the
cause could be a faulty computer interfering on the multiplex network.
disconnect the engine management computer.
try to establish dialogue with another computer.
if the fault is still present, reconnect the computer and proceed by elimination by successively disconnecting all
the following computers (according to wiring diagram and equipment): air conditioning, airbag, abs and esp, uch,
instrument panel, central communication unit, proximity sensor.
try to establish a dialogue between each disconnection:
if, after a disconnection, you manage to establish dialogue, perform the fault finding procedure for the relevant
computer.
Carry out a fault finding procedure on the multiplex network using the diagnostic tool.
Check for the injection fuses on the protection and switching unit and/or in the engine fuse box and check their
condition.
Check the connection of the computer connectors and the condition of its connections.
Check the injection computer earths (quality, oxidation, tightness of earth bolts on the battery terminal).
Check that the supply to the computer is correct:
Earth on connections NT (Laguna II) or N (Scénic II and Mégane II) of component 120.
+ after ignition feed on connection AP29 (Laguna II) or AP15 (Scénic II and Mégane II) of component 120.
Check that the power supply to the diagnostic socket is correct:
– + before ignition feed on connection BP32 (Scénic II and Mégane II) or BCP4 (Laguna II) of component
225.
– + after ignition feed on connection AP43 (Scénic II and Mégane II) or AP10 (Laguna II) of component
225.
– Earth on connections MAN and NAM (Scénic II and Mégane II) or MA and NAP (Laguna II) of component
225.
If dialogue has still not been established after these checks, contact the techline.
AFTER REPAIRCarry out a road test followed by a complete check with the diagnostic tool.
EDC16_V50_ALP1/EDC16_V58_ALP1/EDC16_V5C_ALP1/EDC16_V18_ALP1/EDC16_V1C_ALP1/EDC16_V20_ALP1 EDC16
Program No.: C1
Vdiag no.: 18, 1C, 20,
50, 58, 5C
MR-372-J84-13B200$828.mif