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
