FAULT FINDING INTRODUCTION
General method
01E
01E-7
3 - Fault finding innovations:
Development of the electronic and functional design of the Mégane has necessitated changes in the fault finding
processing used. The main fault finding changes are as follows:
●Vehicle to fault-finding tool connection sensor: this equipment is required for communication with the
computers attached to the vehicle's main communications network: the multiplex network. It also enables
communication with the computers diagnosed with the K / L lines.
●New fault-finding tool navigation interface:
The navigation interface of the fault-finding tool has changed to accommodate the Scénic II. Note in particular
the following changes:
–Vehicle identification by entering the VIN:
This can be done manually, or automatically by querying the
vehicle. It also gives the After-Sales type, and the engine and gearbox type.
–Distinction between the fault finding and repair menus:
The fault finding menu incorporates all the
functionalities associated with analysis of an electrical or electronic fault (processing of faults, conformity
checking, actuator commands and processing by customer complaint) whereas the repair menu allows
performance of all the operations associated with replacement of a component and/or modification of the
diagnostic system configuration (configuration read operations, configuration, programming, specific
commands etc.).
●New electronic layout integrity test: As correct operation of the vehicle is dependent on the integrity of the
multiplex network (main functional communication network) and of the cabled electronic systems, the multiplex
network test has changed, becoming the vehicle electronic layout integrity test. The changes are as follows:
–Multiplex network test:
This test remains similar to that already used for RENAULT multiplex vehicles. But it
also incorporates a read of the number of faults from the multiplex computers, physical measurements of the
types of multiplex network faults (open circuit, short circuit to earth, short circuit to the +ve of the faulty rings)
and an assisted help procedure for detecting the defective computer or ring (in the event of total paralysis of
the network). IMPORTANT:
The airbag harness tests and the various physical measurement tests must always be carried out using the
existing diagnostic tool leads and modules.
IMPORTANT:
Entering the VIN, which associated with entering the repair order, can generate the Computer
Diagnostic Sheet electronically.
FAULT FINDING INTRODUCTION
General method
01E
01E-8
–Testing other computers that support fault finding: this test consists of connection and identification of
the computers present on the vehicle which can support fault finding K / L lines.
●New fault finding topics: the fault finding topics are now split into two separate menus:
–Computer diagnosis:
similar to the existing fault finding topics apart from the changed menu presentation.
The states and parameters menus have been modified to allow simultaneous display of these data items
and divided into screens by function and sub-function (example: "ignition" sub-function in Injection).
In addition, the computer fault finding procedure allows access to the vehicle "repair" menu when replacing
parts to be matched with the vehicle (configuration, programming).
–Fault finding by function:
limited to computer fault finding present on the multiplex network of the vehicle
and to the keyless vehicle, air conditioning and tyre functions. This new type of fault finding allows an
overall diagnosis of a function to be made by simultaneous dialogue with all the computers involved in
providing the service. In this way, it is possible to simultaneously analyse all the components associated with
a function and also simultaneously supervise intersystem exchanges between the computers responsible
for a customer service.
Note:
In the event of detecting a faulty component, it is necessary to switch to computer fault finding mode to
perform the configuration operations - programming the replaced part.
If a function fault is detected, a physical part is replaced: hence the choices made concerning
navigation of the diagnostic tool.
