FAULT FINDING INTRODUCTION
General method
01E
01E-2
101EFAULT FINDING INTRODUCTION
General method
The Scénic II is a multiplexed vehicle equipped with a communications network operating at a speed of
500 kBauds.
This change has allowed a new optimisation of the electronic layout of the vehicle in two ways:
●Distribution of vehicle functions: the main computers present on the multiplex network manage several
functions (example: UCH: access - vehicle protection - lighting - wipers - passenger compartment heating - tyre
pressure monitor).
●Elimination of redundant sensors: the "steering wheel angle" signal used by the electronic stability program
is produced by the electric power assisted steering which then transmits it to the multiplex network. So the
steering wheel angle sensor used by the electronic stability program does not exist.
This change has also allowed fault finding on computers present on the multiplex network to be performed by the
main communication network of the vehicle (multiplex network) instead of a cable network dedicated to fault
finding (K / L lines).Warning:
Scénic II diagnostics can only be done with the CLIP fault-finding tool equipped with the vehicle diagnostic
probe (part no.: Elé. 1674).
Note:
The multiplex network of the vehicle is the main functional communication network of the vehicle. But
certain optional functions are still performed by track wires.
IMPORTANT
However, the Scénic II still uses two different physical fault finding media:
●The multiplex network: which allows fault finding of the following computers: instrument panel, electric
power assisted steering, airbag, automatic air conditioning, UCH, anti-lock braking system - electronic
stability program, protection and switching unit, injection.
●K / L lines diagnostic network: for fault finding on the following computers: automatic transmission,
automatic parking brake, discharge bulbs and parking assistance.
Some other computers, while connected to the vehicle's multiplex network, have their own "self-test" function:
central communications unit (Carminat), driving school unit or that cannot be diagnosed with the tool: steering
lock (governed by the UCH).
IMPORTANT
Computer supply for the fault finding procedure:
To run fault finding on the vehicle computers, proceed as follows:
●Vehicle card in card reader
●Press and hold start button (longer than 5 seconds) with start-up conditions not fulfilled,
●Connect the diagnostic tool and perform the required operations.
