navigation system RENAULT TWINGO RS 2009 2.G Electrical Equipment - Multiplexing Workshop Manual

88B-2V3 MR-413-X44-88B000$010.mif
88B
INTRODUCTION
Description of the multiplex network:
The multiplex network consists of a twisted pair of wires connected to several vehicle computers.
These two wires are called multiplex line H and multiplex line L.
Depending on the vehicle options, there is a single multiplex network.
–the Vehicle multiplex line (injection, anti-lock braking system/electronic stability program, instrument panel, air
conditioning, rev counter, sequential gearbox, UCH, airbag/pretensioners) is always present,
–the Multimedia multiplex line (navigation, radio, display, hands-free telephone) depending on the vehicle options.
Data is exchanged by the computers on the Vehicle multiplex line and Multimedia multiplex line networks at a
communication speed of 500 kbit/s.
The Vehicle multiplex line network has two computers, each with an internal resistance of 120ΩΩ Ω Ω

(network terminating resistors):
–the injection computer,
–the airbag computer.
The Multimedia multiplex line network has two computers, each with an internal resistance of 120ΩΩ Ω Ω

(network terminating resistors):
–the A2/A3 display,
–the radio.
PURPOSE
–The purpose of the multiplex network test is to determine the computers present on the vehicle's multiplex network
as well as the cause of possible inter-computer communication faults.
–It also serves to determine the functions installed in the vehicle which are often housed in various computers
(distributed functions, e.g.: Air conditioning, Security access, etc.).
–The test also checks the condition of multiplex network segments.
–The multiplex network test can also run fault finding on computers disconnected from the multiplex network; this
provides an overview of the vehicle's electronic layout. Note:
The Vehicle and Multimedia multiplex line networks support fault finding using the RENAULT tool.
MULTIPLEXING
Fault finding – Introduction