88B-4V3 MR-413-X44-88B000$010.mif
MULTIPLEXING
Fault finding – Introduction88B
MULTIPLEX NETWORK TEST PROCEDURE
–Establish dialogue with the computers storing the vehicle configuration (read identification).
–Read the vehicle configuration in the two computers that store the multiplex network configuration (UCH and
Airbag) for the Vehicle multiplex line network.
–Read the vehicle configuration in the computer that stores the multiplex network configuration (A2/A3 display
computer) for the Multimedia multiplex line network.
–List of computers which support fault finding read from the two configuration computers.
–Computer interrogation.
–Physical (electrical) measurements on the multiplex line network.
IMPORTANT
There are three diagnostic lines, depending on the vehicle options:
Fault finding on the computer using the vehicle multiplex network:
–Injection systems,
–ABS or ABS/ESP or vehicle speed computer (depending on the vehicle equipment),
–UCH,
–Automatic transmission (depending on the vehicle equipment),
–Lighting (depending on the vehicle equipment),
–Instrument panel,
–Airbag/pretensioners,
–Climate control (depending on the vehicle equipment),
–Driving school unit (depending on the vehicle equipment),
–LPG injection (depending on the vehicle equipment).
Fault finding on computers using the multimedia multiplex network (depending on the vehicle equipment):
–Radio (R1-08 or R2-08),
–Multimedia interface (A2/A3 display),
–Multimedia connection (C-box).
Fault finding on the computer using the K line (depending on the vehicle equipment):
–Parking distance control and power-assisted steering.
88B-8V3 MR-413-X44-88B000$020.mif
88B
Multiplexing enables signals to be sent between different computers on the vehicle, such as:
119 Automatic transmission computer 756 Airbag pretensioners/computer
120 Injection computer 995 Electronic rev counter
247 Instrument panel 1094 ABS/ESP computer
419 Air conditioning computer 1222 Parking distance control computer
502 Power-assisted steering computer 261 Radio
645 UCH 225 Diagnostic socket
653 Multimedia interface (A2/A3 display) 1959 Multimedia connection (C-box)
1222 247 995
502
645
120 119 65310941959
225261419
756
MULTIPLEXING
Fault finding – List and location of components
