14
The data bus diagnostic interface retains
diagnostic capability even without terminal 15
ON. This is however subject to the restriction
that no write operations, such as encoding, can
be implemented.
The ignition must be on for starting diagnosis,
as the 500 kbit/s diagnosis CAN has no wake-
up capability.
If a control unit is in one wire mode, this is
indicated by "1 wire". In the Audi A8 ´03, the
measured value block for one-wire diagnosis
is only available in the diagnostic interface.
The "sleep readiness" of the control units is
indicated by "S". If the vehicle is in diagnosis
mode, the bus systems do not switch to sleep
mode even if all control units are indicating
"sleep readiness".
Diagnosis
The data bus diagnostic interface enables
data to be exchanged between the diagnosis
unit and the individual control units in the
vehicle. In this process, the control unit
diagnosis data are transmitted via the
corresponding data bus system to the
diagnostic interface and from there via the
diagnostic connector to the diagnosis unit
(refer to SSP 286 under "Diagnosis CAN",
Page 50).
Measured value blocks
The data bus diagnostic interface is provided
with measured value blocks in which
communication, one-wire diagnosis and
sleep mode are displayed.
If there is communication with a control unit
fitted in the vehicle, this is indicated in the
measured value block by a 1. If there is no
communication with a control unit fitted in
the vehicle or encoded, this is indicated by
a 0.
Control Units
SSP287_010
Assisted fault-finding
Functional test
Audi V05.02 18/06/2002
Audi A8 2003>
2003 (3)
Saloon
BFM 4.2l Motronic / 246 kW
Measured value block 130
Two-wire
Convenience data bus
Electr. CE 1
Electronic central electrics
Central 0
Convenience system central module
Driver's door 1 wire
Driver's door electronics
Measurement Jump Print Help
J533 - Display measured value
blocks
1.Functional
description
