Self-Study Program

53
Reference
For a detailed description of the basic
functions of the DSP, refer to SSP 284
(page 36 onwards).
367_078
Starter inhibitor/starter control
The starter control/starter inhibitor function is
implemented via entry and start authorisation
control unit J518.
The P/N signal (ground), a requirement for start
enabling, is generated by a separate switch in the
multi-function switch F125.
The P/N signal is transmitted to J518 via a discrete
line.
J518 only enables the engine control unit J623 to
activate terminal 50 in selector lever position "P" or
"N".
For self-diagnostic purposes, the selector lever
position is also indicated to J518 via the databus.
Distributed functions in the Audi Q7
As a modern automatic gearbox, the 09G also
features the latest generation of the Dynamic
Shift Program (DSP).
DSP evaluates vehicle operating parameters such as
motion resistance (e.g. uphill gradient), route profile
(e.g. corner) and driver type (driving style).
The main parameters used to compute the gear
selection have not changed fundamentally
compared to previous automatic gearboxes.
Due to the increasing networking of the gearbox
control unit and other vehicle systems, such as
engine, ESP and steering angle sensor, today a
larger volume of information is available, providing
an even better description of momentary driving
status and driving style for the gearbox control unit.
Reversing switch F41
The reversing switch F41 is integrated in the multi-
function switch F125. F41 supplies a voltage signal
(R signal) to the onboard power supply control unit
J519 and other control units which utilise the
R signal.
The R signal is required for the following functions
and systems:
– Reversing light
– Anti-dazzle rear-view mirror
– Self-diagnosis of gearbox control unit J217
The reversing light is activated by the convenience
system central control unit 2 J773.
The information path is as follows:
reversing switch F41 > discrete line to onboard
power supply control unit J519 > to convenience
system central control unit 2 J773 via convenience
CAN > discrete line to reversing light.
The R signal is also sent to the gearbox control unit
J217 via a discrete line.
The self-diagnostics in J217 utilise the R signal to
check the plausibility of the multi-function switch
F125.
If the R signal is faulty, the gearbox enters limp-
home mode.
Dynamic Shift Program DSP
Multi-function switch F125
Switch for P/N signal
F41