Audi Q7 User manual

Audi
Service Training
Audi Q7 (type 4M)
Occupant protection and infotainment
Self Study Programme 637
For internal use only

2
Occupant safety
Passive safety
A new airbagcontrol unit J234 was developed for occupant protec-
tion in the AudiQ7 (type4M). It contains a sensor which measures
rotation about the Z axis. In addition, the airbagcontrol unit J234
now communicates via the FlexRay bus with other control units
such as the ABS control unit J104. The ABScontrol unit J104 thus
receives in real time data on rotation about the Z axis which is
utilised by the Electronic Stability Control (ESC) system.
Depending on country and trim level, pyrotechnic seat belt ten-
sioners can be installed in the 3rd seat row of the AudiQ7 as an
option.
Active safety
Depending on country, 4Audipresensefunctions are optional for
the AudiQ7. In additional to Audi pre sense basic, these are:
• presenserear
• presensefront
• presensecity
Audi pre sense city is able to warn the driver about vehicles and
pedestrians and brake within system limitations. Audipre sense
front brings to the Audi Q7 new functions such as evasion assist
and turn assist.
Learning objectives of this self study programme:
This self study programme describes the occupant protection and
infotainment systems of the AudiQ7 (type4M). Once you have
completed this self study programme you will be able to answer
questions on the following topics:
• New passive safety features
• New active safety features
• Modifications to and new features of the infotainment system
637_097
Infotainment
Audi oers various levels of the infotainment modules for the
AudiQ7. MMIRadioplus is standard in Germany. This oers
interfaces for external devices such as mobile phones or memory
cards. The Audi sound system delivers excellent sound quality from
its ten speakers. It is controlled using the MMI terminal on the
center tunnel.
MMI navigation plus also includes the module Audi connect, which
connects the Audi Q7 to the Internet via the LTE standard. Rear
passengers can surf via the WiFi hotspot with download speeds of
up to 100 Mbit/s and send and receive e-mail. The driver can use
the customised Audi connect services ranging from online trac
information to navigation with Google Earth and Google Street
View to online media streaming.
Audi pre sense
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3
Passive safety
Overview _____________________________________________________________________________________________________________________________________________________ 4
Components _________________________________________________________________________________________________________________________________________________ 4
System overview ____________________________________________________________________________________________________________________________________________ 6
Centre crash sensor for X/Y axis G858 ____________________________________________________________________________________________________________________ 8
Airbag control unit J234 ____________________________________________________________________________________________________________________________________ 8
Seat belts ___________________________________________________________________________________________________________________________________________________12
Lap belt tensioner with buckle ____________________________________________________________________________________________________________________________ 16
Active safety
Audi pre-sense ______________________________________________________________________________________________________________________________________________18
Pre sense basic _____________________________________________________________________________________________________________________________________________ 18
Pre sense rear _______________________________________________________________________________________________________________________________________________21
Pre sense front _____________________________________________________________________________________________________________________________________________24
Pre sense city _______________________________________________________________________________________________________________________________________________30
Settings and displays ______________________________________________________________________________________________________________________________________34
Infotainment
Overview of versions _______________________________________________________________________________________________________________________________________44
Second-generation MIB Standard ________________________________________________________________________________________________________________________46
MMI radio ___________________________________________________________________________________________________________________________________________________47
MMI Radio plus _____________________________________________________________________________________________________________________________________________48
MMI Navigation plus _______________________________________________________________________________________________________________________________________ 49
Audi connect (depending on market) ____________________________________________________________________________________________________________________50
Control panel _______________________________________________________________________________________________________________________________________________51
Display mechanism ________________________________________________________________________________________________________________________________________54
Audi phone box _____________________________________________________________________________________________________________________________________________57
Network system ____________________________________________________________________________________________________________________________________________58
Sound systems _____________________________________________________________________________________________________________________________________________60
Aerials overview ____________________________________________________________________________________________________________________________________________ 66
Appendix
Test your knowledge _______________________________________________________________________________________________________________________________________69
Self study programmes ____________________________________________________________________________________________________________________________________71
Reference
NoteThe self study programme teaches a basic understanding of the design and mode of operation of new models,
new automotive components or new technologies.
It is not a repair manual! Figures are given for explanatory purposes only and refer to the data valid at the
time of preparation of the SSP. This content is not updated.
For further information on maintenance and repair work, always refer to the current technical literature.
Contents

4
Components
Depending on country version and trim level, the passive occupant
and pedestrian protection system in the Audi Q7 can comprise the
following components and systems:
• Airbag control unit
• Adaptive driver airbag
• Adaptive front passenger airbag
(front passenger airbag, two-stage country version)
• Front side airbags
• Rear side airbags (equipment option)
• Head airbags
• Front airbag crash sensors
• Crash sensors for side impact detection in the doors
• Crash sensors for side impact detection in the C posts
• Crash sensor for side and longitudinal impact detection
• Centre pedestrian protection crash sensor
(acceleration sensor, country version)
• Left and right pedestrian protection crash sensors
(pressure sensors, country version)
In-vehicle airbags
Front pass. airbag Front side airbagDriver airbag
Front side airbag
• Front inertia-reel seat belts with pyrotechnic belt tensioners
• Front inertia-reel seat belts with electrical belt tensioners
• Front inertia-reel seat belts with active belt force limiters
• Inertia-reel seat belts for second seat row with pyrotechnic belt
tensioners, driver and front passenger sides (country version)
• Inertia-reel seat belts for third seat row with pyrotechnic belt
tensioners, driver and front passenger sides (country version)
• Front lap belt tensioner (country version)
• Seat belt warning for all seats (country version)
• Seat occupancy sensor in front passenger seat
• Front pass. airbag disabling switch (country version)
• Front pass. airbag OFF and ON warning lamp
• Driver and front passenger seat position sensors
• Pedestrian protection trigger (country version)
• Battery isolator
Overview
On the following pages you will find a summary of the occupant
protection system in the Audi Q7.
Passive safety
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5
Note
The diagrams in the chapter "Passive occupant safety" are schematic diagrams and aid understanding.
637_007
Front side airbag Head airbag,
driver and front passenger side
Rear side airbag
Rear side airbag
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6
637_009
System overview
The system overview shows the components for all markets. Keep in
mind that this constellation is not possible in volume production.
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7
Additional equipment
Equipment specifications can vary due to the dierent require-
ments and statutory provisions for car makers in the various
markets.
Key to figure on page6:
E24 Driver side seat belt switch
E25 Front pass. side seat belt switch
E224 Airbag disabling switch, front passenger side
F390 Driver side seat belt switch, 2nd seat row
F391 Centre belt switch, 2nd seat row
F392 Front pass. side seat belt switch, 2nd seat row
F393 Driver side seat belt switch, 3rd seat row
F395 Front pass. side seat belt switch, 3rd seat row
G128 Passenger side seat occupancy sensor
G179 Side airbag crash sensor, driver side
G180 Side airbag crash sensor, front passenger side
G256 Rear side airbag crash sensor, driver side
G257 Rear side airbag crash sensor, passenger side
G283 Front airbag crash sensor, driver side
G284 Front airbag crash sensor, front passenger side
G551 Belt force limiter, driver side
G552 Belt force limiter, front passenger side
G553 Seat position sensor, driver side
G554 Seat position sensor, front passenger side
G598 Pedestrian protection trigger 1
G599 Pedestrian protection trigger 2
G693 Pedestrian protection crash sensor, centre
G851 Driver side crash sensor for pedestrian protection 2
G852 Passenger side crash sensor for pedestrian protection 2
G858 Centre crash sensor for X/Y axis
J234 Airbag control unit
J285 Control unit in dash panel insert
J533 Data bus diagnostic interface (gateway)
J706 Seat occupancy recognition control unit
J854 Front left seat belt tensioner control unit
J855 Front right seat belt tensioner control unit
K19 Seat belt reminder warning lamp
K75 Airbag warning lamp
K145 Front pass. airbag OFF warning lamp (ON and OFF status of
the front passenger airbag is indicated)
N95 Driver side airbag igniter
N131 Front pass. side airbag igniter 1
N132 Front pass. side airbag igniter 2
N153 Seat belt tensioner igniter 1, driver side
N154 Seat belt tensioner igniter 1, front passenger side
N196 Rear seat belt tensioner igniter, driver side
N197 Rear seat belt tensioner igniter, front passenger side
N199 Side airbag igniter, driver side
N200 Side airbag igniter, front passenger side
N201 Rear side airbag igniter, driver side
N202 Rear side airbag igniter, passenger side
N251 Head airbag igniter, driver side
N252 Head airbag igniter, front passenger side
N253 Battery isolation igniter
N297 Seat belt tensioner igniter 2, driver side
(lap belt tensioner)
N298 Seat belt tensioner igniter 2, passenger
side (lap belt tensioner)
N490 Driver airbag relief valve igniter
N491 Front pass. airbag relief valve igniter
N668 Driver side seat belt tensioner igniter, 3rd seat row
N669 Front pass. side seat belt tensioner igniter, 3rd seat row
T16 16-pin connector, diagnostic port
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8
XY
Centre crash sensor for X/Y axis G858
The centre crash sensor for X/Y axis G858 is an acceleration sensor.
A combination sensor, the centre crash sensor for X/Y axis, meas-
ures both vehicle acceleration and deceleration in the Y and Y
directions.
The centre crash sensor for X/Y axis is used to validate the plausi-
bility of defined crash situations in the longitudinal (X) and trans-
verse directions (Y).
Installation location
In the AudiQ7, the centre crash sensor for X/Y axis G858 is located
on the centre tunnel rear in proximity to the rear cross member for
the driver's seat.
637_011
637_010
Airbag control unit J234
Sensors and data bus interface
The airbag control unit J234 in the Audi Q7 has undergonme
extensive modification.
The sensors which measure acceleration in the X and Y directions
and yaw rate about the vehicle's Z axis (inertial sensors) are now
positioned directly on the airbag control unit J234. To enable the
ESC signals to be transmitted on the data bus with guaranteed
minimum reaction time of about 2 ms, the control unit was
rerouted from the powertrain CAN bus to the FlexRay bus.
In functional terms, therefore, the airbag control unit J234 records
body movement and provides this data via the FlexRay bus to ABS
control unit J104, among others. The ABS control unit J104 is also
connected to the FlexRay bus. The ABS control unit processes the
data it receives from the airbag control unit and takes the appro-
priate action, e.g. stabilision of vehicle by corrective braking
(ESCcontrol).
Centre crash sensor
for X/Y axis
G858
Airbag control unit
J234
Coordinates
637_050
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9
X
Z
Y
637_013
637_014 637_015
Measurement of longitudinal vehicle movement in X, Y and Z directions
The sensors for the measurement of longitudinal vehicle move-
ment in X, Y and Z directions work on the "seismic mass" principle.
Capacitor plate
(movably mounted)
Seismic mass
Spring element
Capacitor plate
(stationary)
Housing
Direction of measurement
Design of the sensor
A movably mounted mass (seismic mass) is integrated in the
sensor at a defined distance to a stationary capacitor plate acting
as an electrode. The seismic mass also has electrodes, which
combine with the stationary electrodes to form a capacitor.
An acceleration force acting on the sensor changes the position of
the seismic mass relative to the stationary capacitor plate due to
inertia. This, in turn, changes the physical magnitude of the capaci-
tance, which is processed digitally and evaluated accordingly.
Rest position Movement
Coordinates
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X
Z
Put in simple terms, therefore, the sensor consists of a microme-
chanical body which is permanently subjected to oscillation excita-
tion.
When the vehicle turns, the direction of movement of the oscillat-
ing body changes. These deflections relative to the direction of
movement (changes in movement) are processed digitially and
evaluated accordingly.
To measure rotation about the X and Z axes, a rollover sensor (for
rollover detection) and an inertial sensor (for ESC signal indicating
yaw rate about Z) are arranged at a 90° oset relative to each
other in the airbag control unit J234.
Airbag control unit J234
637_016b
Measurement of vehicle rotation about the X and Z axes
The sensors for the measurement of vehicle rotation about the X
and Z axes work on the "Coriolis force" principle.
When the disc rotates while the ball is rolling on the platform,
however, the ball is deflected in the direction of motion of the disc.
The degree of deflection depends on the rotational speed of the
disc.
637_012
637_016a
The Coriolis force acts on all bodies that move within a rotating
reference system. The eect of the Coriolis force is demonstrated
in the example given here. A ball is rolled on a disc. When the disc
is stationary the ball rolls straight across it.
637_088
Coordinates
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Activation of the electrically reversible seat belt tensioners
If corrective adjustments are made by Audipresense, the
airbagcontrol unit J234 initiates tensioning of the electrically
reversible seat belt tensioners via the front left seat belt tensioner
control unit J854 and the front right seat belt tensioner control
unit J855. Seat belt tensioners J854 and J855 are connected to the
airbag control unit via a sub-bus system. Refer to page18 for further
information about Audipresense and to page12 for further infor-
mation about the reversible seat belt tensioners.
637_008
637_018
Terminal 30
Diagnostics
The airbagcontrol unit J234 is a terminal 30 control unit and is
discretely connected to terminal 30 and terminal 15. It addition-
ally receives digital information on the status of terminal 15 via
the data bus diagnostic interface J533 (gateway). The airbag
system is only deploys when the ignition is on (terminal 15 on).
A capacitor is integrated in the control unit J234. If terminals 15
and 30 are disconnected, this capacitor enables the dierent
pyrotechnic components (e.g. airbags, seat belt tensioners) to
deploy. If only terminal 15 is disconnected, the control unit is still
supplied by terminal 30 (continuous pulse). This allows the various
pyrotechnic components to be initiated by the vehicle battery,
making even longer deployment times possible.
The diagnostic address of the airbagcontrol unit J234 is
"15–Airbag". The generation of control units (system designation)
is "Airbag10.44" and can be retrieved in the Guided Fault Finding
under "Control unit identification".
Since the installed position of the airbagcontrol unit J234 can have
tolerances, the inertial sensors can be calibrated in order to
measure acceleration in the X and Y directions and the yaw rate
about the Z axis.
If a new airbagcontrol unit J234 has been installed but the basic
setting procedure has not yet been carried out, the event
"C115E54 - inertial sensors - no basic setting" is entered into the
fault memory.
During subsequent work basic setting of the inertial sensors of
airbag control unit J234 must be carried out using the Guided Fault
Finding function.
• If control unit J234 was removed and installed.
• If control unit J234 is replaced.
Key:
A Battery
J234 Airbag control unit
J367 Battery monitor control unit
J519 Onboard power supply control unit
J533 Data bus diagnostic interface
Data bus
diagnostic interface
J533
Airbag control unit
J234
Control unit for
front left seat belt
tensioner
J854
Seat occupancy
recognition control unit
J706
Control unit for
front right seat belt
tensioner
J855
Extract from the topology
Function diagram
LIN bus
FlexRay
LIN bus
FlexRay
Sub-bus
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12
Seat belts
Front automatic belt retractor
Depending on country version and trim level, 2 dierent automatic
belt retractors are used on the Audi Q7.
• Automatic belt retractor with seat belt tensioner and active
belt force limiter
• Automatic belt retractor with belt tensioner, reversible seat
belt tensioner and active belt force limiter
If the vehicle is equipped with Audipresensebasic, the front
automatic belt retractors are equipped with pyrotechnic belt
tensioners, with active belt force limiters and with reversible seat
belt tensioners with electric motors.
The reversible seat belt tensioners, front left seat belt tensioner
control unit J854 and front right seat belt tensioner control units
J855 are connected to the airbag control unit J234 via a sub-bus
system. Seat belt tensioner control units J854 and J855 are purely
actuators. They have no "intelligence" and are activated by the
airbag control unit.
When Audi pre sense basic detects specific driving situations,
corresponding signals are sent to the data bus. The airbag control
unit evaluates the signals and, if necessary, instructs the seat belt
tensioner control unit to partially or fully tension the seat belts via
an electric motor. For further information about Audi pre sense,
refer tothe chapter "Active safety" on page18.
The automatic seat belt retractors use pyrotechnic ball tensioners.
If an automatic seat belt retractor with reversible seat belt ten-
sioner is replaced, it is not necessary to carry out basic setting
using the Guided Fault Finding system.
637_085
Outer automatic seat belt retractors of the 2nd and 3rd seat rows
Depending on country version and trim, the automatic seat belt
retractors of the 2nd and 3rd seat rows are equipped with pyro-
technic belt tensioners.
The automatic seat belt retractors use pyrotechnic push rod ten-
sioners.
637_087
Automatic seat belt
retractor 3rd seat row
Reversible belt tensioner
with electric motor
Pyrotechnic seat
belt tensioner
Active belt force limiter
Automatic seat belt
retractor 2nd seat row
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Push rod tensioner
Design
637_098
637_100
5-piece flexible push rod made of
plastic "Snake" (5)
Guide tube/pressure chamber (3)
Belt retractor shaft as torsion bar
spring (6)
Gear (7)
Guide (8)
Piston (2) with:
• seal
• stopper
• spacer
Plugged electrical connection (1) with:
• igniter
• pyrotechnic propellant charge
Braking wedge
(4)
Piston (2) and push rod "Snake" (5)
The guide tube/pressure chamber (3), refer to Fig. 637_098,
accomodates the following:
• Plugged electrical connection with igniter and pyrotechnic
propellant charge (1)
• 5-piece flexible push rod "Snake" (5) and "Snake" guide
• Pressure chamber (3)
• Braking wedge (4)
• Piston (2) (including seal, stopper and spacer)
Piston (2) with:
• seal
• stopper
• spacer
4 short parts of the "Snake" Main part of the "Snake"
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Function
When the airbag control unit J234 ignites the pyrotechnic propel-
lant charge (1) of the push rod tensioner, the combustion of the
propellant charge leads to a sudden rise in pressure inside the
guide tube/pressure chamber (3). Due to the pressure rise, the
piston (2) and the "Snake" (5) are pushed down.
637_101
637_102
After the "Snake" (5) has moved out of the guide tube, it meets the
gear (7) which is firmly connected to the retractor shaft (6). The
teeth of the gear mesh with the "Snake" due to the material
characteristics and geometry of the components. The "Snake" is
pushed further down and causes the gear together with the retrac-
tor shaft to rotate.
Pyrotechnic pro-
pellant charge (1)
"Snake" (5)
"Snake" (5)
Guide tube/pres-
sure chamber (3)
Retractor shaft (6)
Piston (2)
Gear (7)
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As the seat belt is firmly connected to the belt retractor shaft (6),
the seat belt is retracted and tensioned. To esnure that the belt
force exerted on the occupants stays within a defined range, the
belt force is limited. The belt force is limited by the retractor shaft
(6), which is configured as a torsion bar spring. The "Snake"(5) is
moved to the side by the guide (8) in a controlled manner. The
distance which the piston (2) travels is limited by the stopper
which moves up against the braking wedge (4).
637_103
637_104
When the stopper (2) has reached the end of its travel envelope,
the long part of the "Snake" (5) protrudes a defined distance from
the guide tube/pressure chamber (3). At this point, 4 short parts
of the "Snake" come into contact with the gear (7). Due to the
5-piece design of the "Snake", the 4 short parts displace and push
the "Snake" in such a way that the gear and the retractor shaft (6)
are again free. The belt tensioning process is now complete.
"Snake" (5)
Gear (7)
Guide (8)
Braking
wedge (4)
Piston (2)
Piston with
stopper (2)
"Snake" (5)
Guide tube/pres-
sure chamber (3)
Retractor
shaft (6)
Retractor
shaft (6)
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Lap belt tensioner with buckle
Depending on country version, the AudiQ7 is equipped with lap
belt tensioners, igniter for seat belt tensioner 2 driver side N297
and igniter for seat belt tensioner 2 front passenger side N298 on
the driver and front passenger sides.
If lap belt tensioners are fitted, the seat belt of the automatic belt
retractor also comes fitted with a buckle.
When the seat belt is being worn, the lap belt tensioner in combi-
nation with the buckle performs the following tasks in the event of
an accident which meets the criteria for deployment:
• Separation of the force acting on the pelvis from the force
acting on the thorax
• Reduced chest compression
• Reduced upper thigh load
• Reduced forward displacement of the pelvis
• Improved interfacing between the pelvis and seat
637_044
Buckle
Automatic belt retractor
Belt deflector
Lap belt tensioner
Coupling
Accident response sequence
In the event of an accident which meets the criteria for deploy-
ment, the airbag control unit deploys the seat belt tensioners and
the lap belt tensioners. The seat belt is tensioned from the buckle
on up by the belt tensioner on the automatic belt retractor. For
safety reasons, the belt force is limited by the active belt force
limiter.
The lap belt tensioner tensions the part of the seat belt between
the occupant's pelvis and the buckle.
637_045
Seat belt travel
Overview
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Diagnostics
The lap belt tensioner is a pyrotechnic component. The safety
instructions are the same as for other pyrotechnic components.
Refer to the relevant service literature. The lap belt tensioner is
damaged when ignited and has to be replaced as a unit.
The airbag control unit J234 continuously monitors the lap belt
tensioners for proper functioning. Faults in the system are regis-
tered by the airbag control unit as event memory entries. These
faults can be cleared using the "Guided Fault Finding".
Buckle
The dierence between this seat belt buckle and a "regular" seat
belt buckle is that it locks the belt in the event of an accident which
matches the criteria for deployment. The result is a load path for
the thorax region and a load path for the pelvic region, with all the
aforementioned benefits for the occupants.
637_047
Belt deflector
Foam pad
Steel cable of the
lap belt tensioner
637_048
Seat belt join
Coupling
The seat belt is deflected in the area of the B post and, unlike in
other vehicles without lap belt tensioners, is able to move
upwards. A coupling is stitched to the end of the seat belt. The lap
belt tensioner coupling is inserted into the seat belt coupling and
clipped into place. To insulate against noise, a foam pad is fitted in
the coupling area.
Coupling
Installation location of the lap belt tensioner
The lap belt tensioner is installed in the B post. For this purpose,
the lugs on the lap belt tensioner are integrated in the B post and
bolted into place.
637_046
Lug engaged
in the B post
Lap belt tensioner
On L/H side
of the vehicle
Reference
For further information about the function of the lap belt tensioner with buckle, refer to Self Study Programme 625
"AudiA3saloon".
Lap belt tensioner
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Audi pre-sense
Audipresense is, within its system parameters, able to initiate
actions to protect the occupants and other road users in certain
critical situations. For this purpose, the vehicle and its occupants
are prepared for a potentially imminent collision.
This is made possible by networking the various in-car systems.
The systems send data continuously to the data bus. Other control
units are able to evaluate this information and take appropriate
action.
Audipresense is available in the following versions for the
AudiQ7.
Depending on market, Audipresensebasic/rear and
Audipresensecity may be standard equipment. If this is not the
case, Audipresensebasic, presensecity, presenserear and
presensefront are optional.
Please note that Audi pre sense cannot prevent collisions. It serves
only to assist the driver and it can reduce the severity of the colli-
sion. It should also be noted that not all objects or lane makings
can be detected by the sensor or by the camera.
The individual functions of Audipresense are described in greater
detail below.
Audi pre-sense basic PR no. 7W1
Audi pre sense city PR no. 6K8
Audi pre-sense front PR no. 8T3 / 8T8
Audi pre sense rear
inclusive of pre sense basic
PR no. 7W3
Pre sense basic
With Audipresensebasic, the following actions can be initiated:
• Belt slack reduction
• Partial or full tensioning of the electrically reversible seat
belt tensioners
Definition and function of belt slack reduction system for reversible seat belt tensioners
In certain situations, e.g. when wearing a thick winter jacket, it
may be the case that the seat belt is not tight fitting to the body
after the reversible seat belt tensioners deploy. In such a case, the
mechanical unreeling force of the automatic seat belt retractor is
less than the force required to compress the thick winter jacket.
The distance which the seat belt can travel until it fits the front
occupants perfectly is referred to as "belt slack".
637_004
• Closing the panoramic glass sunroof2)
• Closing the side windows
• Switching on the hazard warning flashers1)
1) Not available in all countries.
2) Optional equipment.
637_005
The seat belt is unreeled with defined force by the reversible seat
belt tensioners under the following conditions. This enables any
existing belt slack to be reduced.
• If the vehicle reaches a speed of about 15 kph after starting the
engine and travelling forwards.
• If the vehicle has not reached a speed of 15kph about
10seconds after starting the engine and travelling forwards.
Seat belt fits rightly
(minimum belt slack)
Seat belt on "thick" clothing
(more belt slack)
Active safety
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System characteristics of the reversible seat belt tensioners
• After reducing seat belt slack, the seat belt is released again.
• If a seat belt is not worn, slack is not reduced for this seat belt.
• If thr front passenger airbag is "o", slack is not reduced on the
front passenger side.
Longitudinal dynamics function
• The reversible seat belt tensioners, front left seat belt tensioner
control unit J854 and front right seat belt tensioner control
units J855 are connected to the airbag control unit J234 via a
sub-bus system. The airbag control unit J234 instructs the seat
belt tensioners to reduce the belt slack.
• In the case of Audipresensebasic, tensioning of the reversible
seat belt tensioners can take place at a speed of higher than
30kph when the longitudinal and transverse dynamics func-
tions are active. To activate longitudinal dynamics, the vehicle
must be moving forwards.
An exception here is the crash function in the low relative speed
range (refer to page20).
Hazard braking
If the brake pressure reaches a defined value during a hazard
braking manoeuvre, Audipresensebasic initiates electrical partial
tensioning of the reversible seat belt tensioners. A message
indicating that Audipresense is active appears in the instrument
cluster. No audible signal is given.
Emergency braking
During an emergency braking manoeuvre, the seat belt tensioners
are either partially or fully tensioned. Depending on the situation,
the ABS control unit J104 can instruct the hazard warning flash-
ers1) to be activated. A distinction is made between the following
two criteria for emergency braking.
• An emergency braking situation exists if the ABS control unit
J104 detects that brake pressure had reached a specific value
within a defined period of time. If the conditions are met, Audi
presensebasic initiates electrical full tensioning of the revers-
ible seat belt tensioners. A message indicating that
Audipresense is active appears in the instrument cluster. No
audible signal is given.
1) Not available in all countries.
System characteristics
• If Electronic Stability Control (ESC) is set to "lift/oroad" of
"o" using the TCS/ESP button E256, the seat belts are not
partially tensioned.
• If Audidriveselect is set to "dynamic" or "lift/oroad", the
seat belts are not partially tensioned.
• If Audipresense is switched o in the MMI, the seat belts are
not partially tensioned either.
• An emergency braking situation exists if the given conditions
are not met, but if the ABS control unit J104 has detected an
emergency braking manoeuvre based on the pedal rates. If the
conditions are met, Audi presensebasic initiates electrical
partial tensioning of the reversible seat belt tensioners.
Amessage indicating that Audipresense is active appears in
the instrument cluster. No audible signal is given.
637_019
Drive profile selection
switch module
E592
TCS/ESP button
E256
637_041
Audi pre sense
Operating unit 1 for drive and comfort/
convenience functions
E791
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20
Transverse dynamics function
If the vehicle oversteers or understeers, the Electronic Stability
Control (ESC) will try to stabilise the vehicle. If the vehicle
becomes unstable because certain physical limits have been
exceeded, the airbag control unit J234 initiates partial tensioning
of the electrically reversible seat belt tensioners. A message
indicating that Audipresense is active appears in the instrument
cluster. No audible signal is given.
If the vehicle can no longer be stabilised, the following actions are
initiated:
• The electrically reversible seat belt tensioners are fully ten-
sioned. A message indicating that Audipresense is active
appears in the instrument cluster. No audible signal is given.
• The side windows and the panoramic glass sunroof2) are closed
when the seat belts are fully and partially tensioned.
• When the seat belts are fully and partially tensioned, the
hazard warning flashers1) are activated as long as the vehicle is
unstable.
System characteristics
• If Audidriveselect is set to "dynamic" or "lift/oroad", the
seat belts are not partially tensioned.
• If Audipresense is switched o in the MMI, the seat belts are
not partially tensioned either.
• If the vehicle is unstable, if the Electronic Stability Control is set
to "lift/oroad" or "o" and if the driver actively applies the
brakes, the seat belts are fully tensioned. A message indicating
that Audipresense is active appears in the instrument cluster.
No audible signal is given. The side windows and the panoramic
glass sunroof2) are closed. The hazard warning flashers1) are
activated as long as the vehicle is unstable.
Crash function in the low relative speed range
If the airbag control unit J234 detects a head-on collision at a low
relative speed3) and at a low rate of vehicle deceleration, the airbag
control unit decides situation-specifically on the basis of the
control unit algorithm whether to initiate electrical full tension-
ing.
If the above-mentioned conditions apply, pyrotechnic components
such as the airbags do not deploy. No further actions are initiated,
e.g. activation of the hazard warning flashers1), closing of the side
windows or the panoramic glass sunroof2).
1) Not available in all countries.
2) Optional equipment.
3) The relative speed is the dierence in speed between one's own vehicle and the following vehicle.
637_041
Audi pre sense
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