air suspension AUDI A5 COUPE 2012 Owners Manual

dealer is familiar with these requirements
and we recommend that you have your
dealer perform this service for you.
Other things that can affect Advanced
Airbag performance
Changing the vehicle's suspension system can
change the way that the Advanced Airbag Sys­
tem performs in a crash. For example, using
tire-r im combinations not approved by Audi,
lowering the vehicle, changing the stiffness of
the suspension, including the springs, suspen­
sion struts, shock absorbers etc. can change
the forces that are measured by the airbag sensors and sent to the electronic control
unit. Some suspension changes can, for exam­
ple, increase the force levels measured by the
sensors and make the airbag system deploy in
crashes in which it would not deploy if the
changes had not been made . Other kinds of
changes may reduce the force levels meas­
ured by the sensors and prevent the airbag
from deploying when it should .
The sensors in the safety belt buckle for the
d river and front passenger seat tell the elec­
tronic control module if the safety belt is
latched or not. If the safety belt is being used,
the front airbag will deploy at a slightly high­
er rate of vehicle deceleration than if the safe ­
ty belt is not being used. Therefore, in a par­
ticular collision, it is possible that an airbag
will not deploy at a seating position where the safety belt is being used but will inflate at the
position where the safety belt is not being
used. It is important that nothing interfere
with the safety belt buckles so that the sen­
sors can send the correct information about
safety belt use to the electronic control unit.
.&_ WARNING
Changing the vehicle 's suspension includ­
ing use of unapproved tire-rim combina­
tions can change Advanced Airbag per­
formance and increase the risk of serious personal injury in a crash.
- Never install suspension components
that do not have the same performance
Airbag system 177
characteristics as the components origi­
nally installed on your vehicle .
- Never use tire-rim combinations that
have not been approved by Audi.
.&_ WARNING
= -
Items stored between the safety belt buckle and the center console can cause
the sensors in the buckle to send the
wrong information to the electronic con ­
trol module and prevent the Advanced Air­ bag System from working properly.
-Always make sure that nothing can inter-
fere with the safety belt buckles and that
they are not obstructed.
Knee airbags
Description of knee airbags
Applies to vehicles: wit h knee airbags
The knee airbag system can provide supple­
mental protection to properly restrained
front seat occupants.
Fig. 179 Driver 's knee airbag
The driver knee airbag is in the instrument
panel underneath the steering wheel
Q fig . 179, the knee airbag for the passenger
is at about the same height in the instrument
panel underneath the glove compartment .
The knee airbag offers additional protection
to the driver's and passenger's knees and up­
per and lower thigh areas and supplements
the protection provided by the safety belts.
If the front airbags deploy, the knee airbags
also deploy in frontal collisions when the de­ ployment threshold stored in the control unit
I),-

262 Tires and wheels
Tire service life
The service life of tires depends on a lot of
different things including proper installation
and balancing, correct tire pressure and driv­
ing style.
Fig. 212 Tire tread: tread wear ind icators (TWI)
_____ __,.J)
Fig. 213 Rotating t ires for more even wear
Tread Wear Indicator (TWI)
The origina l tires on your veh icle have
1/16 inch (1.6 mm) high "wear indicators"
¢
fig . 212 running across the tread. Depend­
ing on the make, there will be six to eight of
them evenly placed around the tire. Marks on
the tire sidewa ll (for example "TWI" or other
symbols) indicate the positions of the tread
wear ind icators . Worn tires must be replaced .
Different figures may apply in other countries
¢ & .
Tire pressure
Incorrect tire pressure causes premature wear
and can cause sudden t ire blow-out. For th is
reason, tire pressure must be checked at least
once a month
¢ page 258.
Driving style
Driving fast around curves, heavy acceleration
and hard braking increase tire wear.
Rotating tires for more even wear
For all four tires on your vehicle to have the
same service life, we recommend that the
front and rear tires are rotated according to
the tire manufacturer's suggested tire rota­
tion intervals. Please remember the follow­
ing:
- Tire rotation intervals may differ from the
vehicle service interva ls outlined in your
Ma intenance and Warranty Booklet .
- The longer one tire is used in one location
on the vehicle, the more it wears at certain
points; therefore, we recommend that you
follow the tire manufacturer's suggested
tire rotation intervals .
- Vehicles with front-wheel drive experience
more tread wear on the front wheels com­
pa red to all-wheel drive (quattro ®).
- Please rotate tires as shown¢
fig. 213.
-Extra care must be taken when rotating di-
rection-specific tires¢
page 279.
Wheel balancing
The wheels on new vehicles are balanced.
However, various situations during everyday
driving can cause them to become unbal­
anced, resulting in vibrations you can usually
feel through the steer ing wheel.
Unbalanced wheels must be rebalanced to
avoid excessive wear on steering, suspension
and tires. A wheel must also be rebalanced
when a new tire is installed.
Incorrect wheel alignment
Incorrect wheel alignment can cause exces ­
sive tire wear, impairing the safety of the vehi­
cle. If tires show excessive wear, have the
whee l alignment checked by an authorized
Audi dealer or qualif ied workshop.
All wheel drive
Vehicles with quattro ® must a lways have tires
of the same size, construction and tread type.
For details see
¢page 210. ..,.