traction control AUDI S4 2015 Owners Manual

@ Tips
Your vehicle may be equipped with Audi
connect. Your use of certain Aud i connect
features req uires wireless serv ices that are
provided by a third party wireless telecom­
municat ions provider. For details regard­
ing how information obtained through
Aud i connect is collected, processed,
transmitted, used, and shared, please see
your contra ct w ith the wire less telecom ­
municat ions provider and the "About A udi
connect" tab in your vehicle's MMI*:
!MENU ! button> Audi connect > About
Audi con nect .
Electronic Stabilization
Control (ESC)
Description
ESC helps to improve road holding and vehicle
dynamics to help reduce the probability of
skidd ing and loss of veh icle control. It works
only when the eng ine is running. ESC detects
certain difficult driv ing situations, including
when the vehicle is beginning to spin (yaw) out of cont ro l and he lps you to get the vehicle
back under control by select ively b rak ing the
wheels, and/or red ucing engine powe r and
p roviding steering assistance to help hold the
ve hicle on the driver's intended course . The in­
dicator light
DJ in the instrument cluster
blinks when ESC is taking action to help you
control the vehicle.
ESC has limitations.
It is important to remem­
ber that ESC cannot overcome the laws of
phys ics. It will not a lways be able to help out
under all conditions you may come up against.
For example, ESC may not always be able to
h elp you master situat ions where there is a
sudden change in the coefficient of fr iction of
the road surface. When there is a sect io n of
d ry road that is s udden ly cove red with water,
slush o r snow, ESC canno t perform the same
way it would on the dry su rface.
If the vehicle
hydroplanes (rides on a c ush ion of wate r in­
stead of the road surface), ESC wi ll not be
ab le to he lp you steer the veh icle because con-
Int ellig ent technolog y 185
tact with the pavement has been interrupted
and the vehicle cannot be braked or steered .
D uring fast corner ing, particular ly on wind ing
roads, ESC cannot always deal as effectively
with difficult dr iv ing s ituations than at lower
speeds. When towing a trailer, ESC is not able
to help you regain control as it would if you
were not tow ing a trailer.
Always adjust your speed and driving style to road, traffic and weather conditions . ESC can­
not override the vehicle's physical lim its, in­
crease the availab le tract ion, or keep a veh icle
o n the road if road departu re is a result of
driver ina ttent io n. Instead , ESC imp roves the
poss ibility of keep ing t he vehicle under con­
trol and on the road during extreme maneu­
vers by using the driver's steering i nputs to
help keep the vehicle go ing in the intended di­
rect ion. If you are traveling at a speed that
causes you to run off the road before ESC can
provide any assistance, you may not experi­
ence the benefits of ESC.
ESC is switched on all the time. In certain sit­
uat ions when you need less traction, you can
switch off ASR by pressing the butto n
[ill
~ page 187, fig. 174 or~ page 187,
fig. 175. Be sure to sw itch ASR on aga in when
you no lo nger need less traction.
The following systems are integrated in the
ESC:
Anti-lock bra king sy stem (ABS )
ABS prevents the whee ls from locking up
when brak ing. T he vehicle can st ill be steered
even dur ing hard braking. App ly steady pres­
su re to the brake peda l. Do not pump the ped­
al. A pulsing in the brake pedal ind icates that
the system is helping you to brake the veh icle .
Brake assi st system
The brake ass ist system can decrease braking
distance. It increases brak ing power when the
drive r presses the brake peda l quickly in emer­
gency s ituations. You must press and hold the
brake pedal unti l the s ituation is over. In
vehicles wi th adap tive c rui se control*, the
brake assis t system is more sensitive if the
•
•

"" N
0 ::.,: co ,...., \!) 1.1'1 ,...., 1.1'1 ,....,
The all-wheel drive concept is designed fo r
high engine power. Your vehicle is exception ­
ally powerful and has exce llent dr iving charac­
ter istics both under normal driving conditions
and on snow and ice . Always read and follow
safety precautions
c> & .
Winte r tir es
When driving in the winter, your ve hicle with
all-wheel drive has an advantage, even with
regular t ires. In winter road conditions it may
be adv isable to mount winter tires (or all-sea­
son t ires) for imp roved driveability and brak­
ing: these tires must be mounted on
a ll four
w heel s.
See also c> page 254, Winter tires.
Tire chain s
Where tire cha ins are mandatory on certain
roads, th is normally also applies to vehicles
with all-wheel drive
c> page 255, Snow
chains.
R eplacing wheel s/tire s
Vehicles with all-wheel drive must a lways
have tires of the same size. Also avoid t ires
with d ifferent tread depths . For details see
page ~
page 248, New tires and replacing
tires and wheels.
Off-Ro ad dri ving ?
Your Audi does not have enough ground clear­
ance to be used as an off-road veh icle. It is
therefore best to avoid rough tracks and un­
even terrain as much as possible . Also refer to
c> page 193.
A WARNING
Always adjust your driving to road and traf­
fic condit ions . Do not let the ext ra safety
afforded by all-wheel drive tempt you into
taking extra risks .
- Although the all-whee l dr ive is very ef­
fective, a lways remember that b raking
capacity is limited by tire traction. Yo u
sho uld therefore not drive at excessive
speeds on icy or slippery road surfaces.
- On wet road surfaces, be careful not to
drive too fast because the front wheels
Int ellig ent technolog y 191
could begin to slide on top of the water
(aquaplaning). If th is should occur, you
will have no warning from a sudden in­ crease in engine speed as w ith a front­
wheel drive veh icle . Always drive at
speeds which are su ited to the road con­
ditions - risk of crash.
Energy management
Starting ability is optimized
Energy management controls the distribution
of electrical energy and thus optimizes the
availability of electrical energy for starting the engine.
If a vehicle with a conventiona l energy system
is not driven for a long period of time, the bat­
tery is discharged by idling current consumers (e .g. immobilizer). In certain circumstances it
can resu lt in there being insuffic ient energy
available to start the eng ine .
Intelligent energy management in your vehi­
cle handles the distribution of e lectr ica l ener­
gy. Start ing ability is markedly improved and
the life of the battery is extended .
Basically, energy management consists of
battery diagnosis , idling current manage­
ment
and dynamic ene rgy management .
Batte ry diagnos is
Battery diagnosis continuously determines
the state of the battery . Sensors determine
battery voltage, battery current and battery
temperature. This determines the current
state of charge and the power of the battery.
Idling current management
Idling current management reduces energy
consumption while the vehicle is standing.
With the ign ition switched off, it controls the
energy supply to the various electrical compo­
nents. Data from battery diagnos is is cons id­
ered .
Depend ing on the battery's state of charge,
individual consumers are gradually turned
off .,_ •
•

254 Tires and wheels
@ For the sake of the environment
Dispo se of old tires in accord­
ance with the local require­
ments.
Uniform tire quality grading
- Tread wear
- T raction AA A B C
- T empera ture ABC
Quality grades can be found where applicable
on the tire side wa ll between tread shou lder
and max imum sect ion width
¢ page 248,
fig. 193.
For example: Tread wear 200, Tract ion AA ,
Temperature A.
All passenger car tires must conform to Feder­
al Safety Requirements in addition to these
grades.
Tread wear
The tread wear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a spec ified
government test course .
For example, a t ire graded 150 would wear
one and one half (1 1/2) t imes as well on the
government course as a tire graded 100.
The relat ive performance of t ires depends
upon the actua l conditions of their use, how­
ever, and may depart significantly from the norm due to var iations in dr iving habits, serv­
ice practices and differences in road character­
istics and climate .
Traction
The traction grades, from highest to lowest,
are AA, A, Band
C. Those grades represent the
tire's abil ity to stop on wet pavement as
measured under controlled cond it ions on
specified government test surfaces of asphalt
and concrete . A tire marked C may have poor
trac tion performance ¢&,. .
Temperature
The temperature grades are A (the highest),
B, and C, representing the tire's resistance to
the generation of heat and its ability to dissi­
pate heat when tested under controlled condi­
tions on a specified indoor laboratory test
wheel.
Sustained high temperature can cause the
material of the tire to degenerate and red uce
tire life, and excessive temperature can lead
to sudden tire failure
¢ &,..
The grade C corresponds to a level of perform ­
ance which all passenger car tires must meet
under the Federal Motor Vehicle Safety Stand­
ard No. 109. Grades Band A represent higher
levels of performance on the laboratory test
wheel than the minimum required by law .
A WARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning or peak traction
characteristics.
A WARNING
The temperature grade for this tire is es ­
tablished for a tire that is properly inflated
and not overloaded. Excessive speed, un­
derinflation, or excessive load ing, either
separately or in combination, can cause
heat buildup and possible tire failure.
Winter tires -
Winter tires can improve vehicle handling on
snow and ice . At temperatures below 45 °F
(7 °C) we recommend changing to winter
tires .
In some heavy snow areas, local governments
may require true winter or "snow" tir es, those
with very deeply cut tread . These tires should
only be used in pairs and be installed on all
four wheels. Make sure you purchase snow
tires that are the same size and construction
type as the other tires on your vehicle. .,.