brakes AUDI Q7 2013 Owner´s Manual

120 Adapti ve crui se control
_&. WARNING
-
Following other vehicles too closely in ­
creases the risk of a crash and serious per­
sonal injury .
- Following other vehicles too closely, par­
ticu larly at higher speeds increases the
risk of coll is ions and serious personal in­
jury.
- Setting short distances to the traffic
ahead reduces the time and distance
available to bring your vehicle to a safe
stop and makes it even more necessary
to pay close attention to traffic .
- Always select a speed and distance to
traffic ahead that is safe and appropriate
under the prevailing traff ic, road, weath­
er and lighting conditions.
- Never rely on the distance control fea­
ture of ACC a lone to prevent rear-end col­
lis ions. Always be prepared to b rake and
take evasive act io n to avoid co llisions
and other ac cident situations.
- Never allow the clos ing speed between
yo u a nd other vehicles to be so h igh that
the adaptive cruise control may not be
able to slow your vehicle safe ly . If clos­
ing speed is too high, yo u m ust app ly the
brakes yourself to reduce the risk of a
rear-end crash.
- Always select a greater following dis­
tance to the veh icle ahead on wet roads
than on dry roads.
- Always read and heed the information
and WARNINGS
¢ &. in Description on
page 113.
(D Tips
The distance setting is reset to the factory
default
DIS TANCE 3 the next time the ig­
nition is turned on.
Driver information
Displays in the instrument cluster
Applies to veh icles: w ith adaptive cruise contro l
Depending on the driving situation, driver in­
formation is displayed in the instrument clus ­
ter .
Fig . 1 34 Overview ins tr u me nt cluster
@ Speedometer and indica to r li ght d isp lay
@ Display in the instrument cluster
@ Speedometer and indi cato r light
display
Important information concerning vehicle op ­
eration with adaptive cruise control is shown
in display a rea @. The desired speed you set is
i ndica ted in the speedometer (L ED lights
aro und the edge).
T he ind icator lights show whether the system
has detected a vehicle trave ling ahead .
@ Display in the in strument cluster
In display area @ information from the navi­
gation system* and the tr ip computer is dis­
played in addition to informat ion about adap­
t ive cru ise control.
You can select among the different informa­
t io n by repeated brief taps on the
I RESET I but­
ton on the w indshie ld w iper lever
c::> page 25,
Operation .
Certain pieces of information in the bottom
part of the d isplay are not shown permanent­
ly . Information is displayed only if you set or
change the speed setting, change the time in­
te rva l, when messages are disp layed or if the
adaptive cruise contro l is turned off for safety
reasons .

Display in the speedometer
Applies to vehicles: with adaptive cruise control
Fig. 135 D isplay in the speedomete r
Des ired spe ed
The desired speed set by the driver is dis­
p layed by a red LED.
If the desi red speed was set between two
lines on the speedometer using the
I SETI but ­
ton, the two closest light emitting diodes will
come on <=>
fig. 135.
The system a llows only speeds to be set be ­
tween 20 to 95 mph (30 to 150 km/h) to be
set. This speed range is faint ly illuminated in
the speedometer (LED lights).
Ind icator light s (symbol s)
-- Open road :
The indicator light _
shows that ACC is active and that no moving
vehicle has been detected with in range of the radar sensor up ahead in your lane of
travel. The set speed is maintained.
- - Driving in tr aff ic: The indicator
light - shows that a vehicle moving in
your lane of travel has been detected up
front in your lane of travel. Your speed is ad­
justed according to the speed of the vehicle
up front . ACC accelerates and brakes auto­
matically within the system's capabilit ies .
-- Driver int erv ent ion prompt: The
red flashing warning light- means
Reque st for dri ver to assum e co ntr ol. You
as the dr iver must slow the vehicle with the
f oot brake. The symbol - tells you
t h at the adaptive cruise co ntrol is not able
to slow the vehicle down enough to keep a
enough distance to the vehicle in front of
you. A warning tone will also sound when
Ad apti ve crui se control 121
the symbol appears. For more information
about the driver intervention prompt
r::!) page 124.
_& WARNING
Improper use of the adaptive cruise con­
trol features and inattention can lead to a
crash and serious personal injury.
- Never allow the closing speed between
you and othe r vehicles to be so high that
the adaptive cruise contro l may not be
able to slow your vehicle safely. If clos­
ing speed is too high, you must apply the
brakes yo urself to reduce the risk of a
rear-end crash.
- Always select a greater following d is ­
tance to the vehicle up ahead on wet
roads than on dry roads.
- Always read and heed the information
and WARNINGS <=>
& in Description on
page 113 .
(D Tips
-If you use the accelerator to go faste r
t han t he speed of the vehicle ahead of
you, the dr iver intervention prompt will
not be accompan ied by a warn ing tone.
- If the speed you previously set is exceed­
ed, the indicator light in the speedome­
ter will switch off.
Display in the instrument cluster
Appl ies to vehicles: wit h adaptive cruise control
F ig. 136 D isp lay in the instrument cluster
-
Scroll through the available information dis­
plays by br iefly tapp ing the
I RESET ! button at
the end of the windshield wipe r lever. You can ..,.

the 20 to 95 mph (30 to 150 km/h) speed
range .
ACC: Unavailable
The text message ACC: Unavailable appears,
for example, if the temperature of the brakes
i s excessive. Adaptive cruise control is tempo­
rarily not available. A warning tone sounds as
a reminder .
ACC: Not available
The text message ACC: Not available appears
in the event of a malfuncti on. Adaptive cruise
control is turned
off . A warning tone sounds
as a reminder. Have the system inspected by a
q ua lified dealership.
ACC: Sensor blocked
The text message ACC: Sensor blocked ap­
pears when the ACC System can no longer ac­
curately detect vehicles moving up ahead in
your lane of travel. Adaptive cruise control is turned
off. A warning tone also sounds as a re­
minder.
To decide whether it is necessary to switch
off
the ACC (ACC : Sensor blocked) or if it is only a
temporary condition (ACC functionality limit­
ed) the system will take into cons ideration the
outside temperature and/or the windshield
operat ion.
The ACC sensor is dirty or blocked (e.g. leaves,
snow).
The ACC sensor is located behind the area to
the right of the front license plate . If the ACC
sensor is dirty or blocked, clean the area to re­
store system operat ion.
ACC off: Manual control!
The text message ACC off: Manual control!
appears after the ve hicle has been brought to
a standstill by the adaptive cruise control. In
this case you must depress the brake peda l to
prevent the veh icle from rolling. A warn ing
tone sounds as a reminder.
Adaptive cruise control 123
Stabilization control (ESC)
The text message Stabilization control (ESC)
appears if the Electronic Stabilization Control
(ESC) has intervened . In this case the adaptive
cruise control is automatically turned
off . This
is accompanied by a warn ing tone.
Speed
T he set speed in mph (Canada km/h) always
appears when saving or changing the speed in
adaptive cruise control
¢ page 116, How is
the speed stored?
and ~ page 117, Changing
stored speed.
ACC functionality limited
T he message ACC functionality limited ap­
pears when the ACC System does not detect
any moving vehicles up ahead in yo ur lane of
trave l for a longer period of time. During this
time, the distance to moving vehicles in your
lane of travel up ahead is not being ma in­
ta ined . The ACC system is not switched off,
and increased attention to the traffic situation
is absolutely necessary. The following may be
reasons why the message
ACC functionality
limited
appears :
- The ACC sensor is d irty . The ACC system is
not react ing, or is not reacting correctly, to
moving vehicles up ahead in your lane of
t ravel.
- There may be very light traffic on and there
is nothing that marks the side of the road
(for examp le, guard ra ils, traffic signs,
trees). As soon as a moving vehicle up ahead
is detected again, ACC becomes active again
and the message disappears.
T he ACC sensor is located be hind the area to
the right of the front license plate. If the ACC
senso r is dirty or blocked, clean the area to re­
store system operation.
Parking brake!
T he text message Parking brake! appears,
when the parking brake is applied. ACC is
turned
off . A warning tone sounds as a re ­
minder.

given to another person, the saved settings remain as they are .
System limitations
General information
Applies to vehicles: with adaptive cruise co ntrol
The radar sensor has limits that the driver
must know to be able to use ACC properly .
The adaptive cruise control works within lim­ its that are also related to radar sensor range
and sight distance . In some situations ACC
may react unusually or late from the driver's
point of v iew. Therefore, always be attent ive
to what is happening around you and always
be ready to intervene, if necessary:
-when driving around curves ¢page 125
- when vehicles up front are not in line with
your vehicle ¢ page 126
- when other veh icles are changing lanes
i=> page 126
- when other vehicles are difficult to detect i=>page 126
- when vehicles up ahead are not moving or obstacles are in your travel lane i=>page 126
A WARNING
The radar sensor's function and range can
be reduced by rain, snow and heavy spray.
Moving veh icles up ahead may not be
prompt ly detec ted or may not be detected
a t all.
- Always pay careful att ention to the traf­
fic s ituation and be ready to intervene
and be re ady to take comp lete cont rol
whenever necessary.
Ad apti ve crui se control 125
When driving around curves
App lies to vehicles: wit h adaptive cruise control
Fig. 139 Ve hicle e nter ing a curve
Fi g. 140 Ve hicle leav ing a curve
Entering a curv e
When entering a curve, the adaptive cruise
control may react to a vehicle in the next lane
and apply the brakes in your vehicle
¢ fig . 139. The braking action can be overrid·
den by depressing the accelerator pedal.
L e aving a curv e
At the end of very long curves, ACC's predic­
tive lane reading can cause ACC to react to an­
other vehicle in the next lane and app ly the
brakes on your vehicle¢ fig . 140. The braking
action can be overr idden by depress ing the ac­
ce lerator pedal.

Audi braking guard
Description
Applies to vehicles: with a daptive cruise co ntrol
Audi braking guard warns you of a possible
collision with a moving vehicle up ahead .
Fig. 146 Display in the instrument cluster
The Audi braking guard is active from a speed
of approx. 20 mph (30 km/h) and works with­
in the system limits¢
page 125 even when
the adaptive cruise contro l is deactivated.
A radar sensor is bu ilt into the front of the ve­
hicle
¢page 114, fig. 127. The system is in­
tended to measure the distance to reflective
surfaces .
If a measurement is not possible,
the system does not respond.
When the measurement has been taken, the
system can recognize a possibly hazardous sit ­
uation, for example, whe n a vehicle up ahead
in your lane of trave l sudden ly brakes or when
your own vehicle is moving at high speed to­
wards a much slower vehicle up ahead . As
soon as the system senses that a possible col­
lision with the vehicle up ahead can only be
avoided by immed iate full brake application or
by an avoidance maneuver, a warning appears.
The system has a defau lt response time to be
able to signal before a collision occurs. This
system response time is automat ica lly re­
duced if you acce lerate actively, fo r example
to join a highway. Braking, transverse acceler­
ation and the steering angle can lead to a re­
duced system response time. The warning is
deactivated if you begin to overtake with full
acceleration .
Adaptive cruise control 127
The system can make you aware o f two differ­
ent hazardous situations:
Distance
The distance warning is given if the system
calculates that there is not enough distance
to the vehicle up ahead a period of more than
S seconds . If the distance is less than 30 feet
(9 meters) at SO mph (80 km/h), for examp le,
an optical display comes on in the instrument
cluster¢
fig. 146.
If the vehicle ahead brakes sharp ly, Audi brak­
ing guard cannot help you to avoid a collision,
even in the case of an immediate response.
Take immed iate action to avoid the co llision
and increase the distance to the vehicle up
ahead.
Speed
If there is a much slower vehicle moving up
ahead in your lane, or if the vehicle ahead
brakes sharply, the Aud i brak ing guard calcu­
lates the po int from which a collision can only
be avoided by full braking or by an avoidance
maneuver. If a warning does sound, a poss ible
collision with the ve hicle in front can on ly be
avo ided through an evasive maneuver or by
braking.
The warning is given in two stages :
-Pre-warning: A visual display appears in the
instrument cluster and a warning tone
sounds.
- Acute warning: If you do not respond to the
pre-warn ing, the second stage warning is
given. A quick brake application helps to di­
rect your attention to the road and traffic
situation.
Under heavy braking, the brake ass istant
¢
page 114 also helps you benef it from maxi­
mum brak ing efficiency.
A WARNING
Inatt ention can cause collisions, other ac­
cidents and serious personal injuries.

128 Adapti ve crui se co ntrol
-Always pay close attenti on to t he traffic,
even w hen the Aud i brak ing guard is
switched on. The Aud i b rak ing guard pro­
vides a warning but does no t brake the
car for you . You m ust apply t he brakes
yours elf!
- Always ke ep the sa fe and legal distance
betwe en your vehicle and veh icles up
ahead.
-Audi braking guard works within limits and w ill not respond outs ide the system
limits, for examp le when approaching a
stopped vehicle or s tationary obstacle
(end of a traff ic jam or veh icle that has
broken down in traffic).
- Always remember th at the radar sensor
f or the A udi braking guard wo rks within
defined detection and range limits that
may prevent the proper detection of oth­
er veh icles.
- The radar sensor's function and range
can be reduced by rain, snow and heavy
spray. Moving vehicles up ahead may not
be promptly detected or may not be de­
tected at al l.
- Always pay careful attention to the traf­
fic s ituation and be ready to intervene
and be ready to take comp lete control
whenever necessary.
- Reflective surfaces includ ing crash barri­
ers or tunnel entrances may impair the
function of th e radar sensor .
Settings in the MMI
Applies to vehicles: with adaptive cruise control
The settings of the Audi braking guard are
performed in the MMI.
.. Se lect :
ICARI fu nct ion button> Systems *
control button > Audi braking guard . Or
.. Se lect:
I CARI funct ion button > Car sys­
tems *
control button > Driver assist > Audi
braking guard .
- System -
the Audi braking guard system can
be switched
On and Off .
-Early warning -the acoustic warning and
the messages can be switched
On and Off .
(D Tips
When handing ove r the keys to another
person, the p revious settings are adopted
i f the Audi braking g uard is activated
¢ page 43.
Driver's information in the instrument
cluster display
Applies to vehicles: with adaptive cruise contro l
Braking guard activated
Th is message appears when the Aud i b ra ki ng
guard applies the brakes du ring a second
st age (a cute) war ning .
Braking guard off
This message appears when the system has
been deac tivated via the MMI. This message
also appea rs br iefly at each beginn ing of a t rip
i f t he sys tem is swi tched off .
This message also appears when the system is not available because of a malfunct ion or if
E SC is switched to the Off road
mode ¢ page 225. The system can no longe r
war n of an impending coll is io n.

138 Automatic transmi ssion
co uld "creep" forward or backward.
When stopped, keep the brake pedal
fully depressed and use the parking brake if necessary to keep the vehicle
from ro lling .
- If the selector lever is unintentionally
moved into N wh ile you are driving, take
yo ur foot off the accele rato r pedal and
wa it for the engine to return to idle
speed befo re selecting a d rivi ng position .
- Never shift into "R" or "P" when the vehi­
cle is in mot ion.
- Never get out of the dr iver 's seat when
the engine is runn ing .
- If you must get out of the vehicle, move
the se lector lever securely into the P po­
sit io n and apply the par king brake f irm ly.
- If the eng ine must remain ru nning, never
hav e any driv ing pos ition engaged when
c hec king under the hood . M ake sure t he
sele ctor lever has securely eng aged and
is locke d in "P" with the par king brake
firmly set ¢
page 255, Engine compart ­
ment .
Otherw ise, any increase in eng ine
speed may set the vehicle in m otion,
even w ith the par kin g brake applied.
Selector lever positions
This section describes the selector lever posi ­
tions and driving ranges.
F ig. 158 Display in t he in st rum en t cluste r: selecto r
lev er in po sit ion P
The inst rumen t cluste r display shows the c ur­
rent selector lever position .
P - Park
In this selector lever posi tion the transm is­
s ion is mechanica lly locked. Engage
P only
whe n the vehicle is
completely stopped¢&.
in Driving the automatic transmission on
page 137.
T o shift in or out of posit ion P , you mus t first
press and ho ld the brake pedal and then press
the re lease button in the selector leve r hand le
whi le moving the selector lever to or from
P .
You can shift out of th is position only with the
ignition o n.
R • Reverse
The transm iss ion w ill automatically select the
lowest gear ratio when you shift into reverse .
Se lect
R o nly when t he vehi cle is at a full stop
and the engine is running at idle speed¢&. in
Driving the automatic transmission on
page 137.
B efore you move the se lector lever to R , press
both the button in the hand le o f the se lecto r
lever and the brake pedal at the same t ime.
W hen the ignition is on, the bac kup light s illu­
minate w hen t he selec to r l ever is
moved in to
R .
N -Neutral
The transm iss io n is in neut ral in this pos it ion .
S hi ft to t his position fo r standing with the
brakes app lied
¢ page 139.
When the vehicle is stat iona ry or at speeds
below 3 mph (5 km/h) , you must always app ly
t h e foo tbrake before and wh ile mov ing the
l ever o ut o f
N.
D - Normal position for driving forward
Position D is for no rma l city and highway driv ­
ing . It ranges from zero to top speed and all
gears shift automatically , depend ing on en­
gine load, d riving speed and a utomat ically se­
l ected shift p rog rams.
When the vehicle is stat iona ry or at speeds
below 3 mph (5 km/h), you must always app ly
IJ,,

226 Intellig ent technol ogy
The vehicle is then stabilized by the forces act­
ing on the whee l during braking. If the vehicle
is
oversteering (rear tends to sk id out of the
turn), the brakes are ma inly applied on the
wheel that is on the outside of the curve. In
the case of a vehicle that is
understeering
(tendency to slide out of the curve), the
brakes are applied as needed on the whee l
that is on the ins ide of the curve or addit ional­
l y on the o ther wheels. An acoustic s ignal indi­
cates when ESC b rake app lication cuts in
¢ A .
The system operates across the entire speed
range in combination with the ABS system
¢ page 229. If the Anti-Lock Brake System
(ABS) malfunctions, the ESC wi ll be out of ac­
tion as well .
Activating
When you turn on the engine, ESC w ill auto­
mat ica lly be act ivated and will perform a se lf­
test. As soon as the test is comp leted, the sys­
tem is in normal operating mode.
Offroad mod e
ESC should normally be ope rated in normal
mode because this ensures maximum vehicle
stability. If necessary, you can act ivate the
ESC offroad mode by pressing the but to n
¢ fig . 232 to obtain maximum traction and
braking ability when driving
off paved roads at
l ow speeds. In ESC offroad mode, the indica­
tor light
Ii) ill uminates and the message Sta ­
b ilization control (E S C): Offr oad . Wa rning !
R estric te d stabilit y
appears br iefly in the dis­
p lay .
The ESC offroad mode can be useful in the fo l­
low ing except ional situations when slip or a
h ighly effective differential locking function is
des irable . Examp les:
- when driving with tire chains,
- when driving in deep snow or on loose
ground,
- when driving on uneven surfaces with the
whee ls severe ly unloaded (articulation), and
- when rocking the vehicle loose after it has
become stuck . When the
unusual situation is past, you
sho uld shift back to the norma l ESC operating
mode by pushing the button again . The mes­
sage
S ta b ilizat ion cont rol (ES C): O n then ap­
pears briefly in the display.
H ill desc ent control
The hill descent control is switched on in ESC
offroad mode . When slowly descending steep
gradients on loose ground or when the axles
are articulated, hill descent control provides ass istance by automatically apply ing the
brakes to keep vehicle speed constant. The ve ­
hicle is also rendered easier to steer by selec­
t ive d istr ibut ion of braking force. Hill descent
control intervenes when:
- the acce lerator pedal is not pressed,
- the vehicle is travelling less than 12 mph
(20 km/h),
- a steep gradient is detected,
- wheel behavior indicates loose ground or
conditions with poor adhesion (e .g. also axle
art iculation).
Hill descent contro l operates both d riving for­
ward and in reverse. Active hill descent con­
tro l is deactivated by pressing the accelerator
pedal until the condit ions for activation al­
ready listed are met again .
A WARNING
--
- The Electronic Stabilization Contro l is
neverthe less s ubject to the laws of phys­
ics. It is part icularly important to pay at­
tention to this fact on wet and slippe ry
roads . It i s therefore important that you
always adapt your dr iving to the cond i­
tion of the road and traffic conditions . Do
not a llow the increased safety provided
by the E lectronic Stabilization Contro l
system to lull you into accepting addi­
tional safety risks .
- Please be aware that in ESC offroad
mode, particularly on a smooth and s lip­
pe ry road, the wheels may have an in­
creased tendency to sp in and the vehicle
may b reak away - dange r of skidding!
~

228 Intelligent technology
To ensure that the ASR works properly, all
four wheels must be fitted with identical
tires. Any differences in rolling rad ius of
the t ires can cause the system to reduce
engine power when this is not desired. See
also¢
page 291, New tires and replacing
tires and wheels.
Braking
General information
What affects braking efficiency?
Operating conditions and driving habits
The brakes on today's automob iles are st ill
subject to wea r, depending la rgely on operat­
ing cond itions and dr iv ing habits
Q ,& . On
vehicles that are either driven mostly in stop­
and -go city traffic or are driven hard, the
brake pads should be checked by your author­
ized Audi dealer more often than specified in
the
Warranty & Maintenance booklet . Failure
to have your brake pads inspected can result
in reduced brake performance .
On steep slopes, you shou ld use the braking
effect of the engine. This way, you prevent un­
necessary wear on the brake system. If you
must use your brakes, do not hold the brakes
down continuously . Pump the brakes at inter­
va ls.
Noises may occur when braking depending on
the speed, braking force and outside condi­
tions such as temperature and humidity.
Moisture or road salt
Under certain conditions, for examp le, when
driving through water or very heavy rain, or
even after washing your vehicle, the braking
effect can be reduced due to moisture (or in
freezing conditions ice) on the brake pads. A
few careful brake applications should dry off
the brake pads o r remove any ice coatings.
When you are driving at higher speeds with
the w indshield wipers on, the brake pads will
brief ly touch the brake discs in regular inter- vals so as
to improve reaction time when brak ­
ing on wet surfaces . You, the driver, will not
notice anything.
T he effect iveness of the brakes can be reduced
when the vehicle is driven on a sa lt-covered
road and the brakes are not used . Here too,
you should clean off accumulated sa lt coating
from brake discs and pads w ith a few careful
applications of the brake¢,&.
Corrosion
There may be a tendency for dirt to build up
on the brake pads and corrosion to form on
the discs if the car is not driven regu larly or
only for short trips with litt le use of the
brakes.
If the brakes are not used frequently, or if cor­
rosion has formed on the discs, it is advisable
to clean off the pads and discs by braking
firmly a few times from a moderately high
speed
c> ,& .
Faults in the brake system
If you shou ld notice a sudden increase in
brake pedal trave l, then one of the two brake
c ir cuits may have fa iled
c> ,& .
Low brake fluid level
Malfunctions can occur in the brake system if
the brake fluid level is too low. The brake fluid
l evel is monitored electronically .
Brake lining wear status
Brake lining wear may be checked by visual in­
spect ion of the condition of the brake pads
through the openings in the wheel. If neces­
sary, the wheel may be removed for this in­
spect ion
c> page 304, Changing a wheel.
A WARNING
-- You shou ld perform braking maneuvers
for the purpose of cleaning the brake
system only if road conditions permit.
Othe r road users must not be put at risk -
you may cause an accident!

-Before descending a steep grade, reduce
speed and shift transmiss ion into a lower
gear or lower driving range. Do not ride
the brakes or hold the pedal down too
long or too often. This could cause the
brakes to get hot and dimin ish braking
efficiency.
- Do not "r ide the brakes" by resting your
foot on the pedal when you do not intend
to brake. Th is may cause the brakes to
overheat, prema ture wear and increased
stopping distance .
- Under certain climat ic and operating
condit ions such as passing through wa­
ter, driving in heavy rain or after washing
the vehicle, the effectiveness of the
brakes can be reduced . In winter, ice can
accumulate on the brake pads, linings,
discs and drums. Carefully apply brakes
for a test . Brakes will dry and ice coat­
ings will be cleaned off after a few care­
ful brake applications.
- Driv ing for an extended period of time on
salt-covered roads w ithout us ing your
brakes can also affect braking efficiency .
Clean off accumulated salt coating from
brake discs and pads w ith a few caref ul
brake applicat ions.
- If you damage the front spoiler, or if you
install a different spoiler, be sure the air
flow to the front brakes is not obstruct ­
ed. Otherwise the brake system could
overheat reducing the effectiveness of
the entire brake system.
- Failure of one brake circuit will impair
the braking capability resulting in an in­
creased stopp ing distance. Avoid driv ing
the vehicle and have it towed to the near­
est author ized Audi dealer or qualified
workshop .
Brake booster
The brake booster adds extra braking power.
The brake booster works with vacuum pres­
sure which is created only when the engine is
running¢ &,.
Int ellig ent technolog y 229
A WARNING
-Never let the veh icle roll to a stop with
the engine shut off .
- If the brake booster is not working, for
example when towing your vehicle, or because the brake booster has somehow
been damaged, the brake pedal must be
pressed considerably harder to make up
for the lack of booster assistance .
Functioning of Anti-Lock Brake System
(ABS)
ABS prevents the wheels from locking up un­
der braking.
T he ABS contributes effect ively to vehicle con­
trol s ince it preve nts the whee ls from
locking
when the brakes are applied. This means that
the vehicle remains steerable and is less likely
to skid .
With ABS y ou do not n eed to pump the
bra ke. Just h old t he br ake ped al d own .
However, do not expect the ABS to shorten
braking distance under
all circumstances.
When dr iving on g ravel or on new ly fallen
snow o n top of icy s urfaces, braking dis tance
may be even longer, therefore, under these
circumstances, it is especia lly important that
you drive s low ly and with great care.
How the ABS s ystem works
An a utomat ic check is made when a speed of
about 12 mph (20 km/h) is reached . When
th is happens, a pumping noise can be heard.
If an ind iv idual whee l begi ns to rotate too
s low ly in relation to vehicle speed and tends
to lock, the ABS automatically reduces brake
pressure to prevent that whee l from locking .
T his automatic adjustment p rocess will cause
a
sli ght vibrati on of the brake pedal and some
noises to a le rt you that ve hicle speed m ust be
adapted to existing road and traffic condi ­
tions. •
•