2015 AUDI S3 SEDAN park assist

Table of contents
Owner's Literature
About this Owner's Manual ... .. .
Cockpi t ... ...... ........... .. .. .. .
Cockpi t overview .......... .. .. .. .
Controls at a g lance . ..... ... .. .. .. .. .
Instrument s and indicator lights
Instruments .. .. ........... .. .. .. .. .
I ndicator ligh ts .... ..... ... .. .. .. .. .
On-Board Diagnostic system (OBD) ..... .
Driver inform ation system ..... .
Overview ..... .. ... .. ..... ... .. .. .. .
Operation . ..... .. . .. ..... ... .. .. .. .
Boost indicator .... ........... .. .. .. .
Efficiency program ............ .. .. .. .
Lap t imer a nd engine oil temperature
i n dicator . .. .... .......... ...... ... .
Start and drive .............. .. .. .
Opening and clo sing ...... .. .. .. .
Centra l locking .. .............. ... .. .
L uggage compa rtment lid .. .. .. .. .. .. .
Ch ild safety loc k ... ......... .. .. .. .. .
P ower windows . ............. .. .. .. .
P anorama s unroof .. ..... ... .. .. .. .. .
5
6
8
8
8
10
10
13
25
27
27
28
29
29
30
33
33
33
39
4 0
40
42
Light and Vi sion . . . . . . . . . . . . . . . . . . 43
Exterior lighting . . . . . . . . . . . . . . . . . . . . . 4 3
Interior lighting . . . . . . . . . . . . . . . . . . . . . 46
V1s1on . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 7
W indshield wipers . . . . . . . . . . . . . . . . . . . 49
Dig ita l compass . . . . . . . . . . . . . . . . . . . . .
51
Seats and storage ....... .. .. ... . .
General information .......... .. .. .. .
53
53
Front seats . . . . . . . . . . . . . . . . . . . . . . . . . 54
H ead rest raints . . . . . . . . . . . . . . . . . . . . . 56
Socket . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
S to rag e . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
L uggage compa rtmen t . . . . . . . . . . . . . . . 59
Roof rac k . . . . . . . . . . . . . . . . . . . . . . . . . .
6 2
Warm and cold . . . . . . . . . . . . . . . . . . . 64
Climate con trol sy stem . . . . . . . . . . . . . . . 6 4
2
Driving . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
General information . . . . . . . . . . . . . . . . . 70
Econom ica l and envi ronmentally-friendly
driving . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Steering . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Starting and stopp ing the engine
(ve hicles w ith an ign ition lock) . . . . . . . . . 73
Start ing and stopp ing the engine
(ve hicl es w ith a convenience key) . . . . . . . 75
Drive r messages . . . . . . . . . . . . . . . . . . . . . 7 7
E lectromechanica l pa rking brake . . . . . . . 78
Hill ho ld . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Automatic tran smission . . . . . . . . . 82
S troni c . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2
Trailer mode . . . . . . . . . . . . . . . . . . . . . . 91
Driving with a trailer . . . . . . . . . . . . . . . . . 91
Trai ler mode notes . . . . . . . . . . . . . . . . . . . 92
Driver assi stance . . . . . . . . . . . . . . . . . 9 4
Assi st .. .. .. .... .. .. ... .. ..... ... .. 94
E lectronic speed limiter* . . . . . . . . . . . . . . 94
Speed warning system . . . . . . . . . . . . . . . . 94
Cruise contro l system . . . . . . . . . . . . . . . . 94
Audi adaptive cruise control . . . . . . . . . . .
96
Audi pre sense . . . . . . . . . . . . . . . . . . . . . . 103
General informa tion . . . . . . . . . . . . . . . . . 103
Audi pr e sense bas ic . . . . . . . . . . . . . . . . . . 103
Audi pre se nse front. . . . . . . . . . . . . . . . . . 10 4
Driver messages . . . . . . . . . . . . . . . . . . . . . 106
Audi active lane assist . . . . . . . . . . . . . . . . 106
Audi s ide ass ist . . . . . . . . . . . . . . . . . . . . . 109
A udi drive select (d rive settings) . . . . . . . . 112
Parking systems
General information
Rear par king system
115
115
116
Parking system pl us. .. ........... .. .. 116
Rearv iew camera . . . . . . . . . . . . . . . . . . . . 117

M N
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..,.,
..,., ......
CD
@
®
©
®
®
(J)
®
Power windows
Door hand le
Aud i side assist
........ .... .. .
Centra l locking switch ... .. .. .. .
Powe r exter ior mir ro r adjustment
H ead light cont rol swit ch .. .. .. .
Vents
L ever fo r:
- Turn si gnals and high beams . . .
- Audi act ive lane assis t ... .. .. .
® Steer ing whee l w ith horn and
@
©
@
- Driver's airbag ....... .. .. .. .
- On-board computer controls .. .
- MMI, telephone , nav igat ion and
vo ice recogn ition system controls
- tiptron ic shift paddles (automatic
transmission)
I ns trumen t clus te r ..... .. .. .. .
W indshield washer system lever .
Steer ing column with:
- Ignit ion emergency operation (in
vehicles with conve nience key) .
- Ignit ion loc k (in vehicles wi th me-
chanical key) . ..... ... .. .. .. .
@ Adjustable steer ing column
(B) D epending on equipment: 4
0
109
37
47
4 3
64
45
106
152 28
87
1 0
49
7 7
73
72
- Cruise contro l lever . . . . . . . . . . 94
- adaptive cruise cont ro l . .. .. .. .
Driver's knee a irbag .... .. .. .. .
I ns trumen t illum ination . .. .. .. .
Hood re lease
. .. .... ... .. .. .. .
Luggage compartment release ..
C hild safety loc k bu tton . .. .. .. .
MMI disp lay (navigation, radio, TV/
video)
Glove compartment ( lockable) .. .
F ront passenger's airbag . ... .. .
Treble speakers Fr ont passenger's knee airbag .. .
Depending on equipment, b uttons
f or:
- Audi dr ive select ...... .. .. .. .
- Pa rking aid plus (o r with rearview
camera) 9
6
164
4 7
199
39
40
58
152
164
1 12
1 16
Co ckpit over view
-Eme rgency flashers ..... ... . .
- Elect ron ic St abiliza tion Control
( E SC) ..... .. .. .... .... ... . .
- MMI Displ ay
- Airbag Off indicato r ..... .... .
@ Depending on eq uipment:
- Manual climate contro l system .
- Automatic climate control
system ... .. ............. . .
@ Socket . .... .. .. ........... . .
S tronic se lector lever
. .... ... ..
Cup ho lde r .. .. .......... .... .
MM I On/ Off button
MMI control panel
Parking bra ke
@) I S TAR T ENGI NE STOPI button
(vehicles with convenie nce key)
(J} Tips
- Some the eq uipment listed here is only in­
sta lled in certa in models or is available as
an option . 44
123
160
6S
66
5 7
82
58
78
75
- Ope rat ion of the Multi Med ia In terface
(MMI) is described in a separate o perating
instructions manual. You can a lso find infor­
mation on A udi connect there.
9

....,
N
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rl I.O
"'
"'
"'
rl
@ Tips
Diesel engines: Due to the high efficiency of
these engines, the engine may not a lways
reach operating temperature in cold outside
temperatures. This is normal and not a cause
for concern.
Indicator lights
Description
Fig. 6 Instrument cl uster : example of a d isplay in vehicles
wit h a mo noc hro me display
@ Indicator light
® Message
© Status line:
-• ID Central indicator light or addition­
al d isplays for active systems such as
- - (USA models)
I. (Canada models)
electromechanical parking brake
- [ij;(i)~14 (USA models) / Iii (Canada models)
cruise control system*
- • I. Active lane assist*
The indicator lights in the instrument cluster
blink or turn on. They indicate functions or mal­
functions.
The
central indicator light@ • or a also
turns on with some indicator lights@.
I f the centra l indicator light @turns on, check
the additiona l information in the instrument
cluster display @ and @.
In addition to the indicator lights in the display,
there are add it ional ind icators in the tachometer .
They blink or turn on to ind icate functions or mal­
functions. Messages @ may also appear briefly
Instruments and indicator lights
with some indicato r lights. A warning tone a lso
sounds at the same time.
If t here are mult iple malfunctions, the indicator
lights will appear br iefly one after another in the
display.
T he ind icators and messages in the display can be
covered over by other displays . In cases where
the indicator light @is covered over, the centra l
indicator light@will remain visible until the
malfunction is repaired .
T he messages can be displayed again in the driv­
er information system
~ page 28, Operation.
Overview
Some indicator lights turn on briefly to check the
function of that system when you switch the igni­
tion on . These systems are marked with a./ in
the following tables. If one of these indicator lights does not turn on, there is a malfunction in
that system .
Your vehicle has either a monochrome display or a multicolored display, depending on vehicle
equipment . In a monochrome display, the indica­
tor lights @ only appear in white
Q page 13,
fig . 6. The central indicator light ©. / D also
appea rs to indicate the prio rity of these indicator
lights. Refer to the explanations for red or yellow
indicator lights.
Examples of indicator lights in a monochrome
display:
11 @ Priority 1 (high priority)
. © Refer to
red indicator lights
m@ Pr iority 2 (medium priority)
II ©
Refer to yellow indicator lights
D@ Pr iority 3 (low priority)
These are i nformative indicator
-- © lights
13

Instruments and indicator lights
Drive to your authorized Audi dea le r or a uthor ­
ized Audi Service Facility immediate ly to have the
malfunct ion corrected
¢ .&. .
1111 (USA m od els) /. (C an ada mod els) Park­
ing brake sy stem f ault! See owner' s manual
- If the indicato r light and the message appear
wh en th e vehi cle is stationar y or aft er swit ch­
ing the ignit ion on ,
check if you can release the
parking b rake . If you cannot re lease the parking
brake, see your authorized A udi dealer or au­
thorized Audi Service Facility. If you can re lease
the parking brake and the message st ill ap­
pears, see an authori zed Audi dealer or author­
ized Audi Serv ice Facility immediately to have
the malfunct ion corrected .
- If the indica tor light and message appear
whil e
driving ,
the hill start assist or emergency brak ­
i ng function may be malfunct ion ing . It may not
be possib le to set the pa rking brake o r release
i t once it has been set. Do not pa rk your ve hicle
o n hill s and see an authorized Audi dea ler or
authorized Audi Service Fac ility for assistance .
If the
1111 and El warning lights turn on to­
gethe r, take you r veh icle to a n author ized Audi
dealer o r autho rized Aud i Service Faci lity immedi­
ately to have the b rake pads inspected
¢ page 21 .
There is a lso a war ning tone when the lights t urn
on .
_& WARNING
- Read and fo llow ing the warn ings in
¢ page 198, Working in the engine com­
partment
before opening the hood and
check ing the brake fluid level.
- If the brake system indicator light does not
turn off or it turns on wh ile driving, the
brake flu id leve l in the reservo ir is too low,
and this increases the r isk of an accident.
Stop the vehicle and do not continue dr iv­
ing . See an author ized Audi dealer or au­
tho rized Aud i Service Fac ility for assistance.
- If the brake system indicator light tu rns on
together with the ABS and ESC ind icator
lights, the ABS/ ESC regu lating fu nction may
be malfunctioning. Functions th at stabilize
18
the vehicle are no longer ava ilable . This
could cause the rear of the vehicle to
swerve, which increases the r isk that the ve­
hicle will slide. Drive carefully to the nearest
author ized Audi dealer or authorized Audi
Service Fac ility and have the malfunction
corrected.
PARK/(®)/ ~ Electromechanical parking
brake
If the -(U SA mode ls) /. (Canada mode ls)
indicato r light turns on, t he parking brake was
set.
- (USA model s) / . (Canad a model s) Cau­
tion: Vehicle parked too steep
If the indicato r ligh t blink s and the message ap­
pe ars, there is no t eno ugh braking powe r to se ­
cu re the vehicle. The brakes have overheated. The
vehicle could ro ll away even on a sma ll incline.
- (USA mod els ) /. (Canada model s)
Plea se pr ess brak e pedal t o rel ease parking
br ake
To re lease the park ing brake, press the brake ped­
al and p ress the~ button at the same time, o r
star t driving with hill start assist
¢page 80,
Starting from a stop.
Ill Parking brak e!
There is a malfunc tion in the parking brake. Drive
to an authorized Aud i dea ler or authorized Audi
Service Facility immed iately to have the malfunc­
tion co rrected .
Ill Parking brake: limited functionality !
There is a malfunction in the parking brake. Drive
to an authorized Audi dea ler or a uthori zed Audi
Service Facility immed iate ly to have the ma lfunc­
tion correc ted.
!~;1 ;1J: );J;13~ ( USA models ) / ¢@'A Plea se relea se parking brake .
Release the par king brake if this message ap ­
pears.
lt1 ;1J :);tJ :H ( USA m odels ) / iiJ (Canada models)
Parking brake aut o release unavailable
...

M N
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1.1'1
1.1'1
,....,
If th is message appea rs, press t he b rake pe da l
f ir st and the n re lease the par king brake .
IZ,;11:);MJ~ (USA models) / [i] (Canada models)
Caution: Vehicle parked too steep
I f the indicator lig ht blinks and t he messag e ap­
pea rs, there is no t enoug h bra kin g power to se­
cure the vehicle. The b rakes have ove rhe ate d. T he
ve hicl e c ould r oll aw ay even on a sm all incli ne.
l:(;1;1:t:);MJ~ (USA models ) / [i] (Canada models)
Parking brake is applied
I f th is message appears , press t he brake pedal
f ir st and the n re lease the par king b rake if neces ­
sa ry .
(D Tips
For addit io nal information o n the park ing
b ra ke, re fe r to ¢
page 78.
_L Cooling system
• Switch off engine and check coolant level!
The coolant leve l is too low or the coolant tem­
pe ra tu re is too hig h.
Do not cont inue driving and switc h the engine
off. C hec k the coolant leve l¢
page 205.
- If the coolant leve l is too low, add coolant
¢ page 206 . Only cont inue driv ing once t he in­
dicator light turns off.
- If the coolant is at the correct level , the prob­
l em may be ca used by a ma lf u nction in the radi­
ator fan. Do not cont inue driv ing. See an au­
t h orized Aud i dea le r or authorized Audi Service
Fac ility for assistance .
• Coolant temperature too high! Let engine
run with vehicle stationary
L e t th e en gine cool by r unnin g it in idle for a few
minutes .
A WARNING
-Never open t he hoo d if you ca n see o r hear
steam o r co olant escap ing from the engine
compartment. T his i ncreases the ris k of
bur ns. Wai t until yo u no lo nger see o r hear
steam o r co olan t escap ing .
Instruments and indicator lights
-The engine compa rtment in any vehicle ca n
be a dange ro us area . Sto p the engine and a l­
low it t o cool befo re working in the engine
compa rtment. Always follow the informa­
tion fo u nd in ¢
page 198, Working in the
e ngine compartment .
(D Note
Do not cont inue dr iv ing if the . indicato r
li g ht tur ns on -this inc reases the r isk o f en­
g in e damage.
"1::::7: Engine oil pressure
• Switch off engine! Oil pres sure too low
St op t he engine and do not cont inue drivi ng .
Ch eck the eng ine oi l level
¢ page 203.
- If the engine o il level is too low, add eng ine oi l
¢ page 201 . Only continue dr iving once the in­
dicator light turns off.
- If the engine o il level is co rrect and the indica­
to r li ght still turns on, turn t he e ngine off and
do not cont inue drivi ng. See an authorized Aud i
dea le r or a uth o rized Aud i Serv ice Facility fo r as­
sis tance .
(D Tips
The oil pressu re war ning is not an oi l level i n­
dicator . Always chec k the o il l ev el re gular ly .
0 Alternator/battery
• Alternator fault : battery is not being charg­
ed
T he re is a malfunction in the al ternator or the ve ­
hicle e lectr ica l system .
Drive to an authorized A udi dealer or autho rized
Audi Serv ice Facility immed iately. Because t he ve­
hicle battery is d ra ining, turn off all unnecessary
elect rical e quipment suc h as th e MMI. Seek pro­
fe ssional ass istance if t he battery charge lev el is
too low.
(•) Low battery charge: Battery will be charged
while driving
The starting ab ility may be impaired.
19

M N
0 > co ,...., \!) 1.1'1
1.1'1
1.1'1
,....,
brake provides various convenience and safety
functions.
When starting from rest
- The integral hill start assist helps you when
driving by automatically releasing the parking
brake ¢
page 80 , Starting from a stop.
- When starting on inclines, the hill start assist
prevents the vehicle from unintentionally roll ­
ing back. The braking force of the parking brake
is not r eleased until sufficient driving forc e has
b ee n built up at the wh eels.
Emergency brake function
An emergency braking functions ensures that the
vehicle can be slowed down even if the
normal
brakes fail¢ page 80, Emergency braking func­
tion.
A WARNING
- Do not press the accelerator pedal inadver­
tently if the vehicle is stationary but the en­ gine is running and a gear is selected . Other­
wise the vehicle will start to move immedi ­
ately and could result in a crash.
-If the power supply fails, the released park­
ing brake can no longer engage. In this case,
park the vehicle on level ground and secure
it by placing the selector lever in the P posi­
tion. See an authorized Audi dealer or au­
thorized Audi Service Facility for assistance.
(D Note
If the . or 1111 (USA models)/ . (Canada
models) indicator light in the instrument clus­
ter blinks , there is a malfunction in the brake
system. Refer to the detailed description of
the indicator lights¢
page 17.
-If the - (USA models)/ . (Cana-
da models) or
Ill indicator light turns on,
there is a malfunction in the parking brake
¢ page 18.
(D Tips
-If the parking brake is set while the ignition
is switched
off, thP l<@) indicator light in the
button and in the instrument cluster dis­
play - (USA models) /. (Canada mod-
Driving
els) will turn off after a certain amount of
time.
- If driver's door is opened while the ignition
is switched on, the parking brake sets auto­
matically. This prevents unintended rolling
of the vehicle.
- Occasional noises when the parking brake is
applied and released are normal and are not
a cause for concern.
- When the vehicle is parked, the parking
brake goes through a self-test cycle at regu­
lar intervals. Any noises associated with this
are normal.
- If there is a power failure, the parking brake will not set if it is released, and it will not
release if it is set¢&. See an authorized
Audi dealer or authorized Audi Service Fa­
cility for assistance .
Parking
.. Press the brake pedal to stop the vehicle.
.. Pull the switch@¢
page 78, fig . 71 to set the
parking brake.
.. Place the selector lever in the P position.
.. Turn th e engine off¢,& .
.. Turn the steering wheel when pa rking on in­
clines so that the wheels will roll into the curb
if the vehicle starts moving .
A WARNING
--Always take the vehicle key with you when
leaving the vehicle, even for a short period
of time. This applies particularly when chil­
dren remain in the vehicle. Otherwise the
children could start the engine , release the
parking brake or operate electrical equip­
ment (e.g. power windows). There is the risk
of an accident.
- When the vehicle is locked, no one -particu­
larly not children should remain in the vehi­
cle. Locked doors make it more difficult for
emergency workers to get into the vehicle,
which puts lives at risk.
79

Driving
Starting from a stop
The start assist function ensures that the park­
ing brake is released automatically upon start­
ing.
Stopp ing and appl ying parking br ake
.,. Pu ll the switch @q page 78, fig. 71 to set the
parking brake.
Starting and aut omatically rel ea sing the
pa rking br ake
Requirement: The driver 's door must be closed.
.,. When you press the accelerato r pedal, the park­
ing brake is automatically released and your ve ­
hicle begins to move.
When stopp ing at a traffic signa l o r stopp ing in
city traffic, the parking brake can be applied . The
vehicle does not have to be held with the brake
pedal. The parking brake e liminates the tendency
to creep when a selector lever position is engag­
ed. As soon as you press the accelerator pedal,
the park ing brake releases automatically and the
veh icle starts to move.
St arting on slope s
When starting on inclines, the h ill start ass ist
prevents the vehicle from unintentionally rolling
back . The braking force of the parking brake is
not released unt il sufficient d riving force has
been b uilt up at the whee ls .
(0 Tips
For safety reasons, the park ing brake only re­
leases automat ica lly when the driver's door is
closed .
Emergency braking function
In the event that the conventional brake system
fails or locks .
.,. To brake your vehicle in an emergency, pull the
@ switch
q page 78, fig. 71 and hold it pulled.
.,. As soon as you release the @switch or acceler­
ate, the braking process stops.
Pulling and holding the@switch while driving at
a speed of about 2 mph (3 km/h) or h igher in i-
80
tiates the emergency b rak ing function . The veh i­
cle is braked at all four whee ls by activating the
hydraulic brake system . The brake performance is
s imilar to heavy brak ing.
q &
To he lp prevent activating the emergency braking
by mistake, an audib le wa rning tone (buzzer)
sounds when the @switch is pu lled . Emergency
braking stops as soon as the @switch is released
or the accelerator pedal is pressed.
A WARNING
Emergency braking should only be used in an
emergency, when the norma l brake pedal has
failed or the bra ke pedal is obstructed. During
emergen cy bra king, your ve hicl e will bra ke
similar to he avy braking. ESC and the asso ci­
ated components (ABS, ASR, EDL) canno t
overcome the laws of physics. In corners and
when road o r weathe r cond itions are bad, a
fu ll brake applicat ion can cause the veh icle to
skid or the rear end to break away, which in­
creases the risk of an accident.
Hill hold
App lies to vehicles: wit h Hill Hold
Hill hold makes it easier to start on hills.
Req uirement: The driver door must be closed and
the engine must be running.
The system is activa ted when the brake peda l is
pressed whi le the vehicle is statio nary .
To prevent the vehicle from roll ing ba ck when
st art ing, the brake power is held fo r a b rief mo­
ment afte r releas ing the b rake pedal. During this
time, you can easily begin to move your vehicle.
A WARNING
-The inte lligent technology of Hill Hold can­
not overcome the limitations imposed by
natura l physical laws. The increased comfort
offered by Hill Hold shou ld not cause you to
take safety r isks.
- Hill Hold cannot hold the vehicle in all hill
start sit uat ions (for example, if the ground
is s lippery or icy).

Automatic transmission
-If the engine must run while you are work­
ing in the engine compartment with the
hood open, make sure a gear is not engag­
ed . The selector lever must be firmly in the
P position and locked in place and the park­
ing brake must be set ¢
page 198. Other­
wise, the vehicle could begin moving when
the engine speed is high, even with the
parking brake set.
0 Note
- When stopping on an incline, do not try to
hold the vehicle in place by pressing the ac­
celerator pedal while a driving gear is se­
lected. This can cause the automatic trans­
mission to overheat and can damage it. Ac­
tivate the parking brake or press the brake
pedal to prevent the vehicle from rolling.
- Allowing the vehicle to roll when the engine
is stopped and the selector lever is in the N
position will damage the automatic trans­
mission because it is not lubricated under
those circumstances.
- The transmission can overheat and be dam­
aged under certain driving and traffic condi­
tions such as frequent starts, creeping for a
long time, or stop-and-go traffic . When the
5] or. indicator light turns on, stop the
vehicle at the next opportunity and let the
transmission cool¢
page 88.
-Allowing the vehicle to roll when the engine
is stopped will damage the S tronic trans­
mission because it is not lubricated
¢ page 2 54, Towing with a tow truck.
(D Tips
For safety reasons, the parking brake only re­
leases automatically when the driver's door is
closed.
Hill descent control
Applies to veh icles: w ith S tron ic transm ission
The hill descent control system assists the driv­
ing when driving down declines.
Hill descent control is activated when the selec­
tor lever is in the Dor S position and you press
86
the brake pedal. The transmission automatically
selects a gear that is suitable for the incline. Hill
descent control tries to maintain the speed ach­
ieved at the time of braking, within physical and
technical limitations. If may still be necessary to
adjust the speed with the brakes. Because hill de­
scent control cannot shift down farther than 3rd
gear, it may be necessary to shift into tiptronic
mode in very steep areas . In this case, shift into
1st or 2nd gear in tiptronic mode to use the en­
gine's braking force to relieve the brakes.
Hill descent control switches off once the decline
levels out or you press the accelerator pedal.
On vehicles with a cruise control system*
¢
page 94, hill descent control is also activated
when the speed is set .
&_ WARNING
Hill descent control cannot overcome physical
limitations, so it may not be able to maintain
a constant speed under all conditions. Always
be ready to apply the brakes.