2012 AUDI A8 brake sensor

Instrument s and warnin g/indic ator ligh ts 13
I
USA mod els: Safety systems
[j
Tank system
¢ page 18 ¢page 21
'
m
Canada models: Safety systems
•
Windshield washer fluid level
¢page 18 ¢page
21
I]
Electronic Stability Control (ESC)
!I
Windshield wipe rs
,I ¢ page 21
¢ page 18
- -
I!
Remote control key
Electronic Stability Control (ESC)
I
¢page BO
,I
¢page 18
~
Remote control key
USA models: ¢ page BO
rJ}E
Anti-lock brak ing system (ABS)
m
Battery in remote control key
defective ¢page29
¢ page 19
I Canada model s:
l:I
Defective light bu lb warn ing
•
Anti-lock braking system (ABS) ¢page 21
defective
Fog lights*
I ¢page 19
II ¢page 21
Worn brake pads
•
- -
¢page 19
•
Rear fog lights*
¢page 21
•
Electromechanical parking brake
¢page82
II
Headlight range control
¢page 21
•
Tire pressure mon itoring system
,I
mJ
adaptive light*
¢ page253 ¢page
21
1111&1
Tire pressure monitoring system
Light-/rain sensor faulty
m
¢page253
¢page 21
[m
Electronic power contro l - -
¢page20
•
Audi lane assist
¢page 96
g
Malfunction indicator Lamp (MIL)
,I
ti
Transmission
¢page20 ¢page
112
•
Engine speed limitation
Ii]
Transmission
¢ page 20
¢page 112
Ill
Engine oil level
Im
Electronic steering column lock
¢page 17
¢page 17
•
Engine oil sensor
Im
Engine start system
¢ page20
¢page 17
r.
Battery
,100
Dynamic steering *,/
¢ page 16
¢page22
--

18 Instruments and warning/indicator lights
If the indicator light turns on and the mes­
sage appears, there is a ma lfunction in the en ­
g ine start system.
Drive to your authorized Aud i dealer immedi­
ate ly to have the malfunction cor rected .
0 Air suspension
• Air suspension: system fault. Can contin­
ue slowly with max. 35 mph .
There is a malfunction that can result in re­
stricted driving stability .
Ca refully drive at a maximum speed of 35
mph
(60 km/h) to your authorized Audi dealer
or qualified workshop to have the malfunction
corrected .
• Air suspension: service mode. Vehicle
can only be moved with restrictions
Carefully drive to your authorized Audi dealer
or qualified workshop immediately to have
the service mode deactivated.
Ill Air suspension fault
There is a system ma lfunction that can result
in restr icted driving stability or reduced
ground clearance.
Drive to your authorized Audi dea ler immedi­
ate ly to have the malfunction corrected.
IIJ Air suspension: vehicle too low. Ground
clearance reduced
The ground clea rance is ve ry low due to a sys­
tem malfunct ion. Wait until the air suspen­
sion system has restored normal ground clear­
ance . Otherwise, conditions such as an uneven
road surface can lead to ve hicle damage.
~/ !f Safety systems
The fl (USA models) ;BI (Canada models) in­
d icator light monitors the safety systems e.g.
a ir bags, pretensioners and illum inates for a
few seconds each time you switch the ignition
on .
If the
I (USA models) ;BI (Canada models)
indicator light does not go out, or if it illumi- nates while you are driving, or if it starts to
blink,
then there is a malfunction somewhere
in the system.
If the light does not illuminate
when you switch the ign it ion on, th is also
means there is a malfunct ion.
A WARNING '"--
If you have a ma lfunction in the safety sys-
tems, contact your authorized Audi dea ler
imme diately. Otherwise the safety sys­
tems may not work properly in an acci­
dent.
fJJ [}, Electronic Stability Control (ESC)
This warning/indicator light monitors the
Electronic Stability Control.
When you switch the ignition on, the indicator
light
G1 turns on briefly to check the function.
If the
J.iJ ind icator lamp blinks wh ile driving,
the ESC or ASR (Anti-Slip Regulation) is active­
ly regulating.
If
the DJ ind icator lamp illuminates, the sys·
tern has switched the ESC off.
If the indicator light fi turns on, the ESC was
switched to ESC sport mode with the button
[!] c::, page 187. If this is case, you can reacti­
vate the ESC by switching the ignition off and
then on aga in. The warning/indicator light
should go out to show that the system is fully
functional again .
Stability program and ABS fault! See own­
er 's manual
If the indicator light DJ and the ABS indicator
li ght
m (USA models) ;II] (Canada models)
turn on and the message appears, there is a malfunction in the ABS system or electronic
differential lock. Th is also interrupts the ESC.
The brakes still funct ion wit h their normal
power, but ABS is not active .
Drive to your authorized Audi dealer immedi­
ately to have the malfunction corrected .
If the battery terminals were disconnected
and re-connected, the vehicle was jump start-
ed or the battery is very weak, the ESC sensor .,,.

20 Instruments and warning /indicator lights
If the warning light illuminates, immediately
contact your authorized Audi dealer or quali­
fied workshop to have all brake pads inspect­
ed. On USA models the warning light
El
comes on together with the warning light
- · Both sets of brake pads on an axle
must always be replaced at the same time .
A WARNING
Driv ing with bad brakes can cause a colli­
sion and serious personal injury.
-If the warning light El and the warn ing
light
- 1) with the message Brake
pads!
comes in in the inst rument cluste r
display, immediately contact your au­
thorized Audi dealer or qualified work­
shop to have all brake pads checked or
replaced if necessary.
EPC Electronic power control
This warning/indicator light monitors the
electronic power control.
The~ warning/indicator light (Electronic
Power Control) illuminates when you switch
the ignition on as a function check.
@ Tips
If this warning/indi cator light ill uminates
while you are driving, then there is a mal­
function in the engine electronics. Have
the malfunction corrected as soon as pos­
sible by your authorized Aud i dea ler or
qualified repair facility.
o Malfunction Indicator Lamp (MIL)
The Malfunction Ind icator Lamp (MIL) is part
of the On-Board D iagnostic (OBD II) system .
The symbol
¢4ii lights up when the ignition is
switched on and w ill turn off after the engine
has started and has sett led at a constant idle
speed. This ind icates that the MIL is working
properly.
l ) - : USA mod els only
-
The warning light illuminates when there is a
malfunction in the engine electronic system.
Contact your authorized Audi dea ler and have
the malfunction corrected.
An improperly closed fuel filler cap may also
cause the MIL light to illuminate
¢page 217.
For more information ~ page 26.
!?'i Engine speed limitation
Applies to vehicles: with engine speed limitatio n
Ill Engine speed maximum XXXX RPM
The eng ine speed is automatically limited to
the speed displayed in the driver information
system . This protects the engine from over ­
heating.
T he eng ine speed limitation deactivates once
the engine is no longer in the critical tempera­
ture range and you have re leased the accelera­
tor pedal once.
If the engine speed limitation was activated
by an engine control malfunction, the indica­
tor light~ also turns on. Make sure that the
speed does not go above the speed displayed .
Drive to your authorized Audi dealer immedi­
ately to have the malfunction corrected .
~ .. Engine oil level
II Add oil, max. x qt (l). You may continue
driving
When the symbol II and driver message ap­
pear, add the amount of oil appearing in the
display at the next opportunity¢
page 225.
~,.. Engine oil sensor
II Oil level! Sensor defective
If the symbol illuminates, contact your au­
thorized Audi dealer and have the oil sensor inspected . U ntil you have this done, check the
o il level each time you refuel just to be on the
safe side ~
page 224.

Audi adapt ive crui se c ontrol an d bra kin g guard 8 7
Audi adaptive cruise
control and braking
guard
Introduction
App lies to vehicles: with Audi adaptive cruise control
The adaptive cruise control system assists the
driver by regu lating vehicle speed and helping
to maintain a set distance to the vehicle
ahead, within the limits of the system . If the
system detects a moving vehicle up ahead,
adaptive cruise control can brake and then ac­
celerate your vehicle . Th is he lps to make driv­
ing more comfortable both on long highway
stretches and in stop-and-go traffic.
The braking guard system can warn you about
an impending collision and initiate braking maneuvers ¢
page 93.
Adaptive cruise control and Audi braking
guard have technica l limitations that you
must know, so p lease read this section care­
fully, understand how the system works and use them properly at all times.
General information
General information
Applies to vehicles: with Audi adaptive cruise control
Fig. 86 Front of the veh icle: sensors and video came ra
The areas that conta in the radar and ultrason ­
ic sensors and the v ideo camera ¢
fig. 86
must neve r be covered by stickers or other ob­
jects or obstructed w ith dirt, insects, snow or
ice that will interfere w ith the adaptive cruise
control system and Audi braking guard. For in­
formation on cleaning , refer to ¢
page 205.
The same applies for any modifications made
in the front area.
T he function of the Adaptive cruise cont ro l
system and A udi braking guard is limited un­
der some conditions.
- Objects can on ly be detected when they are
w ith in sensor range
¢page 89, fig. 89 .
-The system has a limited ability to detect
objects that are a shor t distance ahead,
off
to the side of your vehicle or moving into
your lane.
- Some kinds of ve hicles are hard to detect;
for examp le motorcycles, vehicles with high
ground clearance or overhanging loads may
be detected when it is too late or they may
not be detected at a ll.
- Stationary objects¢
page 88.
-When driving throug h curves ¢ page 88.
& WARNING
Always pay attent ion to traffic when adap ­
tive cruise contro l is switched on and brak­
ing g uard is active. As the driver, you are
still respons ible for start ing and for ma in­
taining speed and distance to other ob­
jects . Braking guard is used to assist you .
The driver must a lways take action to avo id
a collis ion. The driver is a lways responsible
for braking at the co rrect time.
- Improper use of adaptive cru ise control
can cause collisions, other acc idents and
serio us pe rsonal in jury.
- Never let the comfort and conven ience
that adaptive cruise control and Audi
braking guard offer dist ra ct you from the
need to be a lert to t raff ic condi tions and
the need to remain in full con trol of yo ur
vehicle at a ll times,
- Always remember that the adaptive
cruise contro l and Audi braking guard
have limits -they will not s low the vehi ­
cle down or maintain the set d istance
when you drive towards an obstacle or
something on or near the road that is not
mov ing, such as vehicles stopped in a
traffic jam, a stalled or disabled vehicle .
I f regis tered by the radar sensors,

88 Audi adapti ve cruise control and bra king gu ard
vehicles or obstacles that are not moving
can trigger a collision warning and if con­
firmed by the v ideo camera, an acute col­
lis ion warn ing .
- For safety reasons, do not use adaptive
cruise co ntrol when driving on roads with
many curves, when the road surface is in
poor condit ion and/or in bad weather
(such as ice, fog, gravel, heavy rain and
hydroplan ing) . Using the system under
these cond it ions cou ld result in a co lli ­
sion .
- Swi tch adap tive c ruise control off tempo­
rar ily when driv ing in turning lanes, on
expressway exits or in construction
zones . This prevents the vehicle from ac­
celerat ing to the set speed when in these
situations.
- The adapt ive cruise control system wi ll
not brake by itse lf if you put your foot on
the accelerator pedal. Doing so can over­
ride the speed and d istance regulation .
- When approaching stationary objects such as stopped traff ic, adaptive cruise
co ntrol will not respond and braking
guard w ill have limited function.
- The adapt ive cruise control system and
braking guard do not react to people, an­
imals, objects c rossing the road or on­
coming objects .
- The function of the radar senso rs can be
affected by reflective objects such as
guard rai ls , the entrance to a tunnel,
heavy rain or ice.
- Never follow a ve hicle so closely that you
cannot stop your vehicle safe ly. The
adaptive cruise contro l canno t slow or
brake the vehicle safely when you follow
another vehicle too closely. Always re­
member that the automatic braking
function cannot br ing the vehicle to a
sudden or emergency stop under these condit ions.
- To prevent unintended operation, always switch ACC off when it is not being used. (D Note
The sensors can be displaced by impacts or
damage to the bumper, wheel housing and
underbody. That cou ld affect the adaptive
cruise control system and brak ing guard.
Have your authorized Aud i dea ler or au ­
thorized Audi Service Facility check their
funct ion .
In curves
Applies to vehicles: with Audi adaptive cru ise contro l
I
Fig. 87 Ex ampl e: dri ving in to a curve
When d riving into a curve c> fig. 87 and out of
a curve, the ad aptive cruise control may react
to a vehicle in the next lane and apply the
brakes. You can override or prevent the brak­
i ng by pressing the acce lerator pedal b riefly .
' Stationary objects
Applies to vehicles: with Audi adaptive cruise control
Fig. 88 Exampl e: objec t ch anging l anes and sta tio nar y
object
T he adaptive cru ise control system only reacts
to objects that a re mov ing o r that the system
has already detected as moving . For examp le,
if a vehicle @, which has already been detect-
ed by the adaptive c ruise contro l, tu rns off o r
ch anges lane and ano ther stationary veh icle .,.

Audi adaptive cruise control and braking guard 93
Audi braking guard
Description
Applies to vehicles: with Audi adaptive cruise control
Fig. 96 Instrument cluster: approach warning
Audi braking guard uses radar sensors and a
video camera. It also functions within the lim­
its of the system when adaptive cruise control
is switched off.
What can Audi braking guard do?
When detected in time, the system can assess
situations when a vehicle ahead brakes sud­
denly or if your own vehicle is traveling at a
high speed and approaching a vehicle up
ahead that is moving more slowly . Audi brak­
ing guard does not react if it cannot detect
the situation.
The system advises you of various situations:
- The
distance warning is given if you are too
close to the vehicle ahead for a long time. If
the vehicle ahead brakes sharply, you will not be able to avoid a collis ion. The indicator
light
I i n the display comes on .
- The
approach warning is given when a de­
tected vehicle up ahead in your lane is mov ­
i ng much more slowly than you are or if it
brakes sharply . When this warning is given,
it may only be possible to avoid a collision
by swerving or braking sharply. The indicator
light
I and indicator in the display will warn
you about the danger
c::> fig . 96. You will a lso
hear an acoustic signal.
If you do not react fast enough or do not react
at all to the situation, Aud i braking guard will
11
This is not ava ilable in som e coun tri es.
intervene by braking and the message braking
guard intervention
will appear.
- If a coll is ion is imminent, the system wi ll
first provide an
acute warning by briefly and
sharply applying the brakes.
- If you do not react to the acute warning,
braking guard can brake with increas ing
force within the limits of the system. This
reduces the vehicle speed in the event of a
collision.
- The system can initiate complete dece lera­
tion shortly before a collision
1>. Full deceler­
ation at high speeds occurs only in vehicles
with adaptive cruise control and side assist
(pre sense plus).
- If the Audi braking guard senses that you
are not braking hard enough when a colli­
sion is immi nent, it can increase the braking
force.
- The pre sense functions also engage when a
collision is imm inent
c::> page 185 .
Which function s can be controlled?
You can switch Audi braking guard and the
distance/approach warning on or off in the
MMI c::> page 94, Settings in the MMI.
A WARNING
Lack of attention can cause collisions, oth­
er accidents and serious personal injuries .
The Audi braking guard is an assist system
and cannot prevent a collision by itself.
The driver must always intervene. The driv­
er is always responsib le for braking at the
correct time.
- Always pay close attention to traffic,
even when the Audi braking guard is
switched on. Be ready to intervene and
be ready to take complete control when ­
ever necessary. Always keep the safe and
legal distance between your veh icle and
veh icles up ahead.
- Audi brak ing guard works within limits
and will not respond outside the system
lim its, for example when approaching a

94 Audi adap tive cruise control and br aking guard
stopped vehicle or stationary obstacle
(end of a traffic jam or veh icle that has
broken down in traffic).
- Always remember that the radar sensor
for the Audi braking guard works only
within defined detection and range limits
that may prevent the proper detection of
other vehicles .
- 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.
- Reflective surfaces includ ing crash barri­
ers or tunnel entrances may impair the
func tion of the radar sensor.
{D) Tips
- You can cancel the braking w ith increas­
i ng force that is initiated by the system
by braking yo urself, by accelerating no­
ticeab ly or by swerving.
- Audi braking guard error messages
¢page 94.
- Keep in mind that braking gua rd can
brake u nexpectedly. Always secure any
ca rgo or objec ts th at yo u are transport­
i ng to reduce the risk of damage or in­
ju ry.
Settings in the MMI
Applies to vehicles: with Audi adaptive cruise co ntrol
.. Se lect: I CARI function button > Ca r sys tem s
control button > Drive r assist > Audi b rak­
ing guard .
System -
Switch Audi braking g uard On and
Off . When you switch the ignition on, the
message
Aud i braking gua rd off appears if
the system is switched off.
Ea rly warnin g -The distance and approach
warn ings in the display can be switched
On /
Off .
(D Tips
- Your settings are automatically stored
and ass igned to the remote control key being used at the times the settings are
made.
- If you switch the ESC to sport mode, A u­
di braking gua rd switc hes off a utomat i­
cally r=:>page
189.
- Switch A udi braking guard off when you
are loading the vehicle onto a vehicle car­
rier, train, ship or other type of transpor­
tat ion. This can prevent undesired warn­
ings from the braking guard system.
Messages
Applies to vehicles: with Aud i adaptive cru ise contro l
ACC unavailable
ACC and b raking gua rd: unavailable
T he system cannot detect moving vehicles up
ahead correctly and is switched off. The sen­
sors have been displaced or a re not working
proper ly . The Audi pre sense functions may a l­
so be affected. Drive to your authorized Audi
dealer or authorized A udi service facility im­
med iate ly to have the malfunction corrected.
ACC: unavaila ble at thi s time. No sen sor vi­
sion
ACC and braking guide: un ava ilabl e at thi s
time . No s ensor vi sion
Th is message appears if the sensor v iew is ob­
structed, for examp le by leaves, snow, heavy
spray o r d irt. Clean the sensors
r=;, page 87,
fig. 86 .
ACC: unavailabl e at this time. Inclin e too
s teep
The road exceeds the max imum possible an­
gle for proper adaptive cru ise control opera­
t ion. Adaptive cru ise cont rol is switched off.
ACC: only selector lever pos itions D , S or M
available
Se lect the D, Sor M selector lever position .
ACC: un available at thi s time . Parking brake
s et
T he adapt ive cru ise control system switches
off au tomatically if the par king b rake is set. .,.

266 Fuses and bulbs
Fuse panel @ (brown)
No. Equipment
1 Headlight control switch
2 Emergency start coil (key
identification)
3 Rear door
control module
(driver's side)
5 Horn
6 Interior lights
(headliner)
Steering column lever, mul-
8
tifunction steering wheel
controls, steering wheel
I heating
10 Power steering column ad-
justment
11 Driver door control module
12 Diagnost
ic connector, light/
rain sensor
14 Power steering column ad-
justment
15 Power
steering, AC compres-
sor
16 Brake booster
Fuse panel © (black)
No. Equipment
1 Front seat heating
2 Windshield wiper
3 Front exterior lighting
4 Sun roof
5 Driver power window
6 Driver seat (pneumatic)
7 Panoramic
sunroof
8 Dynamic steering
9 Front exterior lighting
10 Windshield/headlight
wash-
er system
11 Rear power window (driver's
side)
Panoramic sunroof
Amps
5
5
7,5 15
7,5
10/5
5
7,5 10
25
20 15
Amps
30
30
30 20
30 15
20
35
30
35
30
40
Front passenger side cockpit fuse
assignment
Fig. 206 Front passe nger side cockpit: fuse pane l with
plastic bracket
Fuse panel ® (black)
No. Equipment Amps
1 Anti-theft alarm system
5
2 T
ransmission control mod-
15
ule
3 Front climate control fan 40
4 Engine supply 35
6 Engine
control module
5
7 Front passenger door con-
7,5
trol module
8 Front passenger
power win-
30
dow
9 ESC control module 10
10 E5C control modu le 25
11 Right rear power window
30
12 Front
passenger seat (pneu -
15
matics)