2008 AUDI A4 AVANT brake sensor

Driver inf ormation di spl ay
priority 2 malfunction is detected, al l symbols will appear one after
t he other for about two seconds. •
Applie s to ve hicles: with Ligh ting pac kage
Light/rain* sensor defective fif>
~o Aut om atic hea dlig ht s/a utom atic w ipers defe ct iv e
If the symbol il luminates, the light /rain sensor has failed. For safety
reasons the low beams a re turned on permanently with the switch
in
AUTO. H owever, you can continue to turn the lights on and off
using the light sw itch . In the case of a defect in the ra in se nsor, the
windshield wiper lever functions are still available. Have the
l ight/ra in sensor checked as soon as poss ible at a dealersh ip .•
Fuel supply too low flt)
When the .ffi symbol illuminates, th is means there is about 2 to 2 .5
gallons (8 to 10 l itres) of fue l left in the fue l tank. Time to refuel!
=> page 268 . •
Checking the engine oil level ~ ..
When the ~ symbol illum inates, check the engine o il leve l as soon
as
possib le => page 277. Top off the oil at your ear liest opportunity
=> page 278 . •
Engine oil sensor defective ~ ...
If the ~-symbo l il lum inates, contact your authorized Audi dea ler
and have the oil sensor inspected . Until you have this done, check
the oi l leve l each t ime you refuel just to be on t he safe side
=> page 277. •
Worn brake pads 0
If the O symbo l illuminates, contact your authorized Audi dealer to
have the front brake pads inspected (on that occasion have the rear
brakes inspected as we ll to be safe) .•
Speed warning 1 8 (USA models)/ 0 (Canada
models)
I f the 0 symbo l il luminates, this means you are driving faster than
the set vehicle speed. Slow
down! => page 35. •
Applies to ve hicles : w ith d ynami c head light rang e adjus tment
Headlight range control defective {a:>
If the t0 illuminates, the dynamic head light range control is no
longer working properly. Have the system checked a nd repaired at
your Audi dealer .•
t·,···
Windshield washer fluid level too low <;p
If the O symbol illuminates, add windshield washer fluid to the
washer system and a lso fo r the headlight washer system*
=> page 291. •
Speed warning 2
0, (USA models)/ 9. (Canada models)
If the 0 symbol illum inates, this means you have driven faster than
the second set vehic le speed . S low
down!=> page 35 . •

-L-__;l.:..n ..::t ..::e :.:..11 :.:..ig ,.,_;: e:.:..n .:.. t:....:. te.::..::. c.:..h :.:..n.:.. o::..:..: lo~g~ y ___________________________________________ _
Intelligent technology
Notice about data recorded by
vehicle control modules
Your vehicle is not equipped with an Event Data Recorder (EDR),
installed by some manufacturers for the express purpose of
capturing data for retrieval after an accident or crash event . EDR's
are sometimes called "crash recorders" .
Some state laws restrict the retrieval or downloading of data stored
by EDR's that were insta lled in a vehicle for the express purpose of
retrieving data after an accident or crash event without the owner's
consent.
Although your vehicle is not equipped with an EDR, it is equipped
with a number of electronic control modules for various vehicle
systems such as, for example, engine function, emission control, as
we ll
as for the airbags and safety belts.
These electronic control modules also record vehicle-related data
during normal vehicle operation for diagnostic and repair purposes .
The recording capacity of the electronic control modules is limited
to data (no sound is recorded) and only a small amount of data is
actually recorded over a very limited period of time and stored when
a system fault or other condition is sensed by a control unit. Some
of the data then stored may relate to vehic le speed, d irection,
braking as well as restraint system use and performance in the
event of a crash or other condition . Stored data can only be read and
down loaded with special equipment. •
Electronic Stabilization Program (ESP)
General information
The ESP improves the vehicle stability.
(X) CD
Fig. 199 Center
console with ESP
sw itch
ESP is designed to he lp you maintain vehic le control in situations
where the car approaches the limits of "grip", especial ly when
acce lerating and cornering. ESP reduces the risk of skidding and
improves stability under al l road conditions.
The system operates across the entire speed range in combination
with the ABS system . If the Anti-Lock Brake System (ABS) malfunc ­
t ions, the ESP will a lso shu t down.
How the system works
The Anti-Lock Brake System (ABS), Electronic Differential Lock (EDU
and the Anti -Slip Regu lation System (ASR) are integrated in the e lec ­
tronic stabilization program . In addition to the data provided by
these functions, the ESP control unit requires additional measure ­
ment data provided by high performance sensors. The rotational
.,,.

-Intelligent technology
------~----- ~~--------------------------------------
one side), the spinning wheel is braked, thereby transferring power
to the other drive wheel or wheels (all- wheel drivel. This is done up
to a speed of about 60 mph (100 km/h). Noises from the brake
system signal that wheel spin is being control led.
Driving off
When driving off, always be sure to keep road conditions in mind as
you accelerate. If one drive wheel spins because it is on a surface
with less grip, gradual ly increase the pressure on the accelerator
pedal until the car starts to move. The wheel less able to transfer
power spins.
Overheating of brakes
To prevent the disc brake of the braked wheel from overheating if
subjected to excessive loads, the EDL cuts out temporarily. The
veh ic le remains operational and behaves in the same way as a
vehic le without EDL.
As soon as the brake has cooled down, EDL switches on again auto ­
matically.
& WARNING
• When accelerating on slippery surfaces, such as on ice or snow,
always be careful when depressing the accelerator pedal. Even
with the EDL working, the drive wheels can spin and reduce your
ability to control your car . - Risk of crash!
• The increased safety afforded by EDL does not mean that you
ca n take safety risks. Always adapt your driving style to the road
conditions and traffic situation.
[ i ] Tips
If a fault occurs in the ABS, the EDL is also not functioning. This is
indicated by the ABS warning
light => page 21. •
Anti-Slip Regulation System (ASR)
The Anti-Slip Regulation System prevents the driven
wheels from spinning when the car is accelerating.
General notes
The Anti-Slip Regulation System (ASR) is integrated in the electronic
stabilization program (ESP) . When the vehicle starts up and acceler­
ates, the wheels are prevented from sp inning by adjus tin g the
engine power to match the amount of grip availab le from the road
surface.
How the system works
ASR performs automatical ly, i.e . w ithout the driver's intervention.
With the aid of the ABS
sensors=> page 240, ASR monitors the
speed of the driven wheels. If the wheels start to spin, the engine
power is reduced automatically until the tires find enough grip to
lock onto the road surface. The system is active across the entire
speed range.
The ASR works in conjunction with the ABS. If a malfunction shou ld
occur in the ABS, the ASR will also be out of act ion.
Activation
The ESP is automatica lly activated when the eng ine is started, and
it performs a self-test. You can activate a deactivated ASR, if
requ ired, by pressing
t h e=> page 236, fig . 199 button .
Deactivation
You can deactivate the ASR, if required, by pressing the button (for
less than 3
seconds) => page 236, fig. 199. With the ASR deactivated,
the ESP check light flashes,
see=> page 22.
Normally, the ESP shou ld always be on, however, it may be advanta­
geous to turn off the system in certai n special cases when some
degree of wheel spin is desired such as :
• when driving with snow chains

___ T_ ir_e _ s_ a_ n
_ d_ w_ h_ e_ e_ls _________________________________________________ _
& WARNING
• Using incorrect or unmatched tires and / or wheels or improper
tire and wheel combinations can lead to loss of control , collision
and serious personal injury .
• Always u se tires , rims and wheel bolts that meet the specifica ­
tions of original factory -installed tires or other combinations that
have been specifically approved by the vehicle manufacturer.
• Tires age even if they are not being used and can fail suddenly ,
especially at high speeds . Tires that are more than 6 years old can
only be used in an emergen cy and then with special care and at
lower speed s.
• Never mount used tires on your vehi cle if you are not sure of
their "previous history." Old used tires may have been damaged
even though the damage cannot be seen that can lead to sudden
tire failure and loss of vehicle control.
• All four wheels must be fitted with radial tires of the same type ,
size (rolling circumference ) and the same tread pattern. Driving
with different tires reduces vehi cle handling and can lead to a loss
of control.
• If the spare t ire is not the same as the tires that are mounted
on the vehicle -for example with winter tires -only use the spare
tire for a short period of time and drive with extra care . Refit the
normal road wheel as soon as safely possible.
• Never drive faster than the ma ximum speed for wh ich the tires
on your vehicle are rated because tires that are driven faster than
their rated speed can fail suddenly .
• Overloading tire s cause heat build -up , sudden tire failure ,
including a blowout and sudden deflation and loss of control.
• Temperature grades apply to tires that are properly inflated and
not over or underinflated .
• For technical reasons it is not always possible to use wheel s
from other vehicles - in some cases not even wheels from the
same vehicle model.
& WARNING (continued )
• If you install wheel trim discs on the vehicle wheels, make sure
that the air flow to the brakes is not blocked . Reduced airflow to
the brakes can them to overheat , increasing stopping distances
and causing a collision .
• Run flat tires may only be used on vehicles that were equipped
with them at the factory. The vehicle must have a chassis designed
for run flat tires and a factory-installed tire pressure monitoring
s ystem that indicate s a loss of tire pressure . Incorrect use of run
flat tires can lead to vehicle damage or ac cidents . Check with an
authorized Audi dealer or tire specialist to see if your vehicle can
be equ ipped with run flat tires . If run flat tires are used , they must
be installed on all four wheels . Mixing tire types is not permitted.
0 Note
• For tec hnical r eas ons, it is no t gene rally possible to use the
whee l rims from other vehicles . ihis can hold true for wheels of the
same ve hicle type.
• I f the spare tire is different from the tires that you have mounted
on y our ve hicle (f or exampl e wi nter t ires or wide p ro fi le tir es), then
use the spa re tire fo r a short per iod of time on ly and d rive with extra
c a re . Rep lace the flat t ire wi th the ti re m atc h ing t he oth ers o n you r
vehic le as soon as possib le .
• If yo u should put diff eren t w heels a nd tires on yo ur vehi cle (e. g.
winter wheels and tires), you must be certa in that the wheels and
t ires a re co mpatibl e w ith the tire press ur e m onit orin g sys te m.
Otherwise the system will regist er a ma lfunction and a fau lt
mes sage wil l be d isp layed . Fo r mo re info rmation, contact yo ur Audi
dea ler .
0 Note
• When i nsta lling new ti res, be care fu l n ot to damage t he va lves o r
tire press ure mon itoring system* sensors . .,_

Fuses and bulbs -
----------------
0 Note No. Equipment Amps
• On no account should fuses be repaired (e.g. patched up with tin 13 Steering column module 10
foil or wire) as this may cause serious damage elsewhere in the elec -14 Brake lights 10
trical circuit or cause fire.
15 Instrument cluster, Navigation system 10
• If a fuse blows repeatedly, do not keep replacing it. Instead, have
the cause for the repeated short circuit or overload tracked and Garage door opener
5
fixed.
•
Level, tire pressure control, park assist,
17 light/rain sensor 10
Fuse list Automatic headlight range control, left 5
Fuses which can be replaced. 19 Fog lights, rear fog light 15
20
Not used
No. Equipment Amps
21 Not used
1 Air conditioner 10 Front doors 15
2
Footwell illumination 5 23 Rear doors 15
3 Heated washer jets 5 Central convenience electrical system 20
4 Radiator fan 5 25 Heater blower 30
5
Telephone, oil level sensor, multifunction 10 26 Rear window defogger 30
switch, rear heated Seat, shift gate
27 Socket for trailer towing (controller) 30
6
Air conditioner (air quality sensor), air pressure 5 28 Fuel pump 20 sensor
Electronic Stabilization Program (ESP), brake
29 Not used
7 light switch, clutch pedal switch, steering angle 10 Power sunroof 20
sensor Automatic transmission, mirror dimming, diag-
31 15 8 Telephone 5 nosis socket
9 Brake booster (vacuum pump) 15 Towing assembly 15
10
Automatic headlight beam adjustment, auto -5 33 Cigarette
lighter 20
matic headlight range control, right
Electrical socket 20
11
Airbag 5 35 Luggage compartment socket 20
12
Diagnosis socket 10 Windshield wiper system 30
Do -it -yourself service

111'1_....::::A::.:l:.!: p :.:h..:.: a:::.:: b:.::e :.:t::i c::.::: a.:..l ..:.: in :..:.:: d:.:e :.:x::..... ___________________________________________ _
A
ABS (Anti- lock Brake System)
Warning/indicator lights ... .... .... 21
Accessories . .... .... .... .... .... ... 348
acoust ic park assist . . . . . . . . . . . . . . . . . 139
Adap tive light .. ... .... ... .. ...... ... 75
defective . . . . . . . . . . . . . . . . . . . . . . . . 35
Adding Engine coo lant
282
Engine oi l ... ... .. .... .... ... .... 278
Windshield washer fluid .... .... .. 291
Additiona l accessories .. ...... ...... . 348
Additives Eng ine oi l .. ....... ....... ....... 278
Adjustable steering whee l column .. ... 134
Adjusting Instrument cluster il lumina tion ... .. . 15
Steering wheel co lumn . ...... .... 134
Advanced A irbag System . .... ... .... 191
Ch ildren ... ........... .... ... ... 211
Components ...... .... ... .... ... 194
Fr ont airbags . . . . . . . . . . . . . . . . . . . . 192
How the c ompone nts wo rk togethe r 195
Monitoring . . . . . . . . . . . . . . . . . . . . . . 198
PASSE NGER AIR BAG O FF light ..... 199
Weight -sensing mat ....... ... .... 211
Air conditioner . . . . . . . . . . . . . . . . . . . . . 128
See also Climate controls . . . . . . . . . . 125
Air conditioning Switching on and off 128
A ir distribution
C limate controls . ...... ... .... ... 130 Air outlets
Adjusting the outlets for rapid defrosting/de fogging .. ...... .... 131
Cl imate con trols ...... .... .... ... 131
Air quality sensor . . . . . . . . . . . . . . . . . . . 129
Air recirculation .. ... .... .... .... ... 128
Clima te controls .. .... ..... .. .... 129
When should I use the air recircu lation?
129
Airbag Warning/indicator lights .... ... .... 20
Airbag system . . . . . . . . . . . . . . . . . . 187 , 205
Car e ...... .... .... .... .... .... .. 201
Child restraints .... .... .... .... .. 212
Componen ts (front airbags) .... ... . 194
Danger of fitting a chi ld safety seat on the
front passenger seat . . . . . . . . . . . . 189
Disposal .. ....... .... .... .... ... 201
Front airbags . .... ... .... .... .... 191
How do the front
ai rbags work? .... 196
How many airbags does my vehicle have? 194
I mportant things to know ....... .. 1 87
I ndicator light ... .. .... .... ... ... 198
Monitoring . . . . . . . . . . . . . . . . . . . . . . 198
Repairs ...... .... ... .... .... .... 201
Side airbags ... ...... .... ... .. ... 203
Side curtain airbags (SIDEGUARD) .. 207
When must the sys tem be inspec ted? ...
198
Alloy w heels . .... .... .... .... .... .. 260
All -wh ee l driv e 242
Winter tir es ..... .... .... ... .. ... 310 A
lternator
See Generator . . . . . . . . . . . . . . . . . . . . 22
Aluminum al loy wheels . ...... .... ... 260
Ambient light ing . ....... .... ... .. .... 82
Anti-free ze
See Engine coolant system ........ 280
Anti -glare inside day -ni ght mi rro r .. ... . 90
An ti- lock B rake System (ABS)
How the ABS system works . ....... 240
Warning/indicator l ights ........... . 21
Anti -Slip R egulation Syst em (ASR)
How the sys tem works .... .... .... 238
An ti- theft systems
Anti -theft ala rm system .. ...... .... 64
Electronic immobilizer .. ... .... ... . 5 4
Tilt sensors . .... .... ... .... .... ... 65
Armrest Adjusting ...... .... ... .... ..... . 102
Storage bi n
Ashtray 1
02
Front . .... .... .... .... ... .... ... 119
Rear ...... .... .... .... ... .... ... 119
ASR Anti- Slip Regulation System .... ... 238
Asterisk What does it mean when something is marked with an asterisk? .. ... .... .. 6
Attachment hooks ... .... .... .... ... 112
Aud i Service Repa ir Manuals and Lite rature
346

___ A_l-=- p _h_ a_ b_e _t_ic _ a_l _in _ d_e _x ____________________________________________ _
Starting .. .. .. ...... .... .... 135, 136
Starting with jumper cables ... .... 330
Stopping . .... .... .... ... .... ... 137
Engine compartment ... .. .... .... ... 274
Safety instructions . . . . . . . . . . . . . . . 273
Working the engine compartment .. 273
Engine coolant system . ...... ...... . 280
Adding coolant .. ...... .......... 282
Checking coo lant leve l .. .. .... .... 281
Checking the engine coo lant leve l .. 281
Radiator fan . . . . . . . . . . . . . . . . . . . . . 283
Engine coolant temperature Gauge ...... ...... .... ........... 13
Engine cooling system Ma lfunction .. .... ..... .. .... .... . 31
Engine data ...... .... .... .......... 343
Engine hood Closing . ...... ..... .. .... ...... . 273
How to release the hood . . . . . . . . . . 272
Engine oil ...... .... .... .... ... .... 275
Adding ... .... ... .... .... ...... . 278
Additives . . . . . . . . . . . . . . . . . . . . . . . 278
Changing ... .. .... .... ...... .... 279
Checking the engine oi l level .. .... . 277
Indications and conditions requiring extra
checking ..... .. .... .... ... .... 277
Oil consumption .. .... .... ... .... 277
Oil grades . . . . . . . . . . . . . . . . . . . . . . . 275
Recommended o il check interva ls .. 277
Specification and viscosity . . . . . . . . 275
Engine oil level .. .... .... .... ... .... . 34
Engine oil pressure Malfunction ...... ..... .. .... .... . 32 Engine oil sensor defective
....... .... . 34
Environment Break -in period .. ...... .... .... .. 243
Catalytic converter .. ...... .... ... 244
Disposing of your vehicle battery ... 291
Driving at high speeds .. .... .... .. 245
Driving to minimize pollution and noise . 245
Fuel ... ...... .... ... .. .... .... .. 269
Fuel economy ....... ...... .... .. 245
Leaks under your vehicle ... .... ... 273
Letting the vehicle stand and warm up .. 246
Proper disposa l of drained brake fluid
284
Proper disposal of drained engine
coo lant ...... ............. ..... 282
Proper disposa l of drained engine oil
278 ,279
Recycling used eng ine oil .. .... ... 278
Un leaded fuel ..... .... ... .... ... 267
What should I do with an old battery?
291
EPC
See Electronic power control .. ... .. . 23
ESP
See Electronic stabi ll ization program
(ESP) . ... .... .... ........ ... 22, 236
Event Data Recorder (EDR) .. ....... .. 236
Expansion tank .. .... ... .... .... .... 281
F
Fahrenheit
Switching between Fahrenheit and Centigrade . ...... .... ...... .... 128
Fan Adjusting the fan speed .. ...... ... 129
Climate controls ................. 129
Radiator ...... .... .... ...... .... 283
Fastening eyes ... .... .... .... .... .. 108
Flat tire ............................. 50
Changing .. .... .... ... .... .... .. 318
Flat tire changing .. ...... .... .... .... 50
Floor mats .. ... ... .... .... .... .... . 172
Fog lights ........................... 76
Fo lding master key with remote control . 52
Foot pedals .. .. .. .... .... .... ...... 17 2
For the sake of the environment Gaso line fumes and the environment 269
Letting your engine warm up ....... 136
Reducing engine noise by early upshifting .... .... ... .... .... ... 13
Reducing engine noise by upshift ing
early . .... .... .... ... .... .... ... 13
Refueling .... .... .... ....... .... 269
Saving fuel by early upshifting . .... . 13
Saving fuel by upshifting early .. .... 13
Using the rear window defogger 131, 132
Front airbags
Description . .... .... ... .... .... .. 191
How they work .. .... ... .... .... .. 196
Front ashtray . . . . . . . . . . . . . . . . . . . . . . . 119
Front fog lights .... .... .... .... .... .. 76

___ A_,_ lp_h_ a_b_ e_ t
_ i_ c _ a_ l_ in_ d_ e_x ______________________________________________ _
Parking brake warning ..... .. .... .... . 29
Parking l ight
Defective . . . . . . . . . . . . . . . . . . . . . . . . 35
Park ing on a dec line (downhil l) ....... 138
Parking on an incline (uphill) ..... .... 138
Parktronic
See acoustic park assist . . . . . . . . . . . 139
Parts replacement . . . . . . . . . . . . . . . . . . 348
PASSENGER AIR BAG OFF light ........ 199
Passive safety system . . . . . . . . . . . . . . . 166
Pedals ............................ 172
Physical principles of a fronta l collision 177
Polishing . . . . . . . . . . . . . . . . . . . . . . . . . . 257
Power locking switch . . . . . . . . . . . . . . . . . 59
Rear ............................ 60
Power locking system . . . . . . . . . . . . . . . . 55
Convenience close/open feature ..... 59
Locking and unlocking the vehicle from
inside ........... ....... .... .... 59
Opening and c losing the windows ... 59
Operating locks from with key .. .... 58
Rear lid . .... ... .. .... .... .... .... 61
Remote control . . . . . . . . . . . . . . . . 53, 56
Unlocking and locking vehicle ....... 56
Power locks
Power sunroof ..... .... .... .... ... 69
Pow er outlets . . . . . . . . . . . . . . . . . . . . . . 121
Power roof ........ .... ... .. .... ..... 67
Power seats Adjusting the seatback ............. 99
Adjustment ........... .... .... ... 97
Pow er steering . . . . . . . . . . . . . . . . . 135 , 241 Power
sunroof
Emergency closing ................ 69
Power window switche ·s . ...... .... ... 65
In the driver's door ... .... ... .. .... 66
In the front passenger's door ....... 67
Reactivating the system ............ 67
Pregnant women Specia l considera tions when wearing a
safety belt . . . . . . . . . . . . . . . . . . . . . 183
Programming the Homelink® Universa l Re -
mote Contro l . . . . . . . . . . . . . . . . . . . 157
Prop er occupant seating positions .... 168
Proper safety be lt position . . . . . . . . . . . 182
P roper seating position
Front passenger . . . . . . . . . . . . . . . . . 169
Occupants . . . . . . . . . . . . . . . . . . . . . . 168
Rear passengers . . . . . . . . . . . . . . . . . 170
Protectiv e liner 113
a
Quartzclock ...... .... ........ ....... 14
quattro®
See All -whee l drive ............... 242
Question
R
What happens to unbelted occupants? ..
178
Why safety belts? . . . . . . . . . . . . . . . . 176
Radiator fan ...... ............. ..... 283
Radio Replacing ....................... 349 Rain sensor defective
... .. .... .... .... 34
Reading lights
Front ....... ...... .... ...... ..... 81
Rear .......................... 81, 82
Reararmrest . .... .... .... ....... ... 103
Rear ashtray ....................... 119
Rear fog lights .. ...... .... .... .... ... 76
Rear lid
Emergency un locking (on ly manually . 62
Locking/unlocking ............. .... 61
Rear light
Defective ........ .... .... .... .... . 35
Rear power locking switch ... .. .... .... 60
Rear seat bench .. .... .... ..... .. ... 104
Rear view mirror Inside rear view mirror ............. 90
Rear window defogger .... .... .... ... 131
Rearview mirror
See Mirrors ....................... 90
Red symbols .. ........... .... .... ... 30
Refuel ling .......................... 269
Release lever for hood .... ........ ... 272
Remote control . . . . . . . . . . . . . . . . . . . 53, 56
Assigning a seat position .. .... .... 102
Resetting remote control ........... 57
Unlocking and locking ............. 56
Remote master key
Battery replacement ....... ....... . 53
Check light ................ ...... . 53
Remote rear lid release .... ...... ..... 63
Removing luggage compartment cover/parti -
tion net ...... .... .... .... .... . 111