2009 AUDI A4 CABRIOLET check engine light

Driver information display
On-Board Diagnosti cs
Fig . 15 Location of
Data Link Connector
(DLC)
On-Board Diagnostics monitors the components of your emission
control system. Each controlled component in your engine system
has been assigned a code. In case of a malfunction, the component
will be identified and the fault stored as a code in the control module memory .
Th e MIL lamp may also illuminate if there is a leak in the on -board
fuel vapor recovery system. If the light illuminates after a refuelling,
pull off the road and stop the vehicle, then check that the fuel filler
cap is properly closed
=> page 246.
In order to make an accurate diagnosis, the stored data can only be
displayed using special diagnostic equipment (generic scan tool for
OBDl.
In order to connect the special diagnostic equipment, push the plug
into the Data Link Connector (DLC). The DLC is located to the right of
the engine hood release lever=> fig. 15.
Your authorized Audi dealer or a qualified service station can inter ­
pret the code and perform the necessary repair. •
Electronic speed limiter
Your vehicle may be factory equipped with tires that are rated for a
maximum speed of 130 mph (210 km/h). This is less than the
maximum speed of your vehicle . To reduce the risk of sudden tire
failure and loss of control if the vehicle is operated at excessive
speeds, your vehicle also has an electronic speed limiter . The elec­
tronic speed limiter prevents your vehicle from going faster than the
tire speed rating. For more information=>
page 279, "New tires and
replacing tires and wheels".
If the engine control unit receives faulty vehicle roadspeed signals,
the Malfunction Indicator Lamp (Mill will illuminate. If this
occurs, contact the nearest authorized Audi dealer for assistance.
& WARNING
Always observe the posted speed limits and adjust your speed to
suit prevailing road, traffic and weather conditions. Never drive
your vehicle faster than the maximum speed rating of the tires installed. •
Auto-Check Control
Introduction
The Auto-Check control monitors the function of certain vehicle
features and components. It simply makes sure these features and
components are working properly. The Auto-Check control works as
long as the ignition is on, as well as whenever the vehicle is driven.
If a component is malfunctioning or if the need for an urgent repair
has been detected, this will appear in the instrument cluster display.
You will also hear an audible warning tone. The displays are color
coded in either red or yellow depending on their level of priority. .,_

USA models: if there is a malfunction in the ABS system, the <­
warning/indicator light illuminates along with the BRAKE system
malfunction warning/indicator light=>&.
Canada models: if there is a malfunction in the ABS system, the
warning/indicator light illuminates together with the
(Ci)) brake
system malfunction warning/indicator light=>& .
& WARNING
• Always observe the warnings in => page 242, "Engine compart­
ment", before opening the engine hood and checking the brake
fluid.
• Driving with low brake fluid is a safety hazard! Stop the car and
get professional assistance.
• If the brake system warning/indicator light illuminates
together with the ABS warning/indicator light, then the ABS system is malfunctioning. The rear wheels could quickly lock up
when you apply the brakes. This could lead to loss of control and
your vehicle could slide! Drive carefully to the nearest authorized
Audi dealer and have the malfunction corrected. •
Engine cooling system malfunction -L
A malfunction in the engine cooling system must be
repaired as soon as possible.
When the -t symbol in the display flashes, then either the
engine coolant
temperature is too high, or the coolant level
is too low. In addition to the symbol, the following message
also appears in the display:
Switch off engine, check coolant level
Pull off the road and stop the vehicle.
- Turn off the engine.
Controls and equip ­
ment
Driver information display
Check coolant level ~ page 258.
-Add coolant if necessary~ page 259.
- Continue driving only after the engine coolant
warning/indicator light goes out.
- Contact your authorized Audi dealer for assistance if
necessary.
If the engine coolant level is correct, then the radiator fan may be
the cause of the malfunction.
If the generator warning/indicator light should also illuminate
=>
page 22, then the fan belt may be damaged.
& WARNING
• If your vehicle should break down for mechanical or other
reasons, park at a safe distance from moving traffic, turn off the
engine and turn on the hazard warning lights
=> page 82, "Emer­
gency flasher
A".
• Never open the hood if you see or hear steam or coolant
escaping from the engine compartment -you risk being scalded.
Wait until you can no longer see or hear steam or coolant escaping.
• The engine compartment of any vehicle is a dangerous area.
Before you perform any work in the engine compartment, turn of
the engine and allow it to cool. Follow the warning stickers
=> page 242, "Engine compartment" .
0 Note
Do not continue driving if the -F-symbol illuminates. There is a
malfunction in the engine cooling system -you could damage your
engine. •

II
Light/rain* sensor defective
Worn brake pads
USA m odels :
Speed warning 1
Canad a m od els:
Speed warning 1
Dynamic headlight range con trol*
defective
Adaptive Light* defective
Windshield washer fluid level low
U SA mod els:
Speed warning 2
Canada mod els:
Speed warning 2
Battery voltage too high or too low
D efective light bu lb
Tire pressure monitoring system* Loss of air pressure
Tire pressure monitoring system*
System not available
~ page33
~ page 33
~ page34
~ page 34
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~ page 34
~ page34
~ page 34
~ page35
~ page 43
~ page46 I
Ye llow symbols indicate a priority 2 malfunction -Warning!
When a yellow symbo l appears, a warning tone wi ll sound
once.
Check the displayed function as soon as possible. If more than one
priority 2 ma lfunction is detected, all symbols will appear one after
the other for about two seconds. •
Controls and equip­
ment
Driv er inf ormati on di spl ay
Fuel supply too low l
When the -,symbol illuminates, this means there is about 2 to 2.5
gallons (8 to 10 litres) of fue l left in the fuel tank . Time to refuel!
~ page 245. •
Engine oil level '7.:.
When the-=· symbol illuminates, check the engine oil level as soon
as possib le ~
page 254 . Add oil if necessary ~ page 255. •
Engine oil sensor defective • ..
If the .,_,ft symbol illuminates, contact your author ized Audi dea ler
and have the oil sensor inspected. Until you have this done, check
the oi l leve l each time you refuel just to be on the safe side
~ page 254. •
Applies to vehic les: with Lighting package
Light/rain* sensor defective >
- Automa tic headl ight s/autom atic wiper s def ective
If the symbol il luminates, the light/rain sensor has failed. For safety
reasons the low beams are turned on permanently with the switch
in
AUTO . However, you can continue to turn the lights on and off
using the light switch. In the case of a defect in the rain sensor, the
windsh ield wiper lever functions are still avai lable. Have the
light/rain sensor checked as soon as possible at a dealership. •
Worn brake pads J
r Brake p ad s!

Openin g and clo sin g
How is th e a nti-th eft ala rm switch ed off whe n
t riggered ?
The alarm system is switched off when you unlock the vehicle using
the remote control or when the ignition is switched on. The a larm
will a lso switch itse lf off when it comes to the end of its cycle.
Em erg en cy flashe r
The emergen cy flashe r will blink briefly when the doors, engine
hood and rear lid are properly closed .
If the emergency flashers do not blink, check the doors, engine hood
and r ear lid to make sure they are properly closed . If you close a
door, the hood or the rear lid w ith the anti-theft a larm switched on,
the emerg ency flashers will blink only aft er you have clos ed the
door or lid.
[ i ] Tips
• For the anti -theft alarm system to function properly, make sure
all vehicle doo rs and windows are closed before leaving the vehicle .
• When you open the vehicle from the driver's door using the key,
the c entral locking switch will work only af ter you hav e swi tched on
the ignition. •
Tilt sensors ~
The tilt sensors trigger an alarm if they detect vehicle
movement.
N
ij
:c .,
"'
Fig . 49 D river's do or,
rear botto m: ti lt se nso r
sw itch
Sw itch off the tilt se nsors i f you are go ing to have your
ve hicle tr ansported .
Switch off the tilt s ensors
- Press the switch A located in the driver's door=> fig. 49 .
Lock the ve hicle.
When you turn off the tilt sensors, the diode in the switch -lQ wi ll illu ­
minate. Also , the indicator light in the driver's door wil l illuminate
for about three seconds . After you lock the vehicle, the indicator
light in the door trim will b link quickly for about three seconds . After
that, the blinking slows down.
The next time the vehicle is locked, the tilt sensors are automatically
turned on again .•

Clear vision
inst rument panel ill umination will automaticall y become dimmer
a s the daylight fades away and eventually will go out completely
when out side l ight i s very low . Thi s is to remind you , the dri ver , to
s witch on the headlights befor e it g ets too dark.
• Canada model s: instrument panel illumination will stay bright
re gardles s of the intensity of ambient light . Alway s be aware of
c hange s in outside light cond itions while you are d riv ing . Resp ond
in time to f ading dayl ight by turning the ligh t switch to po sit ion
io
(or "AUTO" if your car is equipped with this feature) to turn on your
he adl ights . •
Ap plie s to vehic le s: wi th x eno n hea dlig ht s
Xenon headlights
After s tarting the engine, the xenon headligh ts are automatically
adjusted to the load and angle of the vehicle (for example, during
acce leration and brak ing) . This prevents oncoming tra ffic from
experienc ing unnecessa ry glare from your head lights .
If the system is not operating properly, a warning sy mbol in the
Auto -Check Contro l is displayed:::::,
page 34. •
Emergency flasher &.
The emergency flasher makes other mot orists aw are that
y o u or your vehicle are in an emergency situation.
1Jia---------------...,i ij ::c .,
"'
-
Fig. 9 3 Ce nter
cons ole: e mergen cy
fla sher swit ch
Press the sw itch ~~fig . 93, to sw itch the emergency
fl ash er o n or o ff.
When the emergency flasher is on, al l four turn signa l blink at the
same time . The turn signal indicator lights¢¢ in the instrument
cluster, as we ll as the light in the emergency flasher sw itch
t!:;,,. b link
likewise .
The emergency flasher will automatica lly switch on if you are in an
accident where the airbag has deployed .
[ i ] Tips
You should switch on the emergency flasher when :
• you are the last vehicle stand ing in a t raffic jam so that any other
veh ic les coming can see you , or when
• your vehic le has broken down or you are in an emergency situa ­
tion, or when
• your veh ic le is being towed by a tow truck or if you are towing
another vehicle behind you .•

Clear vision
& WARNING
• Wiper blade s are cru cial fo r safe driving ! O nly when they are in
good cond it ion are they able to clear the window s properly to
p ro vi de un comp romi sed vis ibility . Worn or damaged wiper blade s
are a safety hazard
=> page 8 7, "In stalling new w ipe r blades "!
• The rain sen sor is onl y de signed to a ssis t and support the
driver. It remain s ent irely the driver' s re spon sibility to monitor
o ut side weather condit ion s a nd to manually acti vate the wipers a s
soon a s rain or drizzle reduces vi sibility through the wind shield .
• The wind shield mu st not be treat ed w ith water -repellent mate ­
rials. They can increase glare under poor visibility conditions such
a s w etne ss, darknes s, or when the sun i s lo w on t he horizon . In
addition , they can cause the windshield wipers to chatter .
0 Note
In freezing or near freezing conditions :
• Always check that the wiper blades are not frozen to the g lass
before you turn the wipers on. Loosen a wiper b lade which is frozen
in place before operating the wipers to prevent damage to the wiper
b lade or the wipe r motor.
• Do not use the wipers to clear a frosted window . Using the
wipe rs as a convenient ice scraper wil l destroy the wiper blades .
• Before you take your vehicle to an automatic car wash , make sure
you have the wi ndshield w iper system switched off (lever in position
0), otherwise the windshield wiper system could get damaged in the
car wash if it should suddenly come on .
[ i ] Tips
• The rain sensor is part of the interva l wiping system . Turning off
the ignition will also deactivate the rain sensor. To reactivate the sensor, switch off the interva l wiping function, then switch it back
on aga in. • I
f you switch off the ignition with the windshield wiper lever sti ll
in the interva l wipe position and then come back a while late r and
drive off, the rain sensor will reactivate itself after the vehicle speed
has exceeded 4 mph (6 km/h) .
• Worn or dirty windshield wiper b lades cause smearing which
can affect the operation of the rain sensor . Check the condition of
your windshield wiper b lades regularly .
• Make sure the washer fluid reservoir in the engine co mpartment
is topped off before going on a long trip. Look up=>
page 266 for
checking and f illing the washer container .•
Headlight washer system
The headlight washer system cleans the headlights.
Operate the w indshie ld wiper/washer system, leve r posi­
tion
© =>page 85, fig. 97, w ith the head lig hts switched
on
by h old ing the lever for longer than o ne second .
The washer jets extend forward out of the front bumper driven by
water pressure to s pray the front headlights with water .
You should inspec t the head lights regu larly (for examp le when refu ­
e ling) and c lean off any so lid dirt or insects from the lenses .
To ensure the sys tem works proper ly in winter, keep the washer jets
free of snow and
remove any ice using a de -icing spray .•

___ ln_ te_ ll..,,ig ..,_ e_ n_t _t_ e_ c_ h _ n_o _ l_o _,.g= y,_ __________________________________________ _
& WARNING (continued)
• Do not "ride the brakes" by resting your foot on the pedal when
you do not intend to brake. This may cause the brakes to overheat, premature wear and increased stopping distance.
• Under certain climatic and operating conditions such as
passing through water, 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 .
Cautiously apply brakes for a test. Brakes will dry and ice coatings
will be cleaned off after a few cautious brake applications .
• Driving for an extended period of time on salt-covered roads
without using your brakes can also affect braking efficiency. Clean
off accumulated salt coating from brake discs and pads with a few
cautious brake applications.
• If you damage the front spoiler, or if you install a different
spoiler, be sure the air flow to the front brakes is not obstructed.
Otherwise the brake system could overheat reducing the effective ­
ness of the entire brake system.
• Failure of one brake circuit will impair the braking capability
resulting in an increased stopping distance. Avoid driving the
vehicle and have it towed to the nearest Audi dealer or qualified
workshop. u
Brake booster
The brake booster adds extra braking power.
The brake booster works with vacuum pressure which is created
only when the engine is running~ &.
& WARNING
• Never let the vehicle 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
& WARNING (continued)
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 under braking.
The ABS contributes effectively to vehicle control since it prevents
the wheels from
locking when the brakes are applied. This means
that the vehicle remains steerable and is less likely to skid.
With ABS you do not need to pump the brake. Just hold the brake
pedal down.
However , do not expect that the ABS shortens braking distance
under
all circumstances. When driving on gravel or on newly fallen
snow on top of icy surfaces, braking distance may be even longer,
therefore, under these circumstances, it is especially important that
you drive slowly and with great care.
How the ABS system works
An automatic check is made when a speed of about 4 mph (6 km/h)
is reached. When this happens, a pumping noise can be heard.
If an individual wheel begins to rotate too slowly in relation to
vehicle speed and tends to lock, the ABS automatically reduces brake pressure to prevent that wheel from locking.
This automatic adjustment process will cause a
slight vibration of
the brake pedal and some noises to alert you that vehicle speed
must be adapted to existing road and traffic conditions.
& WARNING
Although the ABS is very effective, always remember that braking
capability is limited by tire traction . Always adjust your driving
speed according to the road and traffic conditions. Do not let the .,_

& WARNING (c ont in u ed)
ext ra sa fe ty a fforded by the ABS tempt you into t ak in g ex tr a risks .
The ABS cannot overco me th e law s of ph ysics.
[ i J Tips
• If ABS is not funct ioning properly, a warning light will come on.
See
=> page 20.
• If a fau lt occurs in the ABS, the EDL is also not funct ion ing . This
is indicated by the ABS warning light.
Brake assistant
T he brake assistant is designed to achieve the optimum
braking effect.
The brake assistant helps to increase the effective braking power
and thus to achieve a shorter stopping distance . If the driver
presses the brake pedal very quick ly, the brake assistant automati ­
cally boosts the braking force to the maximum level, up to the point
where the anti -lock brake function (ABS) intervenes to stop the
wheels from locking. You should then keep the brake pedal pressed until the vehicle has braked to the required speed. The brake assis­
tant switches itself off as soon as you re lease the brake peda l.
The brake assistant will not be operative if there is a malfunction in
the ABS .
& WARNING
Please remembe r that the accident risk always in cre a se s if you
dri ve to o fa st, e spe cially in cor ner s o r on a slipp ery road , or if you
follow th e vehicle ahead of you too clos ely. An increased a ccident
ri sk ca nnot be comp en sa ted even b y the brake assista nt , s o
alwa ys maintain a safe spe ed . •
Controls and equip­ ment Safety first Vehicle operation
Int
ellig ent tec hnol ogy
Servotronic® -advanced power
steering system
The power steering systems uses the power of the
running engine to allow precise steering with little effort.
The advanced Servotronic ® power steering system senses the road
speed and electronically adjusts power assistance to provide
comfortab le and safe steering response exactly matched to the
vehicle speed.
Power steering will not work if the engine is off. As a result, the
steering whee l wil l be hard to turn .
The power steering fluid level is checked during the schedu led
maintenance services.
0 Note
If there is an electronic ma lfunction, servotronic will still function
like a conventional power steer ing system, providing a constant
steering support force that is no longer proportionate to the vehicle
speed. This is most noticeable when tu rning the steering whee l at
low speeds (for examp le when parking), -more effort wil l be
requi red than usual.
• Be aware of the different than usual steering response and
adjust you r steering force accordingly .
• Have the problem checked and set right by an Audi dealer as
soon as possible .
[ i J Tips
• When the engi ne is running, never hold the steering whee l
turned all the way to the right or to the left for longer than 15
seconds. The power steering pu mp will overheat the hydraulic fluid
if you keep holding the steering wheel turned a ll the way. This is
likely to damage the power stee ring system.
~
Vehicle care Do-it-yourself service Technical data