2008 AUDI A5 differential

Instruments and warning/indicator lamps 18Anti-lock brake system (ABS)

The warning lamp monitors the ABS and the electronic
differential lock (EDL).The warning lamp
 lights up for a few seconds when the ignition
is switched on and while the engine is being started. The lamp goes
out again once the system has run through an automatic test
sequence.
There is a fault in the ABS if:
•
the warning lamp
 does not light up when the ignition is
switched on,
•
the warning lamp does not go out again after a few seconds,
•
the warning lamp lights up when the vehicle is moving.
The vehicle can still be braked in the normal way (except that the
ABS control function is out of action). Please take the vehicle to a
qualified workshop as soon as possible. For further information on
the ABS ⇒page 197.
If a fault occurs in the ABS, the ESP warning lamp will also light up.
Fault in the main brake system
If the ABS warning lamp
 lights up together with the brake
warning lamp
 ⇒page 31, this indicates a fault in the ABS func-
tion, and possibly a malfunction in the main brake system as well
⇒.
If there is a malfunction in the brake system the symbol
 will light
up in the instrument cluster. Please refer to ⇒page 31.
Fault on the electronic differential lock (EDL)
The EDL works in conjunction with the ABS. If a malfunction should
occur in the EDL, this is indicated by the ABS warning lamp .
Please take the vehicle to a qualified workshop as soon as possible.
For further information on the EDL ⇒page 199.
WARNING
•
Before opening the bonnet and checking the brake fluid level,
observe the warning information on ⇒page 231, “Working on
components in the engine compartment”.
•
If the brake warning lamp
 should light up together with the
ABS warning lamp
, stop the vehicle immediately and check the
brake fluid level in the reservoir. If the fluid level has dropped
below the "MIN" mark you must not drive on - otherwise there may
be an increased accident risk. You should obtain professional
assistance.
•
If the brake fluid level is OK, the fault in the brake system may
have been caused by a failure of the ABS control function. As a
result the rear wheels can lock relatively easily when braking. This
could cause the tail of the vehicle to skid sideways. Drive carefully
to the nearest qualified workshop and have the fault rectified.
Applies to vehicles: with Audi hold assistAudi hold assist

This warning lamp monitors the Audi hold assist function.Audi hold assist helps the driver to keep the vehicle stationary while
the engine is running, for instance on steep gradients, at traffic
lights or in stop-and-go traffic. When the Audi hold assist function
is on, you don't have to keep your foot on the brake to prevent the
vehicle from accidentally rolling away. Once it detects that the
vehicle is stopped, Audi hold assist keeps the vehicle stationary. The
green symbol
 in the instrument cluster indicates that the func-
tion is activated. You can now take your foot off the brake pedal.
When the vehicle has been stationary for an extended period, Audi
hold assist will automatically apply the parking brake. In this case,
the green symbol  will change to red
.
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Intelligent technology 196Intelligent technologyElectronic stabilisation program (ESP)General notes
The electronic stabilisation program increases the car's
stability on the road.The ESP is designed to enhance the control over the vehicle in crit-
ical handling situations, such as when accelerating and cornering.
It reduces the tendency to skid under all road conditions and
improves the stability and roadholding of the vehicle. The system
works at all speeds.The anti-lock brake system (ABS), the electronic differential lock
(EDL) and the traction control system (ASR) are all integrated into
the electronic stabilisation program.
How the system works
The ESP control unit processes data from the three integrated
systems. It also processes additional inputs provided by other high-
precision sensors. These register the vehicle's rotation about the
vertical axis (yaw rate), lateral acceleration, brake pressure and
steering wheel angle.
The system uses the steering wheel angle and road speed to calcu-
late the changes of direction intended by the driver, and constantly
compares them with the actual behaviour of the vehicle. If the
desired course is not being maintained (for instance, if the car is
starting to skid), then the ESP compensates automatically by
braking the appropriate wheel.
The forces acting on the braked wheel effectively bring the car back
to a stable condition. If the car is oversteering (rear wheels losing
grip first) the brake application is concentrated on the outside front
wheel; if the car is understeering (front wheels losing grip first), ESP
brakes the inside rear wheel. This automatic brake application is
accompanied by characteristic noises.
The ESP works in conjunction with the ABS ⇒page 197. If a
malfunction should occur in the ABS, the ESP will also be out of
action.
Switching on
The ESP is switched on automatically when the engine is started
and performs a self-test routine. As soon as this routine is complete,
the system switches back to normal operating mode. You can press
the button ⇒fig. 203 or ⇒fig. 204 to switch on the ESP or traction
control system (ASR) if they have been switched off. The message
ESP/ASR on will appear briefly in the display.
Fig. 203 Without MMI:
Centre console with
ESP switchFig. 204 Centre
console with ESP
switch
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Intelligent technology199
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Note
To ensure that the ASR works properly, all four wheels must be fitted
with identical tyres. Any differences in the rolling radius of the tyres
can cause the system to reduce engine power when this is not
desired. Also refer to ⇒page 245, “Replacing wheels and tyres”.Electronic differential lock (EDL)
The electronic differential lock monitors the speed of the
driven wheels.General notes
The electronic differential lock (EDL) helps the car to start moving,
accelerate and climb a gradient in slippery conditions where this
may otherwise be difficult or even impossible.
How the system works
The EDL acts automatically. With the aid of the ABS sensors
⇒page 197, the system monitors the rotational speed of the driven
wheels on each axle. Whenever it detects a significant difference in
the speed of the driven wheels of one axle (for example, if the road is
slippery on one side) the system applies the brake to slow down the
spinning wheel so that more of the power is directed to the other
wheel of this axle (or to the three other wheels on vehicles with four-
wheel drive). This function is active up to about 100 km/h. The brake
system will make noises while it is working.
Driving away from a standstill
Sometimes one wheel has less grip and starts spinning, for
example, if one of the driven wheels is on ice. In this case, keep
pressing the accelerator gradually until the car starts moving, even
though the wheel with less grip will still spin.
Overheating of the brakes
To prevent the disc brake of the braked wheel from overheating, the
EDL cuts out automatically if subjected to excessive loads. The car remains operational and will behave in the same way as a car
without EDL.
The EDL will switch on again automatically when the brake has
cooled down.
WARNING
•
When accelerating on a uniformly slippery surface (for instance
all four wheels on ice or snow), press the accelerator gradually and
carefully. The driven wheels may otherwise start to spin (in spite
of the EDL), which would impair the car's stability and could lead
to an accident.
•
Even with EDL, you should always adjust your speed to suit the
conditions. Do not let the extra safety provided tempt you into
taking any risks when driving – this can cause accidents.Note
If the ABS warning lamp lights up, this can also mean there is a fault
in the EDL. Please contact a qualified workshop as soon as
possible.BrakesNew brake pads
New brake pads do not give full braking effect for the first 400 km,
they must first be “bedded in”. However, you can compensate for
the slightly reduced braking effect by applying more pressure on
the brake pedal. Avoid placing a heavy load on the brakes during the
running-in period.
We ar
The rate of wear on the brake pads depends a great deal on how you
drive and the conditions in which the vehicle is operated. Negative
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Intelligent technology201
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Power steering (servotronic)The power steering assists the driver when turning the
steering wheel (with the engine running).The power steering assists the driver by reducing the force needed
to turn the steering wheel. The degree of power assistance is
adapted electronically, depending on the speed.
If a fault should occur in the servotronic system the power steering
will still operate. The degree of power assistance will, however, no
longer adapt to different speeds. If the electronic regulating system
is not working properly, this is most noticeable when turning the
steering wheel at low speeds (for instance when parking) – more
effort will be required than usual. The fault should be corrected by
a qualified workshop as soon as possible.
The power steering does not function when the engine is switched
off. In this case the steering wheel is very hard to turn.
If the steering is held at its turning limit when the car is stationary,
this will place an excessive load on the power steering system. In
this case, the power steering system will make noises. It will also
reduce the idling speed of the engine.
Caution
Do not keep the steering in the full-lock position for longer than
15 seconds when the engine is running – this could cause damage
to the power steering system.
Note
•
If the power steering should fail at any time or the engine is
switched off (for instance when being towed), the car can still be
steered. However, more effort will be required to turn the steering
wheel.
•
If the system is leaking or malfunctioning, please take the car to
a qualified workshop as soon as possible.
•
The power steering requires a special hydraulic fluid. The fluid
reservoir is located at the front of the engine compartment on the
left ⇒page 232. The correct fluid level in the reservoir is important
for the power steering to function properly. The hydraulic fluid level
is checked at the Inspection Service.
Applies to vehicles: with four-wheel driveFour-wheel drive (quattro
®)
On quattro models the engine power is distributed to all
four wheelsGeneral notes
On four-wheel drive vehicles, the engine power is distributed to all
four wheels. The distribution of power is controlled automatically
according to your driving style and the road conditions. Also refer
to ⇒page 199, “Electronic differential lock (EDL)”.
The four-wheel drive is specially designed to complement the supe-
rior engine power of your Audi. This combination gives the car
exceptional handling and performance capabilities – both on
normal roads and in more difficult conditions, such as snow and ice.
Even so (or perhaps especially for this reason), it is important to
observe certain safety points ⇒.
Winter tyres
Thanks to its four-wheel drive, your car will have plenty of traction
in winter conditions, even with the standard tyres. Nevertheless, we
still recommend that winter tyres or all-season tyres should be fitted
on all four wheels when winter road conditions are expected, mainly
because this will give a better braking response.
Snow chains
On roads where snow chains are mandatory, this also applies to cars
with four-wheel drive ⇒page 248, “Snow chains”.
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Index305
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data Speed warning . . . . . . . . . . . . . . . . . . . . 28
Yellow symbols . . . . . . . . . . . . . . . . . . . 34
Driver messages . . . . . . . . . . . . . . . . . . . . . 30
Driving abroad . . . . . . . . . . . . . . . . . . . . . . 205
Headlights . . . . . . . . . . . . . . . . . . . . . . 205
Unleaded fuel . . . . . . . . . . . . . . . . . . . . 205
Driving away from a standstill . . . . . . . . . 122
Driving away when towing a trailer . . . . 123
Driving safety . . . . . . . . . . . . . . . . . . . . . . 163
Driving time . . . . . . . . . . . . . . . . . . . . . . . . . 25
Dust filter
Deluxe automatic air conditioner . . . . 93
Deluxe automatic air conditioner plus . .
101
DVD player . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Dynamic gear control program . . . . . . . . 133
EEasy-entry function . . . . . . . . . . . . . . . . 71, 73
Economical driving . . . . . . . . . . . . . . . . . . 206
EDL
SeeElectronic differential lock . . . . . . . 18
Electric seat adjustment
SeeSeat adjustment . . . . . . . . . . . . . . . 72
Electric windows . . . . . . . . . . . . . . . . . . . . . 50
Central locking system . . . . . . . . . . . . . 50
Controls . . . . . . . . . . . . . . . . . . . . . . . . . 50
Convenience open/close function . . . . 50
Malfunctions . . . . . . . . . . . . . . . . . . . . . 51
Settings . . . . . . . . . . . . . . . . . . . . . . . . . 51
Electrical accessories
SeeElectrical socket . . . . . . . . . . . . . . . 88Electrical socket . . . . . . . . . . . . . . . . . . 87, 88
Electro-mechanical parking brake . . . . . . 124
Auto release function . . . . . . . . . . . . . 122
Driving away from a standstill . . . . . . 122
Driving away when towing a trailer . . 123
Emergency braking function . . . . . . . 123
Malfunction . . . . . . . . . . . . . . . . . . . . . 123
Operation . . . . . . . . . . . . . . . . . . . . . . . 121
Parking . . . . . . . . . . . . . . . . . . . . . . . . . 122
Releasing and applying . . . . . . . . . . . . 121
Warning lamp . . . . . . . . . . . . . . . . . . 18, 19
Electronic differential lock
How the system works . . . . . . . . . . . . 199
Warning lamp . . . . . . . . . . . . . . . . . . . . . 18
Electronic immobiliser . . . . . . . . . . . . . . . . 14
Electronic stabilisation program
How the system works . . . . . . . . . . . . 196
Warning lamp . . . . . . . . . . . . . . . . . . . . . 16
Emergency braking function . . . . . . . . . . 123
Emergency key . . . . . . . . . . . . . . . . . . . . . . 41
Emergency release
Ignition key . . . . . . . . . . . . . . . . . . . . . . . 41
Emission control systems
Catalytic converter . . . . . . . . . . . . . . . . 205
Diesel particulate filter . . . . . . . . . . . . 205
Emissions . . . . . . . . . . . . . . . . . . . . . . . . . . 293
Engine compartment
Safety notes . . . . . . . . . . . . . . . . . . . . . 231
Engine compartment layout . . . . . . . . . . 232
Engine data
SeePerformance, weights and
dimensions . . . . . . . . . . . . . . . . . . . . 295Engine hood
SeeBonnet . . . . . . . . . . . . . . . . . . . . . . 230
Engine management
(EPC) warning lamp . . . . . . . . . . . . . . . . 15
Engine oil . . . . . . . . . . . . . . . . . . . . . . . . . . 233
Checking oil level . . . . . . . . . . . . . . . . . 234
Consumption . . . . . . . . . . . . . . . . . . . . 234
LongLife Service . . . . . . . . . . . . . . . . . . 233
Topping up . . . . . . . . . . . . . . . . . . . . . . 234
See alsoPerformance, weights and
dimensions . . . . . . . . . . . . . . . . . . . . 295
Engine oil capacity
SeePerformance, weights and
dimensions . . . . . . . . . . . . . . . . . . . . 295
Engine oil pressure
Warning lamp . . . . . . . . . . . . . . . . . . . . . 33
Engine oil sensor
Malfunction . . . . . . . . . . . . . . . . . . . . . . 37
Environmental compatibility . . . . . . . . . . 207
Environmental tips
Filling the tank . . . . . . . . . . . . . . . . . . . 228
Heated rear window . . . . . . . . . . . 98, 107
Leaks . . . . . . . . . . . . . . . . . . . . . . . . . . . 231
Roof carrier . . . . . . . . . . . . . . . . . . . . . . . 85
EPC
SeeEngine management . . . . . . . . . . . 15
ESP
SeeElectronic stabilisation program . . 16
Ethanol fuel . . . . . . . . . . . . . . . . . . . . . . . . 227
Exterior mirrors . . . . . . . . . . . . . . . . . . . . . . 67
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