Start and driving
Driving
St ar
t and driving
Starting and stopping the
engine Ignition lock Fig. 136
Ignition key positions. Key positions
››
› Fig. 136
Ignition off. Key can be removed from the
vehicle.
Ignition is switched on. Preheating occurs
in diesel vehicles . Starting the engine.
1 2
3 Locking and unlocking the steering wheel
Driving
Note
The recommended gear indication turns off
when the clut ch pedal is pr
essed or when
the lever is removed from the tiptronic posi-
tion. Steering
Inf ormation r
elating to different ve-
hicle processes. Electro-mechanical power steering adapts
el
ectr
onically to the speed of the car, torque
and steering angle.
Even if the power steering fails or the engine
is stopped, it is possible to continue to rotate
the steering wheel as long as the key remains
in the ignition lock, but more force must be
applied.
Steering assist
This help assists the driver in critical situa-
tions. It recommends turning the steering
wheel to perform a corrective manoeuvre
(counter-steering), turning slightly to avoid
skidding ››› . WARNING
Steering assist helps the driver in critical
sit uations. The driv
er is the person who has
to control the vehicle's steering at all times. Control lamp
v
It lights up red
Faulty steering.
Do not continue driving, st op the v
ehicle as soon as
possible and in a safe manner.
Take the vehicle to a specialised workshop and have
the fault repaired as soon as possible. v
It lights up yellow
Limited steering operation.
Driv e car
efully to a specialised workshop to have the
steering checked.
If the warning light does not come on again after re-
starting the engine and driving a short distance, it is
not necessary to check the steering.
OR: The 12-v olt batt
ery was disconnected and re-
connected.
Drive a short distance at 15-20 km / h (9-12 mph). v
It flashes yellow
The steering column is jammed.
When st opped, t
urn the steering wheel in both direc-
tions.
OR: The st eering column does not unlock or lock.
R
emove the key from the ignition switch and recon-
nect it. Consider the messages shown on the instru-
ment panel display.
Do not continue driving if the steering column re-
mains locked after switching on the ignition. Seek
specialist assistance. The control lamp should light up for a few
seconds when the ignition is s
wit
ched on. It
should go out once the engine is started. WARNING
Never ignore the warning lamps or messag-
es.
Driving
Electronic differential lock (EDL)*
When the EDL det ects wheel
spin, it brakes
the spinning wheel and directs the power to
the other driven wheel. This function is active
up to approximately 100 km/h (62 mph).
To prevent the disc brake of the braked wheel
from overheating, the EDL cuts out automati-
cally if subjected to excessive loads. The ve-
hicle can still be driven. The EDL will switch on
again automatically when the brake has
cooled down.
Tractor-trailer sway mitigation*
If the vehicle is pulling a trailer, it will control
the following: tractor-trailers tend to sway.
When the swaying of the trailer is felt by the
vehicle and detected by the ESC, it will auto-
matically brake the towing vehicle within the
limits of the system and mitigate the sway.
Tractor-trailer sway mitigation is not available
in all countries ››› page 248
.
Electronic engine torque management
(XDS)*
When taking a curve, the driveshaft differen-
tial allows the outer wheel to turn at a higher
speed than the inner wheel. In this way, the
wheel that is turning faster (outer wheel) re-
ceives less drive torque than the inner wheel.
This may mean that in certain situations the
torque delivered to the inner wheel is too
high, causing the wheels to spin. On the other hand, the outer wheel is receiving a lower
drive t
orque than it could transmit. This can
cause a loss of grip on the drive axle, in this
case the front axle, which results in under-
steer or “lengthening” of the trajectory.
The XDS can detect and correct this effect
via the sensors and signals of the ESC.
Via the ESC, the XDS will brake the inside
wheel and counter the excess driving torque
of that wheel. This means that the requested
trajectory is much more precise.
XDS works in combination with the ESC and is
always active, even when ASR is disconnec-
ted, or when the ESC is in Sport mode or dis-
connected.
Multi-collision brake
The multi-collision brake consists of automat-
ic braking activated by the Airbag control
unit. It is activated when, in the event of an
accident, the Airbag control unit detects de-
celerations above the activation level, and
braking is managed by the ESC system.
In the event of an accident, the multi-collision
brake can help the driver by braking to avoid
the risk of skidding during the accident and
causing other collisions.
The following actions control automatic brak-
ing during the accident: