Automatic transmission
Automatic transmission S tronic, tiptronic
Introduction
The automatic transmission is controlled elec
tronically. The transmission upshifts or down
shifts automatically depending on which drive
program is selected.
When a
moderate driving style is used, the
transmission selects the most economical driving
mode. The transmission upshifts at a lower RPM
and downshifts at a higher RPM to improve fuel
efficiency.
The transmission switches to a sporty mode after
a kick-down or when the driver uses a
sporty
driving style
characterized by quick accelerator
pedal movements, heavy acceleration, frequent
changes in speed and traveling at the maximum
speed.
If desired , th e driver can also select the gears
manually (tiptronic mode) 9 page 110.
Various automatic transmissions may be instal
led, depending on the model:
S tronic transmission
The S tronic is a dual-clutch transmission. Power
is transferred using two clutches that work inde
pendently from one another. They replace the
torque converter used in conventional automatic
transmissions and allow the vehicle to accelerate
without a noticeable interruption in traction.
tiptronic transmission
In the tiptronic transmission, power is transfer
red by a torque converter.
106
Selector lever positions
Fig. 115 Display in the instrument cluster: selector lever
position
The selector lever position engaged appears next
to the selector lever as well as in the instrument
cluster display.
P -Park
In this selector lever position the transmission is
mechanically locked. Engage P only when the ve
hicle is
completely stopped¢&. in Driving the
automatic transmission on page 108.
To shift in or out of position P, you must first
press and hold the brake pedal and then press
the release button in the selector lever handle
while moving the selector lever to or from P. You
can shift out of this position only with the igni
tion on.
R -Reverse
Select R only when the vehicle is at a full stop
and the engine is running at idle speed¢&. in
Driving the automatic transmission on
page 108.
Before you move the selector lever to R, press
both the button in the handle of the selector lev
er
and the brake pedal at the same time.
When the ignition is on, the backup lights illumi
nate when the selector lever is moved into R.
N -Neutral
The transmission is in neutral in this position.
Shift to this position for standing with the brakes
applied
9 A in Driving the automatic transmis
sion on page 108.
...
-Before driving down a steep slope, reduce
your speed and shift into a lower gear with
"tiptronic" .
- Do not ride the brakes or press the brake
pedal too often or too long when driving
down a hill. Constant braking causes the
brakes to overheat and substantially re
duces braking performance, increases brak
ing distance or causes complete failure of
the brake system .
- To prevent the vehicle from rolling back
when stopping on inclines, always hold it in
place with the brake pedal or parking brake.
- Never hold the vehicle on an incline with a
slipping clutch. The clutch opens automati
cally when it becomes too hot from the
overload. An indicator lamp
l!] illuminates
and a driver message appears
¢ page 111
when the clutch is overloaded.
- If the engine must remain running, never
have any driving position engaged when
checking under the hood. Make sure these
lector lever has securely engaged and is
locked in P with the parking brake set
¢ page 216 . Otherwise, any increase in en
gine speed may set the vehicle in motion,
even with the parking brake applied .
(D Note
-When stopping on an incline, do not try to
hold the vehicle in place by pressing the ac
celerator pedal while a driving gear is se
lected . This can cause the transmission to
overheat and can damage it. Activate the
parking brake or press the brake pedal to
prevent the vehicle from rolling.
- Allowing the vehicle to roll when the engine
is stopped and the selector lever is in
N will
damage the transmission because it is not
lubricated under those circumstances.
(D} Tips
For safety reasons, the parking brake is re
leased automatically only when the driver's
safety belt is engaged in the buckle.
Automatic transmission
Hill descent control
Hill des cent control assists the driver when driv
ing down hills .
Hill descent control is activated when the sele c
tor lever is in the D or S posi tion and you press
the brake pedal. The transmission automatically selects a gear that is suitable for the incline. Hill
descent control tries to maintain the speed ach
ieved at the time of braking, within physical and
technical limitations . If may still be necessary to
adjust the speed with the brake pedal.
Hill descent control switches off once the hill lev
els out or you press the accelerator pedal.
On vehicles with a cruise control system*
¢ page 82, hill descent control is also activated
when the speed is set.
,&. WARNING
Hill descent control cannot overcome physical
limitations, so it may not be able
to maintain
a constant speed under all conditions. Always
be ready to apply the brakes.
109
