169
Driving
WARNING
● Never switch the engine off until the vehicle is stationary.
● The brake servo and the power steering system work only when the
engine is running. You need more strength to steer and brake the vehicle
when the engine is switched off. Given that you will be unable to steer
and brake as usual, this could lead to a risk of accidents and injuries.
CAUTION
If the engine has been running under high load for a long time, there is a
risk of heat building up in the engine compartment after the engine has
been switched off; this could cause engine damage. Therefore, you should
let the engine idle for approximately 2 minutes before you switch it off.
Note
After the engine is switched off the radiator fan may run on for up to 10 mi-
nutes, even if the ignition is switched off. It may also start running again af-
ter some time if the coolant temperature rises due to a build-up of heat un-
der the bonnet, or if the engine is already warm and the engine compart-
ment is heated up further by direct sunlight.
Start-Stop function* Description and operation
The Start-Stop function stops the engine when the vehicle is stop-
ped and starts it automatically when required.
– When the vehicle is stopped, put it in neutral and release the
clutch pedal. The engine will stop. –
When the clutch pedal is pressed, the engine starts again.
– The instrument panel display shows information about the sta-
tus of the Start-Stop function ⇒ Fig. 138.
Start-Stop function conditions
● The driver seat belt must be buckled.
● The bonnet must be closed.
● The engine must be at operating temperature.
● The steering wheel must not be turned more than 270°.
● The vehicle must not be on a steep gradient.
● The vehicle must not be in reverse.
● A trailer must not be connected.
● The temperature of the passenger compartment must be within the con-
venience limits ( ECON
button should not be selected).
● The windscreen de-mist function must be off.
● Otherwise it requires more than 50% of the airflow that the fan can sup-
ply.
● The temperature must not be set to HI or LO.
● The driver door must be closed.
● The diesel particulate filter must not be in regeneration mode, for diesel
engines.
● The battery charge must not be low for the next start.
● The battery temperature must be between -1 °C and 60 °C.
Start-Stop function interruption
In the following situations, the Start-Stop function will be interrupted and
the engine will automatically start:
● The vehicle starts moving.
● The brake pedal is pressed several times in a row.
● The battery has been discharged excessively.
Safety FirstOperating instructionsPractical TipsTechnical Specifications
170Driving
● The Start-Stop System is manually deactivated.
● The windscreen de-mist function is turned on.
● The temperature of the passenger compartment exceeds the comfort
limits (button ECON
should not be selected).
● If more than 50% of the airflow that the fan can supply is ordered.
● Temperature setting HI or LO is selected.
● The engine coolant temperature is insufficient.
● The alternator is faulty, for example the V-belt has ruptured.
● If any of the conditions described in the previous section are not fulfil-
led.
WARNING
Never allow the vehicle to move with the engine off for any reason. You
could lose control of your vehicle. This could cause an accident and seri-
ous injury.
● Power steering does not work when the engine is not running. That is
why it is much more difficult to turn the steering wheel.
● Turn off the Start-Stop system when driving through water (fording
streams, etc.).
Note
● For vehicles with the Start-Stop function and a manual gearbox, when
the engine is started, the clutch must be pressed.
● When the conditions for the Start-Stop function are not fulfilled, the in-
strument panel displays the Start-Stop indicator dimmed.
● If the steering wheel is turned more than 270°, Stop will not function;
however, the angle of steering wheel turn does not affect starting the vehi-
cle. Activating and deactivating the Start-Stop function
Fig. 137 The Start-Stop
function button.
Every time the ignition is switched on, the Start-Stop function is au-
tomatically switched on.
Manually deactivating the Start-Stop function
– Press the ⇒ Fig. 137 button located on the centre console.
When the Start-Stop function is deactivated, the pushbutton in-
dicator lights.
– If the Start-Stop function is operating then the engine starts im-
mediately.
Switching the Start-Stop function on manually
– Press the ⇒ Fig. 137 button located on the centre console.
The indicator on the button will go out.
173
Driving
Releasing the handbrake
– Pull the lever up slightly and at the same time press in the re-
lease button ⇒ Fig. 142 (arrow).
– Keep the release button pressed and push the lever all the way
down ⇒
.
If you drive by mistake with the handbrake still applied, you will hear a
warning buzzer and the display will show the message: Handbrake on
The handbrake warning switches on after driving for 3 seconds at speeds
above 5 km/h.
The handbrake warning lamp lights up when the handbrake is applied
with the ignition on.
WARNING
Please note that the handbrake should be released all the way. If the
handbrake is only partially released, this will cause the rear brakes to
overheat, which can impair the function of the brake system and could
lead to an accident.
CAUTION
Once the vehicle has come to a standstill, always apply the handbrake firm-
ly and then, on a manual gearbox, engage a gear, or select P on an auto-
matic. Parking
The following points will ensure there is no risk of the vehi-
cle rolling away accidentally after it is parked:
– Use the foot brake to stop the vehicle.
– Apply the handbrake firmly.
– Switch the ignition off.
– On a manual gearbox engage 1st gear or on an automatic move
the selector lever to P ⇒
.
When parking on slopes:
Turn the steering wheel so that the, if the vehicle moves, it will do so to-
wards the curb.
WARNING
● Do not leave anyone (especially children) in the vehicle when it is
locked. Locked doors could delay assistance in an emergency, potentially
putting lives at risk.
● Never leave children unsupervised in the vehicle. They could release
e.g. the handbrake or gear lever, moving the vehicle and causing an acci-
dent.
Safety FirstOperating instructionsPractical TipsTechnical Specifications
186Driving
If you select a gear which is lower than the gear shown on the instrument
panel display ⇒ Fig. 151, the gearbox will only shift down when there is no
longer a risk of over-revving the engine.
When the vehicle slows down (for instance when braking), the gearbox au-
tomatically shifts down into the next gear when the minimum engine speed
is reached.
Changing down to a lower gear increases the engine braking effect on
downhill gradients.
When the accelerator pedal is pressed right down past the point of resist-
ance at full throttle, the gearbox will select a lower gear ratio, depending on
road speed and engine speed.
Back-up programme
A backup programme is in place if a fault should occur in the
control system.
The automatic gearbox switches to the back-up programme if a fault should
occur in the control system. This is indicated by a gear pinion symbol which
lights up on the instrument panel display.
It is still possible to move the selector lever to all positions. The manual
shift programme (tiptronic) is not available when the back-up programme is
active.
Vehicles with tiptronic gearbox: When the selector lever is in position D or S
or in the manual shift programme, the gearbox will remain in 3rd gear if 1st,
2nd or 3rd gears were engaged when the fault occurred. The gearbox will
remain in 5th gear if 4th, 5th or 6th gears were engaged. The gearbox will
then engage 3rd gear when you drive away from a standstill or after the en-
gine is restarted. It will still be possible to use reverse gear in the normal way. However, the
electronic lock for reverse gear will be switched off.
CAUTION
Should the gearbox ever switch into the back-up programme, you should
take the vehicle to a technical service or specialised workshop as soon as
possible.
Steering wheel with paddle levers
The paddle levers on the steering wheel enable the driver to
manually select pre-programmed ratios or gears.
Fig. 152 Steering wheel:
tiptronic controls
– Briefly pull the left-hand paddle lever –
to change down to a
lower gear.
– Briefly pull the right-hand paddle lever +
to change up to a
higher gear.
188Intelligent technology
Practical Tips
Intelligent technology
Electronic Stability Control (ESC)
General Observations
The Electronic Stability Control increases the vehicle's stabil-
ity on the road.
Fig. 153 Centre console
with ESC switch
The ESC is designed to increase the degree of control in situations where
the vehicle approaches the limits of adhesion, especially when accelerating
and cornering. It reduces the risk of skidding and improves stability in all
road conditions. The system is active across the entire speed range. The anti-lock brake system (ABS), the electronic differential lock (EDL) and
the traction control system (ASR) are all integrated into the Electronic Stabil-
ity Control.
How it works
The ESC control unit processes data from the three integrated systems. It al-
so processes additional inputs provided by other high-precision sensors.
These register the vehicle's rotation about the vertical axis (yaw rate), later-
al acceleration, brake pressure and steering wheel angle.
The system uses the steering wheel angle and road speed to calculate the
changes of direction desired 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 vehicle is starting to skid), then the ESC
compensates automatically by braking the appropriate wheel.
The forces acting on the braked wheel bring the vehicle back to a stable
condition. If the vehicle
over swerves (tendency of the rear to leave the
road), the brakes will act on the front wheel facing the outside of the bend.
If the vehicle under swerves (tendency to leave the bend), the braking force
is applied to the rear wheel facing the inside of the bend.
The ESC works in conjunction with the ABS ⇒ page 189. If a malfunction
should occur in the ABS, the ESC will also stop working.
Deactivating
The ESC is activated automatically when the engine is started and performs
a self-test routine.
The ESC cannot be deactivated.
193
Intelligent technology
Brake servo
The brake servo assists the driver when braking
The brake servo increases the pressure you apply to the brake pedal. The
brake servo works only when the engine is running.
WARNING
Ensure the vehicle does not move while in neutral, when the engine is
stopped. Failure to do so could result in an accident.
Note
If the brake servo is not working, e.g. because the vehicle has to be towed
or because it is broken, you will have to press the brake pedal considerably
harder to make up for the lack of servo assistance.
Power steering
Power steering makes it easier to turn the steering wheel
when the engine is running. Power steering assists the driver by reducing the force needed to turn the
steering wheel.
Power steering does not work if the engine is off. In this case the steering
wheel requires much more force to turn.
If the steering is held at its turning limit when the vehicle is stationary, this
will place an excessive load on the power steering system. Turning the
steering wheel to its limit places a load on the system, which causes noise.
It will also reduce the idling speed of the engine.
CAUTION
When the engine is running, do not turn the steering wheel to its limit for
more than 15 seconds. Otherwise, there is a risk of damaging the power
steering.
Note
● If the power steering should fail at any time or the engine is switched off
(for instance when being towed), the vehicle 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 vehicle to a
specialised workshop as soon as possible.
● The power steering system requires a special hydraulic fluid. The fluid
reservoir is located at the front of the engine compartment on the left
⇒ page 297. The correct fluid level in the reservoir is important for the pow-
er steering to function properly. The hydraulic fluid level is checked at the
Inspection Service.
Servotronic*
The servotronic system electronically adjusts the power as-
sisted steering.
In vehicles equipped with servotronic power steering the degree of power
assistance ⇒ page 193 is adjusted
electronically according to road 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), as more effort will be required than usual. The fault
should be corrected by a specialised workshop as soon as possible.
Safety FirstOperating instructionsPractical TipsTechnical Specifications
245
Wheels and tyres
Tyre pressure warning lamp on
When you switch on the ignition, the tyre pressure warning lamp will
light up for about 2 seconds. There is a fault in the system if the indicator
stays on permanently after switching on the ignition. The instrument panel
also display TMPS (Tyre Pressure Monitoring System). Please contact the
nearest specialised workshop as soon as possible.
The tyre pressure warning lamp lights up if the tyre pressure on one or
more wheels is significantly lower than the tyre pressure setting which was
confirmed by the driver ⇒
.
WARNING
● If the tyre pressure warning lamp lights up you must slow down
immediately and avoid any severe braking or steering manoeuvres. Stop
the vehicle as soon as possible and check the tyres and their pressure.
● The driver is responsible for maintaining correct tyre pressures.
Therefore, the tyre pressure must be regularly checked.
● Under certain conditions (e.g. driving at high speeds, on ice and snow
or on poor road surfaces) the tyre pressure warning lamp may not light
up immediately or not at all.
● Please ask your Technical Service or specialised workshop whether
run-flat tyres can be used on your vehicle. Fitting this type of tyre in an
undue manner could lead to your driving licence being taken away from
you. Furthermore, it may led to damage to the vehicle or, under certain
circumstances, may cause accidents.
● If you change normal tyres for run-flat tyres or vice versa, the control
unit must be reprogrammed by the Technical Service or a specialised
workshop.
Note
If you did not press the button for the tyre pressure monitoring system to
confirm a new tyre pressure setting after making changes to the tyre pres-
sures or changing one or more wheels, the warning lamp may light up
although the tyre pressures are correct. In this case, stop the vehicle as
soon as possible and, after examining the tyres, press the button for the
tyre pressure monitoring system.
Safety FirstOperating instructionsPractical TipsTechnical Specifications
247
Wheels and tyres
Wheel balance
The wheels on new vehicles are balanced. However, various factors encoun-
tered in normal driving can cause them to become unbalanced, which re-
sults in steering vibration.
Unbalanced wheels should be rebalanced, as they otherwise cause exces-
sive wear on steering, suspension and tyres. A wheel must also be reba-
lanced when a new tyre is fitted.
Incorrect wheel alignment
Incorrect wheel alignment causes excessive tyre wear, impairing the safety
of the vehicle. If tyres show excessive wear, you should have the wheel
alignment checked by a Technical Service.
WARNING
There is a serious danger of accidents if a tyre bursts during driving!
● The tyres must be replaced at the latest when the tread wear indica-
tors are worn ⇒ page 246. Failure to do so could result in an accident.
Worn tyres do not grip well at high speeds on wet roads. There is also a
greater risk of aquaplaning.
● At continuously high speeds, a tyre with insufficient pressure flexes
more. This causes it to overheat. This can cause tread separation and tyre
blow-out. Risk of accident. Always observe the recommended tyre pres-
sures.
● If tyres show excessive wear, you should have the running gear
checked by a Technical Service.
● Keep chemicals such as oil, fuel and brake fluid away from tyres.
● Damaged wheels and tyres must be replaced immediately!
For the sake of the environment
Under-inflated tyres will increase fuel consumption. Run-flat tyres*
Run-flat tyres allow you to continue driving even with a
punctured tyre, in the majority of cases.
In vehicles that are factory-fitted with run-flat tyres 1)
the loss of tyre
pressure is indicated on the instrument panel.
Driving with run-flat tyres (emergency running)
– Leave the ESC/ASR on (Electronic Stability Control), or switch it
on ⇒ page 69.
– Continue driving carefully and slowly (80 km/h (50 mph) maxi-
mum).
– Avoid sudden manoeuvres and sharp turns.
– Avoid driving over obstacles (for example kerbs) or potholes.
– Pay attention if the ESC/ASR activates often, if smoke comes
from the tyres or there is a smell of rubber, the vehicle vibrates
or there are clattering noises. If any of these occur, stop the ve-
hicle.
The run-flat tyres have a tag on the side of the tyre, with the description:
“DSST”, “Eufonia”, “RFT”, “ROF”, “RSC”, “SSR” or “ZP”.
The sides of this type of tyre are reinforced. When the tyres lose air they are
supported on the sides (emergency driving).
The loss of pressure in the tyre is shown on the instrument panel. You can
then drive a maximum of 80 km (50 miles) and if the circumstances are fa-
vourable (for example, low load), even more.
1)
Depending upon version and country.
Safety FirstOperating instructionsPractical TipsTechnical Specifications