172Driving and operatingDeactivation
The system can be deactivated.
Press V repeatedly until the following
message appears in the Driver
Information Centre.
General information for both
variants of forward collision alert
9 Warning
Forward collision alert is just a
warning system and does not
apply the brakes. When
approaching a vehicle ahead too
rapidly, it may not provide you
enough time to avoid a collision.
The driver accepts full
responsibility for the appropriate
following distance based on traffic, weather and visibility conditions.
The complete attention of the
driver is always required while
driving. The driver must always be
ready to take action and apply the
brakes.
System limitations
The system is designed to warn only for vehicles, but may react also to
other metallic objects.
In the following cases, forward
collision alert may not detect a vehicle ahead or sensor performance is
limited:
● on winding roads
● when weather limits visibility, e.g.
fog, rain, or snow
● when the sensor is blocked by snow, ice, slush, mud, dirt, or
windscreen damage
Following distance
indication
The following distance indication
displays the distance to a preceding
moving vehicle. The system uses,
depending on the vehicle equipment,
either the radar behind the radiator
grille or the front camera in the
windscreen to detect the distance of
a vehicle directly ahead in your path.
It is active at speeds above 40 km/h.
When a preceding vehicle is detected
ahead, the distance is indicated in
seconds, displayed on a page in the
Driver Information Centre 3 93 . Press
MENU on the turn signal lever to
select Vehicle Information Menu
X and turn the adjuster wheel to
choose following distance indication
page.
Driving and operating173
The minimum indicated distance is
0.5 s.
If there is no vehicle ahead or the vehicle ahead is out of range, two
dashes will be displayed: -.- s.
Active Emergency Braking
Active emergency braking can help to reduce the damage from crashes with vehicles and obstacles directly
ahead, when a collision can no longer be avoided either by manual braking
or by steering. Before the active
emergency braking applies, the driver
is warned by the forward collision
alert 3 169.
The feature uses various inputs (e.g.
radar sensor, brake pressure, vehicle speed) to calculate the probability of
a frontal collision.
Active emergency braking operates automatically above walking speed,
provided that Auto collision
preparation setting is not deactivated
in the vehicle personalisation menu
3 105.
The system includes: ● brake preparation system
● emergency automatic braking
● forward looking brake assist9Warning
This system is not intended to
replace the driver responsibility of driving the vehicle and looking
ahead. Its function is limited to
supplemental use only. The driver shall continue to apply the brake
pedal as the driving situation
dictates.
Brake preparation system
When approaching a vehicle ahead
so quickly that a collision is likely, the
brake preparation system slightly
pressurises the brakes. This reduces
the response time, when a manual or automatic braking is requested.
The brake system is prepared so that braking can occur more rapidly.
Emergency automatic braking
After the brake preparation and just
before the imminent collision, this
function automatically applies limited
braking to reduce the impact speed of the collision.
Forward looking brake assist
In addition to brake preparation
system and emergency automatic
braking, the forward looking brake
assist function makes the brake assist more sensitive. In this way,
depressing the brake pedal slightly
results immediately in a strong
braking. This function helps the driver
brake quicker and stronger before the imminent collision.
174Driving and operating9Warning
Active emergency braking is not
designed to apply strong
autonomous braking or to avoid automatically a collision. It is
designed to reduce the vehicle
speed before collision. It may not
react on stopped vehicles,
pedestrians or animals. After a
sudden lane change, the system
needs a certain time to detect the
next preceding vehicle.
The complete attention of the
driver is always required while
driving. The driver shall always be ready to take action and apply the brakes and steer to avoid
collisions. The system is designed
to work with all occupants wearing their seat belts.
System limitations
The active emergency braking has
limited or no function during rain,
snow or heavy dirt, as the radar
sensor can be covered by a water
film, dust, ice or snow. In case of
sensor blockage, clean the sensor
cover.
In some seldom cases the active
emergency braking system may
provide a short automatic braking in
situations that seem to be
unnecessary, for instance due to
traffic signs in a curve or due to
vehicles in another lane. This is
acceptable operation, the vehicle
does not need service. Firmly apply
the accelerator pedal to override the
automatic braking.
Settings
Settings can be changed in the Auto
collision preparation menu in the
vehicle personalisation, 3 105.
Fault
In the event of a system service
requirement, a message is displayed
in the Driver Information Centre.
If the system does not work as it
should do, vehicle messages are
displayed in the Driver Information
Centre.
Vehicle messages 3 99.
Vehicle care225No.Circuit16Starter17Transmission control module18Heated rear window19Front power windows20Rear power windows21Rear electrical centre22Left high beam (Halogen)23Headlamp washer system24Right low beam (Xenon)25Left low beam (Xenon)26Front fog lights27Diesel fuel heating28Start stop system29Electric parking brake30ABS31Adaptive cruise control32AirbagNo.Circuit33Adaptive forward lighting/Auto‐
matic light control34Exhaust gas recirculation35Exterior mirror/Rain sensor36Climate control37Canister vent solenoid38Vacuum pump39Central control module40Windscreen washer/Rear
window washer system41Right high beam (Halogen)42Radiator fan43Windscreen wiper44Windscreen wiper45Radiator fan46–47Horn48Radiator fanNo.Circuit49Fuel pump50Headlamp levelling/Adaptive
forward lighting51Air shutter52Auxiliary heater/Diesel engine53Transmission control module/
Engine control module54Vacuum pump/Instrument
panel cluster/Heating ventila‐
tion/Air conditioning system
After having changed defective fuses,
close the fuse box cover and press
until it engages.
If the fuse box cover is not closed
correctly, malfunction may occur.
Vehicle care233
A detected low tyre pressure
condition is indicated by illumination
of control indicator w 3 91.
If w illuminates, stop as soon as
possible and inflate the tyres as
recommended 3 271.
If w flashes for 60-90 seconds and
then illuminates continuously, there is
a fault in the system. Consult a
workshop.
After inflating, driving may be
required to update the tyre pressure
values in the Driver Information
Centre. During this time w may
illuminate.
If w illuminates at lower temperatures
and extinguishes after some driving,
this could be an indicator for
approaching a low tyre pressure
condition. Check tyre pressure.
Vehicle messages 3 99.
If the tyre pressure must be reduced
or increased, switch off ignition.
Only mount wheels with pressure
sensors, otherwise the tyre pressure
will not be displayed and w
illuminates continuously.
A spare wheel or temporary spare
wheel is not equipped with pressure
sensors. The tyre pressure
monitoring system is not operational
for these wheels. Control indicator w
illuminates. For the further three
wheels the system remains
operational.
The use of commercially available
liquid tyre repair kits can impair the
function of the system. Factory-
approved repair kits can be used.
Operating electronic devices or being close to facilities using similar wave
frequencies could disrupt the tyre
pressure monitoring system.Each time the tyres are replaced, tyre pressure monitoring system sensors
must be dismounted and serviced. For the screwed sensor: replace
valve core and sealing ring. For
clipped sensor: replace complete
valve stem.
Vehicle loading status Adjust tyre pressure to load condition
according to the tyre information label or tyre pressure chart 3 271, and
select the appropriate setting in the Tyre load menu in the Driver
Information Centre 3 93. This setting
is the reference for the tyre pressure
warnings.
The Tyre Load menu only appears if
the vehicle is in a standstill and the
parking brake is applied. On vehicles
with automatic transmission, the
selector lever must be in P.
234Vehicle care
Select:● Light for comfort pressure up to
3 people.
● Eco for Eco pressure up to
3 people.
● Max for full load.
Tyre pressure sensor matching
process
Each tyre pressure sensor has a
unique identification code. The
identification code must be matched
to a new wheel position after rotating the wheels or exchanging the
complete wheel set and if one or more
tyre pressure sensors were replaced.
The tyre pressure sensor matching
process should also be performed
after replacing a spare wheel with a
road wheel containing the tyre
pressure sensor.
The malfunction light w and the
warning message or code should
extinguish at the next ignition cycle.
The sensors are matched to the
wheel positions using a relearn tool,
in the following order: left side front
wheel, right side front wheel, right
side rear wheel and left side rear
wheel. The turn signal light at the
current active position is illuminated
until the sensor is matched.
Consult a workshop for service. There
are two minutes to match the first
wheel position, and five minutes
overall to match all four wheel
positions. If it takes longer, the
matching process stops and must be
restarted.
The tyre pressure sensor matching
process is:
1. Apply the parking brake.
2. Turn the ignition on.3. On vehicles with automatic transmission: set the selector
lever to P.
On vehicles with manual
transmission: select neutral.
4. Use MENU on the turn signal
lever to select the Vehicle
Information Menu in the Driver
Information Centre.
5. Turn the adjuster wheel to scroll to
the tyre pressure menu.
6. Press SET/CLR to begin the
sensor matching process. A
message requesting acceptance
of the process should be
displayed.
Press SET/CLR again to confirm
the selection. The horn sounds
twice to indicate the receiver is in
relearn mode.
7. Start with the left side front wheel.
8. Place the relearn tool against the tyre sidewall, near the valve stem.Then press the button to activate
the tyre pressure sensor. A horn
chirp confirms that the sensor
identification code has been
matched to this wheel position.