Page 194 of 343

192Driving and operating
Deactivation
The system can be deactivated.
Press button 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 3 119.
Press the MENU button on the turn
signal lever to select Vehicle
Information Menu X and turn the
adjuster wheel to choose following
distance indication page.
Page 195 of 343

Driving and operating193
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 3 189.
The feature uses various inputs (e.g.
radar sensor, brake pressure, vehicle speed) to calculate the probability ofa frontal collision.
Active emergency braking operates automatically above walking speed,
provided that Auto collision
preparation setting is not deactivated
in the vehicle personalisation menu
3 132.
The system includes: ■ Brake preparation system
■ Emergency automatic braking
■ Forward looking brake assist9 Warning
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
Page 196 of 343

194Driving and operating
results immediately in a strong
braking. This function helps the driver brake quicker and stronger before theimminent collision.9 Warning
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, 3 132.
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 3 126.
Page 254 of 343

252Vehicle care
No.Circuit15Engine control module16Starter17Transmission 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 controlNo.Circuit32Airbag33Adaptive 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–No.Circuit47Horn48Radiator fan49Fuel 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.
Page 264 of 343

262Vehicle care
matching process should also be
performed after replacing a spare tyre with a road tyre containing the TPMS
sensor.
The malfunction light and the warning
message or code should go off at the
next ignition cycle. The sensors are
matched to the tyre/wheel positions,
using a TPMS relearn tool, in the
following order: left side front tyre,
right side front tyre, right side rear tyre and left side rear tyre. The turn signal
light at the current active position is
illuminated until sensor is matched.
Consult your workshop for service or
to purchase a relearn tool. There are
two minutes to match the first tyre/
wheel position, and five minutes
overall to match all four tyre/wheel
positions. If it takes longer, the
matching process stops and must be
restarted.The TPMS sensor matching process
is:
1. Apply the parking brake; on vehicles with automatic
transmission set the selector lever
to P.
2. Turn the ignition on.
3. Use the MENU button on the turn
signal lever to select the Vehicle
Information Menu in the Driver
Information Centre (DIC).
4. Turn the adjuster wheel to scroll to
the tyre pressure menu.
5. Press the SET/CLR button to
begin the sensor matching
process. A message requesting
acceptance of the process should
display.
6. Press the SET/CLR button again
to confirm the selection. The horn sounds twice to signal the
receiver is in relearn mode.
7. Start with the left side front tyre.
8. Place the relearn tool against the tyre sidewall, near the valve stem.Then press the button to activate
the TPMS sensor. A horn chirpconfirms that the sensor
identification code has been
matched to this tyre and wheel
position.
9. Proceed to the right side front tyre,
and repeat the procedure in Step 8.
10. Proceed to the right side rear tyre,
and repeat the procedure in
Step 8.
11. Proceed to the left side rear tyre, and repeat the procedure in
Step 8. The horn sounds twice to
indicate the sensor identification
code has been matched to the left side rear tyre, and the TPMS
sensor matching process is no
longer active.
12. Turn off the ignition.
13. Set all four tyres to the recommended air pressure level
as indicated on the tyre pressure
label.
14. Ensure the tyre loading status is set according selected pressure
3 119.