
Problems with fuel and the fuel tank
Problem Possible causes/consequences and
0001 Solutions
Fuel is leaking from the
vehicle. The fuel line or the fuel tank is faulty.
G WARNING
Risk of explosion or fire.
X Turn the SmartKey to position 0in the ignition lock and remove
it immediately (Y page 165).
X Do not restart the engine under any circumstances.
X Consult a qualified specialist workshop. The fuel filler flap
cannot be opened. The fuel filler flap is not unlocked.
or
The SmartKey battery is discharged.
X
Unlock the vehicle (Y page 82).
or
X Unlock the vehicle using the mechanical key (Y page 84).The fuel filler flap is unlocked, but the opening mechanism is
jammed.
X
Consult a qualified specialist workshop. Parking
Important safety notes
G
WARNING
Flammable material such as leaves, grass or
twigs may ignite if they come into contact with
hot parts of the exhaust system or exhaust
gas flow. There is a risk of fire.
Park the vehicle so that no flammable
materials come into contact with parts of the
vehicle which are hot. Take particular care not
to park on dry grassland or harvested grain
fields. G
WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect,
for example, the power steering and the brake
boosting effect.Y ou will require considerably more effort to steer and brake. There is a risk
of an accident.
Do not switch off the ignition while driving.
G
WARNING
If you leave children unsupervised in the
vehicle, they could set it in motion by, for
example:
R releasing the parking brake
R shifting the automatic transmission out of
the parking position P
R starting the engine.
They could also operate the vehicle's
equipment. There is a risk of an accident and
injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle. 182
ParkingDriving and parking

X
To apply: depress parking brake 0003firmly.
Whe nthe engine is running, the 000B(USA
only) or 0005(Canada only) indicator lamp
lights up in the instrumentc luster.
X To release: depress the brake pedal and
keep it depressed.
X Pull release handle 0002.
When the ignition is switched on or the
engine is running, the 000B(USA only) or
0005 (Canada only) indicator lamp goes out
in the instrument cluster. Parking the vehicle for
along period
If you leave the vehicle parked for longer than
four weeks, the battery may be damaged by
exhaustive discharging.
If you leave the vehicle parked for longer than
six weeks, the vehicle may suffer damage as
a result of lack of use.
X Visit a qualified specialist workshop and
seek advice.
i You can obtain information about trickle
chargers from a qualified specialist
workshop. Driving tips
General notes
Important safety notes G
WARNING
If you switch off the ignitio nwhile driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect,
for example, the power steering and the brake
boosting effect.Y ou will require considerably
more effort to steer and brake. There is a risk
of an accident.
Do not switch off the ignition while driving. G
WARNING
If you operate mobile communication
equipment while driving, you will be distracted from traffic conditions. You could
also lose control of the vehicle. There is a risk
of an accident.
Only operate this equipment when the vehicle
is stationary.
Observe the legal requirements for the
country in which you are driving. Some
jurisdictions prohibit the driver from using a
mobile phone while driving a vehicle.
If you make a call while driving, always use
hands-free mode. Only operate the telephone
when the traffic situation permits. If you are
unsure, pull over to a safe location and stop
before operating the telephone.
Bear in mind that at a speed of only 30 mph
(approximately 50 km/h), the vehicle covers
a distance of 44 ft (approximately 14 m) per
second.
Drive sensibly –save fuel Observe the following tips to save fuel:
X
The tires should always be inflated to the
recommended tire pressure.
X Remove unnecessary loads.
X Remove roof racks whe nthey are not
needed.
X Warm up the engine at low engine speeds.
X Avoid frequent acceleration or braking.
X Have all maintenance work carried out as
indicated by the service intervals in the
Maintenance Booklet or by the service
interval display.
Fuel consumption also increases when
driving in cold weather, in stop-start traffic
and in hilly terrain.
Drinking and driving G
WARNING
Drinking and driving and/or taking drugs and
driving are very dangerous combinations.
Even a small amount of alcohol or drugs can
affect your reflexes, perceptions and
judgment. 184
Driving tipsDriving and parking

If the vehicle threatens to skid or cannot be
stopped when moving at low speed:
X Shift the transmission to position N.
Drive particularly carefully on slippery road
surfaces .Avoid sudden acceleration, steering
and braking maneuvers. Do not use the cruise
control or DISTRONIC PLUS.
i For more information on driving with
snow chains, see (Y page 347).
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
Changes in the outside temperature are
displayed after a short delay.
Indicated temperatures just above the
freezing point do not guarantee that the road
surface is free of ice. The road may still be icy,
especially in wooded areas or on bridges. The
vehicle could skid if you fail to adapt your
driving style .Always adapt your driving style
and drive at a speed to suit the prevailing
weathe rconditions.
You should pay special attention to road
conditions when temperatures are around
freezing point. Driving systems
Cruise control
General notes Cruise control maintains a constant road
speed for you. It brakes automatically in order
to avoid exceeding the set speed. On long and
steep downhill gradients, especially if the
vehicle is laden, you must shift to a lower gear
in time. By doing so, you will make use of the
braking effect of the engine. This relieves the
load on the brake system and prevents the
brakes from overheating and wearing too
quickly.
Use cruise control only if road and traffic
conditions make it appropriate to maintain a
steady speed for a prolonged period. You can store any road speed above 20 mph
(30 km/h).
Important safety notes If you fail to adapt your driving style, cruise
control can neither reduce the risk of an
accident nor override the laws of physics.
Cruise control cannot take into account the
road, traffic and weather conditions. Cruise
control is only an aid. You are responsible for
the distance to the vehicle in front, for vehicle
speed, for braking in good time and for
staying in your lane.
Do not use cruise control:
R
in road and traffic conditions which do not
allow you to maintain a constant speed e.g.
in heavy traffic or on winding roads
R on slippery road surfaces. Braking or
accelerating could cause the drive wheels
to lose traction and the vehicle could then
skid
R when there is poor visibility, e.g. due to fog,
heavy rain or snow
If there is a change of drivers, advise the new
driver of the speed stored.
Cruise control lever 0002
To activate or increase speed
0003 To activate or reduce speed
0023 To deactivate cruise control
0022 To activate at the current speed/last
stored speed Driving systems
189Driving and parking Z

DISTRONIC PLUS wit
hSteering Assist General notes
DISTRONIC PLU
SSteering Assist aids you in
keeping the vehicle in the cente rofthe driving
lane by means of moderate steering
interventions at speeds of 0 - 125 mph
(0 - 200 km/h).
DISTRONIC PLUS Steering Assist monitors
the area in front of your vehicle by means of
camera system 0002, at the top of the
windshield.
At speeds of more than 37 mph (60 km/h)
DISTRONIC PLUS Steering Assist focuses on
lane markings that are present.
At speeds of 0 - 37 mph (0 - 60 km/h)
DISTRONIC PLUS Steering Assist focuses on
the vehicle in front, taking into account lane
markings, e.g. when following vehicles in a
traffic jam.
DISTRONIC PLUS must be active in order for
the Steering Assist function to be available.
Important safety notes
If you fail to adapt your driving style,
DISTRONIC PLUS SteeringA ssist can neither
reduce the risk of an accident nor override the
laws of physics. DISTRONIC PLUS Steering
Assist cannot take into account road,
weather or traffic conditions. DISTRONIC
PLUS Steering Assist is only an aid. You are
responsible for the distance to the vehicle in
front, for vehicle speed, for braking in good
time and for staying in your lane.
DISTRONIC PLUS Steering Assist does not
detect road and traffic conditions. If you are following a vehicle which is driving towards
the edge of the road, your vehicle could come
into contact with the curb or other road
boundaries. In the case of deviations in road
markings, beware of other road users, e.g.
cyclists, that are in the direct vicinity of your
vehicle.
Obstacles such as building site huts on the
lane or projecting out into the lane are not
detected.
An inappropriate steering intervention, e.g.
after intentionally driving over a lane marking,
can be corrected at any time if you steer
slightly in the opposite direction.
DISTRONIC PLUS Steering Assist cannot
continuously keep your vehicle in lane. In
some cases, the steering intervention is not
sufficient to bring the vehicle back to the lane.
In such cases, you must steer the vehicle
yourselft
o ensure that it does not leave the
lane.
The system may be impaired or may not
function if:
R there is poor visibility, e.g. due to
insufficient illumination of the road, or due
to snow, rain, fog or spray
R there is glare, e.g. from oncoming traffic,
the sun or reflections (e.g. when the road
surface is wet)
R the windshield is dirty, fogged up, damaged
or covered, for instance by a sticker, in the
vicinity of the camera
R no, or several, unclear lane markings are
present for one lane, e.g. in a construction
area
R the lane markings are worn away, dark or
covered up, e.g. by dirt or snow
R the distance to the vehicle in front is too
small and the lane markings thus cannot be
detected
R the lane markings change quickly, e.g.
lanes branch off, cross one another or
merge
R the road is narrow and winding
R there are strong shadows cast on the lane 200
Driving systemsDriving and parking

Pay attention also to the importan
tsafety
notes for DISTRONIC PLUS (Y page 192).
The steering interventions are carried out
with a limited steering moment. The system
requires the driver to keep his hands on the
steering wheel and to steer himself.
If you do no tstee ryourself or if take your
hands off the steering wheel for a prolonged
period of time, the system will first alert you
with a visual warning. Asteering wheel
symbol appears in the multifunctio ndisplay.
If you have still not started to steer and have
not taken hold of the steering wheel after five
seconds, a warning tone also sounds to
remind you to take control of the vehicle.
DISTRONIC PLUS Steering Assist is then
switched to passive .DISTRONIC PLUS
remains active.
The system is switched to passive and no
longer assists you by performing steering
interventions if:
R you actively change lanes
R you switch on the turn signal
R take yourh ands off the steering wheel or
do no tstee rfor a prolonged period of time
i After you have finished changing lanes,
DISTRONIC PLUS Steering Assist is
automatically active once more.
DISTRONIC PLUS Steering Assist does not
provide assistance:
R on very sharp corners
R if no lane markings or no clear lane
markings have been detected
R if the vehicle in front is not detected at
speeds below 37 mph (60 km/h)
R in tire run-flat mode
Activating Steering Assist
X Select the DISTRONIC PLUS with Steering
Assist function using the on-board
computer (Y page 242).
The DTR+: Steering Assistant On message appears in the multifunction
display .DISTRONIC PLUS Steering Assist
is activated. Information in the multifunction display
If DISTRONIC PLUS Steering Assist is
activated but is not ready for a steering
intervention, steering wheels
ymbol0002
appears in grey. If th esystem provides you
with suppor tby means of steering
interventions, symbol 0002is shown in green.
Deactivating Steering Assist
X Deactivate the DISTRONIC PLUS with
Steering Assis tfunction using the on-board
computer (Y page 242).
The DTR+ Steering Assistant Off message appears in the multifunction
display. DISTRONIC PLU
SSteering Assist
is deactivated.
When DISTRONIC PLU Sis deactivated,
DISTRONIC PLUS Steering Assist is
deactivated automatically. HOLD function
General notes The HOLD function can assist the driver in the
following situations:
R
when pulling away, especially on steep
slopes
R when maneuvering on steep slopes
R when waiting in traffic
The vehicle is kept stationary without the
driver having to depress the brake pedal.
The braking effect is canceled and the HOLD
function deactivated when you depress the
accelerator pedal to pull away. Driving systems
201Driving and parking Z

Problems with PARKTRONIC
Problem Possible causes/consequences and
0001 Solutions
Only the red segments
in the PARKTRONIC
warning displays are lit.
You also hear a warning
tone for approximately
two seconds.
PARKTRONIC is then
deactivated and the
indicator lamp on the
PARKTRONIC button
lights up. PARKTRONIC has malfunctioned and has switched off.
X
If problems persist, have PARKTRONIC checked at a qualified
specialist workshop. Only the red segments
in the PARKTRONIC
warning displays are lit.
PARKTRONIC is then
deactivated. The PARKTRONIC sensors are dirty or there is interference.
X
Cleant he PARKTRONIC sensors (Y page 323).
X Switch the ignition back on. The problem may be caused by an external source of radio or
ultrasound waves.
X See if PARKTRONIC functions in a different location. Active Parking Assist
General notes Active Parking Assist is an electronic parking
aid with ultrasound. It measures the road on
both sides of the vehicle. Aparking symbol
indicates a suitable parking space. Active
steering interventio nand brake application
can assist you during parking .You may also
use PARKTRONIC (Y page 204).
Important safety notes Active Parking Assist is merely an aid. It is not
a replacement for your attention to your
immediate surroundings. You are always
responsible for safe maneuvering, parking
and exiting a parking space. Make sure that
no persons, animals or objects are in the
maneuvering range.
When PARKTRONIC is switched off, Active
Parking Assist is also unavailable. G
WARNING
While parking or pulling out of a parking
space, the vehicle swings out and can drive
onto areas of the oncoming lane. This could
result in a collision with another road user.
There is a risk of an accident.
Pay attention to other road users. Stop the
vehicle if necessary or cancel the Active
Parking Assist parking procedure.
! If unavoidable, you should drive over
obstacles such as curbs slowly and not at
a sharp angle. Otherwise, you may damage
the wheels or tires.
Active Parking Assist may possibly indicate
parking spaces which are not suitable for
parking, for example:
R where parking or stopping is prohibited
R in front of driveways or entrances and exits
R on unsuitable surfaces Driving systems
207Driving and parking Z

Parking tips:
R
On narrow roads, drive as close to the
parking space as possible.
R Parking spaces that are littered or
overgrown might be identified or measured
incorrectly.
R Parking spaces that are partially occupied
by trailer drawbars might not be identified
as such or be measured incorrectly.
R Snowfall or heavy rain may lead to a parking
space being measured inaccurately.
R Pay attention to the PARKTRONIC
(Y page 205) warning messages during the
parking procedure.
R You can intervene in the steering procedure
to correct it at any time. Active Parking
Assist will then be canceled.
R When transporting a load which protrudes
from your vehicle, you should not use
Active Parking Assist.
R Never use Active Parking Assist when snow
chains are installed.
R Make sure that the tire pressures are
always correct. This has adirec tinfluence
on the parking characteristics of the
vehicle.
Use Active Parking Assist for parking spaces:
R tha tare parallel or at right-angles to the
direction of travel
R that are on straight roads, not bends
R that are on the same level as the road, e.g.
not on the pavement
Detecting parking spaces Objects located above the height range of
Active Parking Assist will not be detected
when the parking space is measured. These
are not taken into account when the parking
procedure is calculated, e.g. overhanging
loads, tail sections or loading ramps of goods
vehicles. G
WARNING
If there are objects above the detection range:
R Active Park Assist may steer too early
R the vehicle may not stop in front of these
objects.
You may cause a collision as a result. There is
a risk of an accident.
If there are objects above the detection range,
stop and deactivate Active Parking Assist.
For further information on the detection
range (Y page 204).
Active Parking Assist does not support you
with parking spaces at right-angles to the
direction of travel if:
R two parking spaces are located directly
next to one another
R the parking space is directly next to a low
obstacle such as a low curb
R you park forwards
Active Parking Assist does not support you
with parking spaces that are parallel or at
right-angles to the direction of travel if:
R the parking space is on acurb
R the system reads the parking space as
being blocked, for example by foliage or
grass paving blocks
R the area is too small for the vehicle to
maneuver into
R the parking space is bordered by an
obstacle, e.g. a tree, a post or a trailer Example: detected parking space
0002 Detected parking space on the left
0003 Parking symbol
0023 Detected parking space on the right 208
Driving systemsDriving and pa
rking

Active Parking Assist is switched on
automatically when driving forwards
.The
system is operational at speeds of up to
approximately 22 mph (35 km/h). While in
operation, the system independently locates
and measures parking spaces on both sides
of the vehicle.
Active Parking Assist will only detect parking
spaces:
R that are parallel or at right-angles to the
direction of travel
R that are parallel to the direction of travel
and at least 59 in (1.5 m) wide
R that are parallel to the direction of travel
and at least 39.5 in (1.0 m) longer than your
vehicle
R that are at right angles to the direction of
travel and at least 39.5 in (1.0 m) wider
than your vehicle
i In the case of parking spaces that are at
right angles to the direction of travel,
please ensure that the parking space is
long enough to accommodate your vehicle.
When driving at speeds below 19 mph
(30 km/h), you will see parking symbol as a
status indicator in the instrument cluster.
When a parking space has been detected, an
arrow towards the right or the left also
appears. By default, Active Parking Assist
only displays parking spaces on the front-
passenger side. Parking spaces on the
driver's side are displayed as soon as the turn
signal on the driver's side is activated. When
parking on the driver's side, this must remain
switched on until you acknowledge the use of
Active Parking Assist by pressing the 000B
button on the multifunction steering wheel.
The system automatically determines
whether the parking space is parallel or at
right-angles to the direction of travel.
Ap arking space is displayed while you are
driving past it, and until you are
approximately 50 ft (15 m) away from it. Parking i
Vehicles with automatic transmission:
When PARKTRONIC detects obstacles,
Active Parking Assist brakes automatically
during the parking process. You are
responsible for braking in good time.
X Stop the vehicle when the parking space
symbol shows the desired parking space in
the instrument cluster.
X Shift the transmission to position R.
The Start Park Assist? Yes: OK No: 0007
message appears in the multifunction
display.
X To cancel the procedure: press the
0007 button on the multifunction steering
wheel or pull away.
or
X To park using Active Parking Assist:
press the 000Bbuttonont he multifunction
steering wheel.
The Park Assist Active Accelerate and Brake Observe Surroundings
message appears in the multifunction
display.
X Let go of the multifunction steering wheel.
X Back up the vehicle, being ready to brake
at all times. When backing up, drive at a
speed below approximately 6mph
(10 km/h). Otherwise Active Parking Assist
will be canceled.
Active Parking Assist brakes the vehicle to
a standstill when the vehicle is in the
parking space.
Maneuvering may be required in tight
parking spaces.
The Park Assist Active Select D Observe Surroundings message appears in
the multifunction display.
X Shift the transmission to position Dwhile
the vehicle is stationary.
Active Parking Assist immediately steers in
the other direction. Driving systems
209Driving and parking Z