
recognize dangers too late which could result
in an accident and serious injury to you and/
or others.
The ATTENTION ASSIST interprets your
fatigue or increasing inattentiveness
considering the following criteria:
Rthe individual driving style, for example the
way you steer
Rthe driving conditions such as time of day
and duration of the ride
The ATTENTION ASSIST function is restricted
and warnings will be delayed or not issued at
all when
Rroad conditions are bad, e.g. heavy bumps
or potholes
Rcrosswinds are strong
Rdriving in a sporty manner with high speed
in curves or rapid acceleration
Rdriving slower than 50 mph (80 km/h) or
faster than 112 mph (180 km/h) most of
the time
Roperating the COMAND or making phone
calls via COMAND
Rchanging lanes or varying the vehicle
speed, i.e. you intervene actively
Warnings and displays in the
multifunction display
Example illustration
XSwitch on the ATTENTION ASSIST via the
control system (Y page 138).
ATTENTION ASSIST indicator : appears in
the multifunction display.
When the ATTENTION ASSIST is active, it will
warn you after 20 minutes of driving at the
earliest. An intermittent warning will then
sound twice and the message Attention
Assist: Time for a rest? appears in the
multifunction display.
XIf possible park your vehicle in a safe
location and take a rest.
XConfirm the message by pressing button
a on the multifunction steering wheel.
If you do not take a rest and the
ATTENTION ASSIST continues to recognize
fatigue or increasing inattentiveness, you will
be warned once more after 15 minutes at the
earliest.
During long trips, take regular and duly rests
that allow you to recover sufficiently.
The ATTENTION ASSIST will be reset and
restarts evaluating the degree of your fatigue
when
Ryou turn off the engine
Ryou release the seat belt and open the
driver’s door, e.g. during a rest or for a
driver change
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pressure displayed by the control system
apply to sea level. In high-altitude
locations, the reading on a tire pressure
gauge will be higher than the reading issued
by the vehicle’s control system. Do not
reduce the tire inflation pressure under
such circumstances.
XSwitch on the ignition.XPress button = or ; on the
multifunction steering wheel to select the
Serv. menu (Y page 138).
XPress button 9 or : to select Tire
Pressure.
XPress button a.
The current inflation pressure for each tire
appears in the multifunction display.
Example illustration
When the vehicle has been parked for longer
than 20 minutes, the message Tire
pressures will be displayed after
driving a few minutes appears in the
multifunction display.
The TPMS recognizes new wheels or sensors
automatically after the learn-in phase. As long
as the tire inflation pressure values cannot be
allocated to the individual wheels, the
message Tire Pressure Monitor Active
appears. Despite this message, the tire
inflation pressure values are monitored
already.
iWith a spare wheel mounted, the system
may still indicate the tire inflation pressure
of the removed road wheel for some
minutes. If this happens, keep in mind that
the indicated value where the spare wheel
is mounted does not reflect the actual
spare tire inflation pressure.
iOperating radio transmission equipment
(e.g. wireless headsets, two-way radios) in
or near the vehicle could cause the TPMS
to malfunction.
iUSA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause harmful
interference, and
2. this device must accept any
interference received, including
interference that may cause undesired.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
iCanada only:
This device complies with RSS-210 of
Industry Canada. Operation is subject to
the following two conditions:
1.This device may not cause interference,
and
2. this device must accept any
interference received, including
interference that may cause undesired
operation of the device.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
Tire inflation pressure warnings
If the system detects a significant loss of tire
inflation pressure in one or more than one
tire, a message appears in the multifunction
display. In addition, an acoustic warning
sounds and the low tire pressure telltale in the
instrument cluster comes on.
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When using the engine’s braking power, a
drive wheel may not spin for an extended
period of time, e.g. on slippery road
surfaces. This may cause serious damage
to the drivetrain which is not covered by the
Mercedes-Benz Limited Warranty.
Continuous or hard brakingGWarning!
Resting your foot on the brake pedal will
cause excessive and premature wear of the
brake pads.
It can also result in the brakes overheating,
thereby significantly reducing their
effectiveness. It may not be possible to stop
the vehicle in sufficient time to avoid an
accident.
After hard braking, it is advisable to drive on
for some time, rather than immediately park,
so that the air stream will cool down the
brakes faster.
Wet roads
GWarning!
After driving in heavy rain for some time
without applying the brakes or through water
deep enough to wet brake components, the
first braking action may be somewhat
reduced and increased pedal pressure may be
necessary to obtain expected brake effect.
Maintain a safe distance from vehicles in
front.
To help prevent brake disk corrosion after
driving on wet or salt-covered roads, it is
advisable to brake the vehicle with
considerable force prior to parking. The heat
generated serves to dry the brakes.
Salt-covered roads
GWarning!
A layer of salt on the brake discs and the brake
linings may cause a delay in the braking
effect, resulting in a significantly increased
braking distance, which could lead to an
accident.
To avoid this danger, you should:
R occasionally brake carefully when you are
driving on salt-covered roads, so that any
layer of salt that may have built up on the
brake discs and the brake linings is
removed without putting other road users
at risk
R maintain a greater distance to the vehicle
ahead and drive with particular care
R carefully apply the brakes at the end of a
trip and immediately after commencing a
new trip, so that salt residues are removed
from the brake disc
Brake service
! The brake fluid level in the reservoir may
be too low if the red brake warning lamp in
the instrument cluster comes on while the
engine is running and an acoustic warning
sounds. Observe additional messages in
the multifunction display that may appear.
Brake pad wear or a leak in the system may
be the reason for low brake fluid in the
reservoir.
Have the brake system inspected
immediately. Contact an authorized
Mercedes-Benz Center.
All checks and service work on the brake
system should be carried out by qualified
technicians only. Contact an authorized
Mercedes-Benz Center.
Only install brake pads and use brake fluid
recommended by Mercedes-Benz.
GWarning!
If other than recommended brake pads are
installed, or other than recommended brake
fluid is used, the braking properties of the
vehicle can be degraded to an extent that safe
braking is substantially impaired. This could
result in an accident.
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Clearing the maintenance service
indicator message
The maintenance service indicator message
is cleared automatically
R after approximately 10 seconds when you
switch on the ignition
R after approximately 10 seconds when
reaching the service threshold while driving
R after approximately 30 seconds, once the
suggested maintenance service term has
passed
XClearing the maintenance service
indicator message manually: Press
button % or button a on the
multifunction steering wheel.
The standard display appears in the
multifunction display.
Maintenance service term exceeded
If you have exceeded the suggested
maintenance service term, you will see the
following message in the multifunction
display:
Service A Exceeded by XXXXX miles
(km)
Service A Exceeded by XXX days
In addition, a signal sounds when the
message appears.
Any authorized Mercedes-Benz Center will
reset the maintenance service indicator
following a completed maintenance service.
Calling up the maintenance service
indicator display
i The menu overview can be found on
( Y page 129).
You can call up the maintenance service
indicator display at any time to check when
the next maintenance service is required.
XSwitch on the ignition.
The standard display of the control system
appears ( Y page 129).XPress button = or ; on the
multifunction steering wheel to select the
Serv. menu.XPress button : or 9 to select
ASSYST PLUS .XPress button a on the multifunction
steering wheel to confirm.
The maintenance service indicator display
with the maintenance service deadline
appears in the multifunction display.
i If the battery was disconnected, the days
of disconnection will not be included in the
count shown by the maintenance service
indicator. To arrive at the true maintenance
service deadline, you will need to subtract
these days from the days shown in the
maintenance service indicator message or
maintenance service indicator display.
Resetting the maintenance service
indicator
In the event that the maintenance service on
your vehicle is not carried out at an authorized
Mercedes-Benz Center, you can have the
maintenance service indicator reset.
The automotive maintenance facility carrying
out the maintenance service will find the
information for resetting the maintenance
service indicator in the maintenance-relevant
literature for your vehicle.
Such literature is available at any authorized
Mercedes-Benz Center or directly from
Mercedes-Benz.
! If the maintenance service indicator was
reset inadvertently, have an authorized
Mercedes-Benz Center correct it.
Only reset the maintenance service
indicator if the proper maintenance service
has been performed. Not following the
proper maintenance service as described
in the Maintenance Booklet will result in
Maintenance259Operation212_AKB; 2; 41, en-USd2ureepe,Version: 2.11.8.12009-07-17T09:14:21+02:00 - Seite 259Z

Display messagesPossible causes/consequences and M SolutionsCheck
Child
Seat
PositionSee
Operator's
ManualVehicles with BabySmart™ (Canada only):
The BabySmart™ child seat is not positioned correctly.
Risk of injury!XInstall the BabySmart™ child seat in correct position.Vehicles with BabySmart™ (Canada only):
The sensor for child seat recognition is malfunctioning.
Risk of injury!XContact an authorized Mercedes-Benz Center.GWarning!
If the 45 indicator lamp remains illuminated with an adult occupant on the front passenger
seat even after performing the above corrective steps, do not have any passenger use the front
passenger seat until the system has been repaired.
Driving systems
Display messagesPossible causes/consequences and M SolutionsCruise
ControlInoperativ
eThe cruise control is malfunctioning.
In addition an acoustic warning sounds.XHave the cruise control checked at an authorized
Mercedes-Benz Center.Cruise
Control- - - mphOne of the activation conditions for cruise control has not
been fulfilled. You may have attempted to set a speed below
20 mph (30 km/h).XDrive faster than 20 mph (30 km/h) if the situation allows
and set the speed.XCheck the activation conditions for cruise control
( Y page 147).Vehicle status messages in the multifunction display279Practical hints212_AKB; 2; 41, en-USd2ureepe,Version: 2.11.8.12009-07-17T09:14:21+02:00 - Seite 279Z

Display messagesPossible causes/consequences and M SolutionsLane
Keeping
AssistCurrently
Unavailabl
e See
Operator's
ManualThe Lane Keeping Assist is temporarily unavailable.
The Lane Keeping Assist is deactivated because:
R the windshield in front of the camera is dirty
R its function is impaired as a result of heavy precipitation or
fog
R lane markings are not present for an extended period of
time
R lane markings are worn, dark, or covered by dirt or snow
for example
The Lane Keeping Assist becomes operational again and the
message in the multifunction display disappears when:
R dirt on the windshield has fallen off while driving (e.g. slush
or snow)
R the system recognizes full camera availabilityXIf necessary, clean the windshield in front of the camera
( Y page 264).Lane
Keeping
AssistInoperativ
eThe Lane Keeping Assist is malfunctioning.XContact an authorized Mercedes-Benz Center.
Vehicle
Display messagesPossible causes/consequences and M SolutionsApply
Braketo Shift
from 'P'You have attempted to shift the automatic transmission into
drive position D, reverse gear R or neutral position N without
depressing the brake pedal.XDepress the brake pedal.Door OpenVehicle
Not in 'P'In addition an acoustic warning sounds.
You have opened the driver’s door and the automatic
transmission is still in drive position D, reverse gear R or
neutral position N.XBefore you leave the vehicle, make sure the automatic
transmission is in park position P and the parking brake is
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Display messagesPossible causes/consequences and M SolutionsService
RequiredDo Not
Shift
Gears
Visit
DealerIn addition an acoustic warning sounds.
The automatic transmission cannot be shifted out of the
current transmission position because of a malfunction.
If the automatic transmission is in drive position D:XWithout shifting the automatic transmission out of drive
position D, drive to an authorized Mercedes-Benz Center.
If the automatic transmission is set to position neutral
position N, reverse gear R or park position P:
XDo not drive.XContact an authorized Mercedes-Benz Center or call
Roadside Assistance.Only
Shift to
'P' when
Vehicle
is
StationaryYou have attempted to shift the automatic transmission into
park position P although the vehicle was still in motion.XStop your vehicle as soon as it is safe to do so.XShift the automatic transmission to park position P.Shift to
'P' or 'N'to Start
EngineYou have attempted to start the engine with the KEYLESS-GO
start/stop button while the automatic transmission was in
reverse gear R or drive position D.XShift the automatic transmission into park position P or
neutral position N. Make sure the brake pedal is depressed.Auxiliary
BatteryMalfunctio
nThe backup battery for the automatic transmission is no
longer charging.XContact an authorized Mercedes-Benz Center.
Tires
Display messagesPossible causes/consequences and M SolutionsCheck
Tire
PressureThen
Restart
Run Flat
IndicatorThere has been a warning message about a loss in the tire
inflation pressure and the tire pressure loss warning system
was not restarted yet.XMake sure the correct tire inflation pressure is set for each
tire.XThen restart the tire pressure loss warning system
( Y page 232).Run Flat
IndicatorInoperativ
eThe tire pressure loss warning system is malfunctioning.XHave the tire pressure loss warning system checked at an
authorized Mercedes-Benz Center.284Vehicle status messages in the multifunction displayPractical hints
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Display messagesPossible causes/consequences and M Solutions$
(USA only)
J
(Canada
only)EBD, ABS,
and ESC
Inoperativ
e See
Operator's
ManualIn addition, the yellow ESC warning lamp ä, the yellow
ESC OFF warning lamp å, and the yellow ABS indicator
lamp ! come on.
The brake system is still functioning normally but due to a
malfunction, the ABS, the BAS, the BAS PLUS, the EBP, the
ESC, the HOLD function, the PRE-SAFE ®
system, and the PRE-
SAFE ®
Brake are unavailable.
The ATTENTION ASSIST is disabled.XContinue driving with added caution. Wheels may lock
during hard braking, reducing steering capability.XAdjust driving to be consistent with reduced braking
responsiveness.XHave the system checked at an authorized Mercedes-Benz
Center as soon as possible.
Failure to follow these instructions increases the risk of an
accident.
$
(USA only)
!
(Canada
only)Release
Parking
BrakeYou are driving with the parking brake engaged. In addition
an acoustic warning sounds.XRelease the parking brake.$
(USA only)
J
(Canada
only)Check
Brake
Fluid
LevelThere is insufficient brake fluid in the reservoir.
Risk of accident!XStop the vehicle in a safe location or as soon as it is safe
to do so.XEngage the parking brake.XDo not drive any further.XContact an authorized Mercedes-Benz Center or call
Roadside Assistance.
Do not add brake fluid! This will not solve the problem.
GWarning!
Driving with the message Check Brake Fluid Level displayed can result in an accident. Have
your brake system checked immediately.
Do not add brake fluid before checking the brake system. Overfilling the brake fluid reservoir can
result in spilling brake fluid on hot engine parts and the brake fluid catching fire. You can be
seriously burned.
! If you find that the brake fluid in the brake fluid reservoir has fallen to the minimum mark
or below, have the brake system checked for brake pad thickness and leaks.
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