Flat tireChanging a wheel/mounting the
spare wheel ................................... 301
MOExtended run-flat system .........307
Preparing the vehicle .....................296
Raising the vehicle .........................303
TIREFIT kit ...................................... 297
Floormat ............................................. 276
Front fog lamp (display
message) ............................................ 223
Fuel Additives ........................................ 353
Notes ............................................. 352
Premium-grade unleaded gasoline . 352
Refueling ........................................ 160
Specifications ................................ 352
Troubleshooting ............................. 164
Fuel consumption
Current (on-board computer) .........211
Notes ............................................. 168
Fuel filler cap (display message) ..... 227
Fuel filler flap Emergency release ........................162
Opening/closing ............................ 162
Fuel filter (display message) ............ 227
Fuel level Calling up the range (on-board
computer) ...................................... 211
Fuses
Dashboard fuse box .......................316
Engine emergency stop .................317
Fuse allocation chart .....................315
Fuse box in the cargo
compartment ................................. 316
Fuse box in the engine
compartment ................................. 316
Notes ............................................. 315
G
Garage door opener Clearing the memory .....................275
Notes ............................................. 272
Opening/closing the garage door ..275
Programming the remote control ...273
Gear or selector lever (cleaning
guidelines) ......................................... 288
Genuine Mercedes-Benz parts ......... 348
Genuine wood trim and trim strips
(cleaning instructions) ...................... 288
Glove box ........................................... 247
GTW (Gross Trailer Weight)
(definition) ......................................... 341
H
Headlamp cleaning system .............. 119
Adding washer fluid .......................281
Notes ............................................. 357
Headlamp delayed switch-off
see Delayed switch-off, exterior lighting
Headlamp mode (daytime driving)
see Daytime running lamps
Headlamps
Cleaning ......................................... 286
Misting up ...................................... 120
Head restraint
Adjusting (electrically) ...................101
Head restraints
Adjusting (manually) ......................101
Adjusting (rear) .............................. 102
Installing/removing (rear) ..............102
Luxury ............................................ 101
see NECK-PRO head restraints/
NECK-PRO luxury head restraints
Heating
see Climate control
High beam flasher ............................. 119
Hill start assist .................................. 152
Hood Closing ........................................... 279
Opening ......................................... 278
Hydroplaning ..................................... 171
I
Immobilizer .......................................... 71
Indicator and warning lamps ABS ................................................ 239
Brakes ........................................... 236
DISTRONIC .................................... 243
Engine diagnostics .........................242
ESP ®
.............................................. 240
Fuel tank ........................................ 242
Reserve fuel ................................... 242
Seat belt ........................................ 237
Index9BA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 9
Tire pressure monitoring systemFunction/notes ............................. 327
Restarting ...................................... 329
Tires
Aspect ratio (definition) .................342
Average weight of the vehicle
occupants (definition) ....................340
Bar (definition) ............................... 340
Characteristics .............................. 340
Checking ........................................ 321
Cleaning ......................................... 322
Definition of terms .........................340
Direction of rotation ......................334
Distribution of the vehicle
occupants (definition) ....................343
DOT, Tire Identification Number
(TIN) ............................................... 339
DOT (Department of
Transportation) (definition) ............340
Flat tire .......................................... 296
GAWR (Gross Axle Weight Rating)
(definition) ..................................... 341
GTW (Gross Trailer Weight)
(definition) ..................................... 341
Guidelines to be observed .............321
GVW (Gross Vehicle Weight)
(definition) ..................................... 341
GVWR (Gross Vehicle Weight
Rating) (definition) .........................341
Increased vehicle weight due to
optional equipment (definition) ......340
Kilopascal (kPa) (definition) ...........341
Labeling (overview) ........................336
Load bearing index (definition) ......342
Load index ..................................... 339
Load index (definition) ...................341
Maximum loaded vehicle weight
(definition) ..................................... 341
Maximum load on a tire
(definition) ..................................... 342
Maximum permissible tire
pressure (definition) ....................... 341
Maximum tire load .........................334
Maximum tire loading (definition) ..341
Optional equipment weight
(definition) ..................................... 342
PSI (pounds per square inch)
(definition) ..................................... 342Replacing ....................................... 336
Service life ..................................... 321
Sidewall (definition) .......................342
Speed index (definition) .................341
Storing ........................................... 322
Structure and characteristics
(definition) ..................................... 340
Temperature .................................. 335
TIN (Tire Identification Number)
(definition) ..................................... 342
Tire bead (definition) ......................342
Tire pressure (definition) ................342
Tire pressures (recommended) ......340
Tire quality classes ........................334
Tire size (data) ............................... 343
Tire size designation, load-bearing
capacity, speed index ....................337
Tire tread ....................................... 321
Tire tread (definition) .....................342
Total load limit (definition) .............343
Traction ......................................... 335
Traction (definition) .......................342
Tread wear ..................................... 335
TWR (permissible trailer drawbar
noseweight) (definition) .................342
Uniform tire quality classification
standards (definition) .....................340
Unladen weight (definition) ............341
Wear indicator (definition) .............342
Wheel rim (definition) ....................341
Tires and wheels (important safety
information) ....................................... 320
Top Tether ............................................ 63
Towing Important safety guidelines ...........313
Towing a trailer
Driving tips .................................... 193
Towing away
Installing the towing eye ................313
Removing the towing eye ...............314
Trailer
Coupling up ................................... 193
Decoupling ..................................... 195
Display message ............................ 221
Power supply ................................. 196
Towing ........................................... 194
Trailer loads and drawbar
noseweights ...................................... 19616IndexBA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 16
Trailer towing .................................... 158
Blind Spot Assist ............................ 193
ESP ®
................................................ 70
PARKTRONIC ................................. 188
Transfer case ..................................... 160
Transmission position display ......... 156
Transmission positions .................... 157
Trip computer (on-board
computer) .......................................... 210
Trip odometer Calling up ....................................... 202
Resetting (on-board computer) ......211
Trunk
Automatic opening ..................... 84, 85
Turn signal (display message) ......... 221
Turn signals ....................................... 119
TWR (permissible trailer drawbar
noseweight) (definition) ................... 342
Type plate see Vehicle identification plate
U
Unlocking Emergency unlocking .......................82
From inside the vehicle (central
unlocking button) ............................. 81
V
Vanity mirror Sun visor ........................................ 262
Vehicle
Data acquisition ............................... 23
Emergency release ..........................82
Equipment ....................................... 19
Exterior view .................................... 26
Individual settings (on-board
computer) ...................................... 205
Loading .......................................... 330
Lowering ........................................ 306
Maintenance .................................... 20
Parking up ..................................... 168
Raising ........................................... 303
Reporting problems .........................22
Towing away .................................. 313
Transporting .................................. 315
Vehicle data
see Technical data
Vehicle identification number
see VIN
Vehicle identification plate .............. 349
Vehicle level (display message) ....... 228
Vehicle tool kit .................................. 294
Video (DVD) ........................................ 204
Video DVD (on-board computer) ...... 204
VIN ...................................................... 349
W
Warning and indicator lamps Overview .......................................... 29
PASSENGER AIRBAG OFF
indicator lamp (only Canada) ...........48
PASSENGER AIRBAG OFF
indicator lamp (only USA) ................42
Warranty ............................................ 348
Wheel bolt tightening torque ........... 306
Wheel chock ...................................... 302
Wheels Changing/replacing .......................336
Changing a wheel .......................... 301
Checking ........................................ 321
Cleaning ......................................... 285
Guidelines to be observed .............321
Mounting a wheel .......................... 304
Removing a wheel ..........................304
Tightening torque ........................... 306
Wheel size/tire size .......................343
Window curtain air bag ....................... 41
Windows see Side windows
Windows (cleaning instructions) ..... 286
Windshield Defrosting ...................................... 142
Infrared reflective .......................... 276
Windshield washer fluid (display
message) ............................................ 234
Windshield washer system Adding washer fluid .......................281
Notes ............................................. 357
Windshield wipers
Important safety notes ..................126
Replacing the wiper blades ....127, 128
Index17BA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 17
increase the risk and potential severity of
hand/arm injury when the driver front air
bag inflates.
R Adjust the front-passenger seat as far back
as possible from the dashboard when the
seat is occupied.
R Occupants, especially children, should
never place their bodies or lean their heads
in the area of the door where the side
impact air bag inflates. This could result in
serious injuries or death should the side
impact air bag be deployed. Always sit as
upright as possible, wear the seat belt
properly and use an appropriately sized
child restraint, infant restraint or booster
seat recommended for the size and weight
of the child.
R Canada only: children under 12 years may
only sit in the front-passenger seat if they
are seated in a child restraint system which
is compatible with BabySmart™ and
approved by Mercedes-Benz. If the child
restraint system is installed properly, the
front-passenger front air bag is deactivated
in conjunction with the BabySmart™
system installed in the vehicle. Otherwise,
the child could be struck by the air bag
when it inflates in a crash. This could lead
to serious or fatal injuries.
Failure to follow these instructions can result
in severe injuries to you or other occupants.
If you sell your vehicle, it is important that you
make the buyer aware of this safety
information. Be sure to give the buyer this
Operator's Manual.GWarning
Accident research shows that the safest place
for children in an automobile is in a rear seat.
A side impact air bag related injury may occur
if occupants, especially children, are not
properly seated or restrained when next to a
side impact air bag which needs to deploy
rapidly in a side impact in order to do its job.
To help avoid the possibility of injury, please
follow these guidelines:(1)Always sit as upright as possible
and use the seat belts properly.
Make sure that children 12 years
old and under use an appropriately
sized child restraint, infant
restraint, or booster seat
recommended for the size and
weight of the child.(2)Always wear seat belts properly.
The air bags are only deployed if the air bag
control unit detects the need for deployment.
Only in the event of such a situation will they
provide their supplemental protection.
The driver and passenger should always wear
their seat belts. Otherwise, it is not possible
for the air bags to provide their supplemental
protection.
In the event of other types of impacts and
impacts below air bag deployment
thresholds, air bags will not deploy. The driver
and passengers will then be protected to the
extent possible by a properly fastened seat
belt. A properly fastened seat belt is also
needed to provide the best possible
protection in a rollover.
Air bags provide additional protection; they
are not, however, a substitute for seat belts.
All vehicle occupants must fasten their seat
belts regardless of whether your vehicle is
equipped with air bags or not.
It is important for your safety and that of your
passenger to have deployed air bags replaced
and to have any malfunctioning air bags
repaired. This will help to make sure the air
bags continue to perform their protective
function for the vehicle occupants in the
event of a crash.
Front air bags
GWarning
Observe "Important safety instructions"
( Y page 38).
Occupant safety39SafetyBA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 39Z
The front air bags increase protection for the
driver's and front passenger's head and
chest.
Driver's air bag : deploys in front of the
steering wheel; front-passenger air bag ;
deploys in front of and above the glove box.
They are deployed:
R in the event of certain frontal impacts
R if the system determines that air bag
deployment can offer additional protection
to that provided by the seat belt
R if the seat belt is fastened
R independently of other air bags in the
vehicle
If the vehicle overturns, the front air bags are
generally not deployed unless the system
detects high vehicle deceleration in a
longitudinal direction.
Your vehicle has adaptive, dual-stage front air
bags. In the event of a collision, the air bag
control unit evaluates the vehicle
deceleration. When the first deployment
threshold is reached, the front air bag is filled
with enough propellant gas to reduce the risk
of injuries. The front air bag is fully deployed
if a second deployment threshold is exceeded
within a few milliseconds.
Vehicles with OCS (USA only): front-
passenger front air bag deployment is also
influenced by the passenger's weight
category as identified by the Occupant
Classification System (OCS) ( Y page 42).
Vehicles with OCS (USA only): the lighter the
passenger side occupant, the higher the
vehicle deceleration rate required for second
stage inflation of the front-passenger front air
bag. In the second stage, the front air bags
are inflated with the maximum amount of
propellant gas available.
The air bags will not deploy in impacts which
do not exceed the system's preset
deployment thresholds. You will then be
protected by the seat belt.
! Vehicles with BabySmart™ (Canada only):
do not place objects heavier than 20 lb
(9 kg) on the front-passenger seat, as this
could be interpreted as the seat being
occupied. In the event of an accident, the
restraint systems on the front-passenger
side are deployed. Have restraint systems
replaced that have been deployed.
The front-passenger front air bag will only
deploy if:
R the system, based on the OCS weight
sensor readings, detects that the front-
passenger seat is occupied (USA only).
R the 42 indicator lamp in the
center console is not lit, USA:
( Y page 42), Canada: ( Y page 48).
R the impact exceeds a preset deployment
threshold
Side impact air bagsGWarning
Observe "Important safety instructions"
( Y page 38).
GWarning!
The pressure sensors for side impact air bag
control are located in the doors. Do not
modify any components of the doors or door
trim panels including, for example, the
addition of door speakers.
Improper repair work on the doors or the
modification or addition of components to the
doors create a risk of rendering the side
impact air bags inoperative or causing
unintended air bag deployment. Work on the
40Occupant safetySafety
BA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 40
Window curtain air bags : are deployed:
R on the side on which an impact occurs
R at the start of an accident with a high rate
of lateral vehicle deceleration or
acceleration, e.g. in a side impact
R regardless of whether the front-passenger
seat is occupied
R independently of seat belt use
R if the vehicle overturns and the system
determines that window curtain air bag
deployment can offer additional protection
to that provided by the seat belt
R independently of the front air bags
The window curtain air bags will not deploy in
impacts which do not exceed the system's
preset thresholds. You will then be protected
by the fastened seat belts.
Occupant classification system (OCS)
How the Occupant Classification
System works
The Occupant Classification System (OCS) is
standard equipment in the USA.
OCS categorizes the occupant on the front-
passenger seat by means of a weight sensor.
The front-passenger front air bag is
automatically deactivated for certain weight
categories. The respective status can be
recognized by the 42 indicator
lamp. When the 42 indicator
lamp is illuminated, the front-passenger front
air bag is deactivated.
The system does not disable:
R the side impact air bag
R the window curtain air bag
R the Emergency Tensioning Devices
To be classified correctly, the front passenger
must sit:
R with the seat belt properly fastened
R in a position that is as upright as possible
with the back against the seat backrest
R with their feet on the floor
If the front-passenger's weight is transferred
to another object in the vehicle (e.g. by
leaning on armrests), the front passenger's
weight category, as determined by OCS, will
not be accurate.
Furthermore, the occupant weight may
appear to increase or decrease due to the
following:
R objects hanging on the seat
R objects lodged under the seat
R objects lodged between the seat and the
center console
R objects lodged between the seat and the
door
R other passengers pushing the seat
R objects applying pressure to the back of
the seat
Make sure that the seat always has clearance
in all directions.
If the front-passenger seat, the seat cover or
the seat cushion are damaged, have the
necessary repair work carried out at an
authorized Mercedes-Benz Center.
For reasons of safety, Mercedes-Benz
recommends that you only use seat
accessories that have been approved by
Mercedes-Benz.
Both the driver and the front passenger
should observe the 42 indicator
lamp to determine whether or not the front
passenger is positioned correctly.42Occupant safetySafety
BA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 42
GWarning
If the 42 indicator lamp
illuminates when an adult or someone larger
than a small individual is in the front-
passenger seat, have the front passenger
reposition himself or herself in the seat until
the 42 indicator lamp goes out,
or check whether objects are caught under or
around the seat.
In the event of a collision, the air bag control
unit will not allow front-passenger front air
bag deployment when the OCS has classified
the front-passenger seat occupant as
weighing as much as or less than a typical 12-
month-old child in a standard child restraint
or if the front-passenger seat is classified as
being empty.
When the OCS senses that the front-
passenger seat occupant is classified as
being up to or less than the weight of a typical
12-month old child in a standard child
restraint, the 42 indicator lamp
will illuminate when the engine is started and
remain illuminated, indicating that the front-
passenger front air bag is deactivated.
When the OCS senses that the front-
passenger seat is classified as being empty,
the 42 indicator lamp will
illuminate when the engine is started and
remain illuminated, indicating that the front-
passenger front air bag is deactivated.
When the OCS senses that the front-
passenger seat occupant is classified as
being heavier than the weight of a typical 12-
month-old child seated in a standard child
restraint or as being a small individual (such
as a young teenager or a small adult), the
42 indicator lamp will illuminate
for approximately 6 seconds when the engine
is started and then, depending on occupant
weight sensor readings from the front-
passenger seat, remain illuminated or go out.
With the 42 indicator lamp
illuminated, the front-passenger front air bag
is deactivated. With the 42
indicator lamp out, the front-passenger front
air bag is activated.
When the OCS senses that the front-
passenger seat occupant is classified as an
adult or someone larger than a small
individual, the 42 indicator lamp
will illuminate for approximately six seconds
when the engine is started and then go out,
indicating that the front-passenger front air
bag is activated.
If the 42 indicator lamp is
illuminated, the front-passenger front air bag
is deactivated and will not be deployed.
If the 42 indicator lamp is not
illuminated, the front-passenger front air bag
is activated and will be deployed:
R in the event of certain frontal impacts
R if impact exceeds a preset deployment
threshold
R independently of the side impact air bags
If the front-passenger front air bag is
deployed, the rate of inflation will be
influenced by:
R the rate of relevant vehicle deceleration as
assessed by the air bag control unit
R the front passenger's weight category as
identified by OCS
For further information, see "Air bag display
messages" ( Y page 215).GWarning
According to accident statistics, children are
safer when properly restrained on the rear
seats than on the front-passenger seat. Thus,
we strongly recommend that children be
placed in the rear seats whenever possible.
Regardless of seating position, children 12
years old and under must be seated and
properly secured in an appropriately sized
child restraint system or booster seat
recommended for the size and weight of the
child.
The infant or child restraint system must be
properly secured with the vehicle's seat belt,
Occupant safety43SafetyBA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 43Z
the seat belt and Top Tether strap, or lower
anchors and Top Tether strap, fully in
accordance with the child seat
manufacturer's instructions.
Occupants, especially children, should always
sit as upright as possible, wear the seat belt
properly and use an appropriate sized infant
restraint, toddler restraint, or booster seat
recommended for the size and weight of the
child.
Children can be killed or seriously injured by
an inflating air bag. Note the following
important information when circumstances
require you to place a child in the front-
passenger seat:
R Your vehicle is equipped with air bag
technology designed to deactivate the
front-passenger front air bag in your vehicle
when the system senses the weight of a
typical 12-month-old child or less along
with the weight of a standard appropriate
child restraint on the front-passenger seat.
R A child in a rear-facing child restraint on the
front-passenger seat will be seriously
injured or even killed if the front-passenger
front air bag inflates in a collision which
could occur under some circumstances,
even with the air bag technology installed
in your vehicle. The only means to eliminate
this risk completely is never to place a child
in a rear-facing child restraint in the front-
passenger seat. We therefore strongly
recommend that you always place a child
in a rear-facing child restraint on the rear
seat.
R If you install a rear-facing child restraint on
the front-passenger seat, make sure the
42 indicator lamp is
illuminated, indicating that the front-
passenger front air bag is deactivated.
Should the 42 indicator lamp
not illuminate or go out while the restraint
is installed, please check installation.
Periodically check the 42
indicator lamp while driving to make sure
the 42 indicator lamp isilluminated. If the 42 indicator
lamp goes out or remains out, do not
transport a child on the front-passenger
seat until the system has been repaired.
A child in a rear-facing child restraint on the
front-passenger seat will be seriously
injured or even killed if the front-passenger
front air bag inflates.
R If you place a child in a forward-facing child
restraint on the front-passenger seat:
- move the seat as far back as possible
- use the proper child restraint
recommended for the age, size and
weight of the child
- secure child restraint with the vehicle's
seat belt according to the child seat
manufacturer's instructions
R For children larger than a typical 12-month-
old child, the front-passenger front air bag
can be activated or deactivated.
Deployment of the driver front air bag does
not mean that the front-passenger front air
bag should also have deployed.
In such cases, the OCS may have determined:
R that the seat was unoccupied or occupied
by the weight up to or less than that of a
typical 12-month-old child seated in a
standard child restraint
R that the seat was occupied by a small
individual (e.g. a young teenager or a small
adult) or a child who weighs more than the
weight of a typical 12-month-old child in a
standard child restraint system
These are examples of when OCS deactivates
the front-passenger front air bag. The air bag
is deactivated despite the impact fulfilling the
criteria for deploying the driver's front air bag.44Occupant safetySafety
BA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 44