
1, 2, 3 ...
115 V socket ...................................... 281
12 V socket see Sockets
360° camera
Function/notes ............................. 193
4ETS
see ETS/4ETS (Electronic
Traction System)
A
ABS (Anti-lock Braking System) Display message ............................ 232
Function/notes ................................ 64
Important safety notes
....................64
Warning lamp ................................. 259
Activating/deactivating cooling
with air dehumidification ................. 131
Active Blind Spot Assist Activating/deactivating (on-
board computer) ............................ 225
Display message ............................ 249
Function/information .................... 202
Trailer towing ................................. 205
Active Driving Assistance package . 202
Active Lane Keeping Assist Activating/deactivating (on-
board computer) ............................ 225
Display message ............................ 248
Function/information .................... 205
Trailer towing ......................... 202, 208
Active light function .........................113
Active Parking Assist Canceling ....................................... 188
Detecting parking spaces .............. 185
Display message ............................ 249
Exiting a parking space .................. 187
Important safety notes .................. 184
Parking .......................................... 186
Towing a trailer .............................. 188
Adaptive Highbeam Assist
Display message ............................ 243
Function/notes ............................. 114
Switching on/off (on-board
computer) ...................................... 227
Additives (engine oil) ........................370Air bags
Display message ............................ 238
Front air bag (driver, front
passenger) ....................................... 44
Important safety notes .................... 42
Knee bag .......................................... 44
PASSENGER AIR BAG OFF
indicator lamp .................................. 47
Pelvis air bag
................................... 46
Safety guidelines ............................. 41
Side impact air bag .......................... 45
Window curtain air bag ....................46
Air-conditioning system
see Climate control
Air filter (display message) ..............246
AIR FLOW ........................................... 132
Air vents Glove box ....................................... 137
Important safety notes .................. 137
Rear ............................................... 138
Setting ........................................... 137
Setting the center air vents ...........137
Setting the side air vents ............... 137
see Climate control
Alarm system
see ATA (Anti-Theft Alarm system)
Anti-lock braking system
see ABS (Anti-lock Braking System)
Anti-theft alarm system
see ATA (Anti-Theft Alarm system)
Approach/departure angle ..............168
Ashtray ............................................... 279
Assistance menu (on-board
computer) .......................................... 224
ASSYST PLUS Displaying a service message ........ 298
Hiding a service message .............. 298
Notes ............................................. 298
Resetting the service interval
display ........................................... 298
Service message ............................ 298
Special service requirements ......... 299
ATA (Anti-Theft Alarm system)
Activating/deactivating ................... 71
Function ........................................... 71
Switching off the alarm .................... 714
Index

Starting the engine with the
SmartKey .......................................
143
Starting with KEYLESS-GO ............. 143
Switching off .................................. 160
Tow-starting (vehicle) ..................... 323
Engine, jump starting
see Jump starting (engine)
Engine electronics
Problem (malfunction) ...................147
Engine oil
Adding ........................................... 301
Additives ........................................ 370
Checking the oil level ..................... 300
Checking the oil level using the
dipstick .......................................... 301
Display message ............................ 245
Filling capacity ............................... 370
Notes about oil grades ................... 369
Notes on oil level/consumption .... 300
Viscosity ........................................ 370
ESP ®
(Electronic Stability
Program) Deactivating/activating ................... 67
Deactivating/activating (AMG
vehicles) .......................................... 68
Display message ............................ 232
ETS/4ETS ........................................ 66
Function/notes ......................... 66, 67
Important safety information ........... 66
Trailer stabilization ........................... 69
Warning lamp ................................. 261
ETS/4ETS (Electronic Traction
System) ................................................ 66
Exhaust check ................................... 162
Exhaust tail pipe (cleaning
instructions) ...................................... 307
Exterior lighting Setting options .............................. 110
see Lights
Exterior mirrors
Adjusting ....................................... 103
Dipping (automatic) .......................105
Folding in/out (automatically) ....... 104
Folding in/out (electrically) ........... 104
Folding in when locking (on-board
computer) ...................................... 230
Out of position (troubleshooting) ...105 Setting ...........................................
104
Storing settings (memory
function) ........................................ 106
Storing the parking position ..........105 F
Filler cap see Fuel filler flap
First-aid kit ......................................... 312
Flat tire MOExtended run-flat system ......... 313
Preparing the vehicle .....................312
see Emergency spare wheel
Floormat ............................................. 295
Fog lamps Switching on/off ........................... 111
Folding the rear bench seat
forwards/back .................................. 272
Fording On flooded roads ........................... 166
Front fog lamps
Display message ............................ 241
Switching on/off ........................... 111
Fuel
Additives ........................................ 367
Consumption statistics ..................219
Displaying the current
consumption .................................. 220
Displaying the range ...................... 220
Driving tips .................................... 162
Fuel gauge ....................................... 31
Grade (gasoline) ............................ 367
Important safety notes .................. 366
Premium-grade unleaded gasoline . 367
Problem (malfunction) ...................157
Quality (diesel) ............................... 368
Refueling ........................................ 154
Tank content/reserve fuel .............366
Fuel filler flap
Opening/closing ............................ 155
Fuel filter (display message) ............246
Fuel level Calling up the range (on-board
computer) ...................................... 22010
Index

Seat belts
Adjusting the driver's and front-
passenger seat belt .........................56
Adjusting the height ......................... 56
Belt force limiters ............................ 58
center rear-compartment seat .........57
Cleaning .........................................
309
Correct usage .................................. 55
Emergency Tensioning Devices ........ 58
Fastening ......................................... 56
Important safety guidelines .............54
Releasing ......................................... 57
Safety guidelines ............................. 41
Switching belt adjustment on/off
(on-board computer) ...................... 229
Warning lamp ................................. 257
Warning lamp (function) ................... 57
see Seat belts
Seats
Adjusting (electrically) .....................98
Adjusting lumbar support ..............100
Adjusting the 4-way lumbar
support .......................................... 101
Adjusting the head restraint ............ 99
Cleaning the cover ......................... 309
Correct driver's seat position ........... 96
Folding the backrest (rear
compartment) forwards/back .......272
Folding the rear bench seat
forwards/back ............................... 272
Important safety notes .................... 97
Seat heating problem .................... 101
Storing settings (memory
function) ........................................ 106
Switching seat heating on/off ....... 101
Sensors (cleaning instructions) .......307
Service menu (on-board computer) . 226
Service products Brake fluid ..................................... 370
Coolant (engine) ............................ 371
DEF special additives .....................369
Engine oil ....................................... 369
Fuel ................................................ 365
Important safety notes .................. 365
Refrigerant (air-conditioning
system) .......................................... 372
Washer fluid ................................... 372Settings
Factory (on-board computer) ......... 230
On-board computer ....................... 226
Setting the air distribution ...............133
Setting the airflow ............................ 134
Side impact air bag ............................. 45
Side marker lamp (display
message) ............................................ 241
Side windows Cleaning ......................................... 306
Convenience closing feature ............ 88
Convenience opening feature .......... 87
Important safety information
...........86
Opening/closing .............................. 87
Problem (malfunction) .....................89
Resetting ......................................... 89
Sliding sunroof
see Panorama roof with power
tilt/sliding panel
SmartKey
Changing the battery ....................... 77
Changing the programming ............. 75
Checking the battery ....................... 77
Convenience closing feature ............ 88
Convenience opening feature .......... 87
Display message ............................ 256
Door central locking/unlocking ....... 74
Important safety notes .................... 74
Loss ................................................. 78
Mechanical key ................................ 76
Positions (ignition lock) ................. 141
Problem (malfunction) .....................78
Starting the engine ........................ 143
Snow chains ...................................... 331
Sockets Center console .............................. 280
General notes ................................ 280
Luggage compartment ................... 281
Rear compartment ......................... 281
Spare wheel
Storage location ............................ 360
Stowing .......................................... 361
Specialist workshop ............................ 27
Special seat belt retractor .................. 61
Speed, controlling see Cruise control 16
Index

Damage to the engine or exhaust system is
caused by the following:
R
using engine oils and oil
filters that have
not been specifically approved for the
service system
R replacing engine oil and oil filters after
the interval for replacement specified by
the service system has been exceeded
R using engine oil additives.
! Do not add too much oil. If the oil level is
above the "max" mark on the dipstick, too
much oil has been added. This can lead to
damage to the engine or the catalytic
converter. Have excess oil siphoned off. Example: engine oil cap
X
Turn cap 0043 counter-clockwise and remove
it.
X Add engine oil.
If the oil level is at or below the MIN mark
on the oil dipstick, add
1.1 US qt (1.0 liter)
of engine oil.
X Replace cap 0043 on the filler neck and turn
clockwise.
Ensure that the cap locks into place
securely.
X Check the oil level again with the oil
dipstick (Y page 301).
Further information on engine oil
(Y page 369). Checking and adding other service
products
Checking coolant level G
WARNING
The engine cooling system is pressurized,
particularly when the engine is warm. When
opening the cap, you could
be scalded by hot
coolant spraying out. There is a risk of injury.
Let the engine cool down before opening the
cap. Wear eye and hand protection when
opening the cap. Open the cap slowly half a
turn to allow pressure to escape.
Only check the coolant level when the vehicle
is on a level surface and the engine has cooled
down.
X Turn the SmartKey to position 2 in the
ignition lock (Y page 141).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice (Y
page 141).
X Check the coolant temperature display in
the instrument cluster.
The coolant temperature must be below
158 ‡ (70 †). X
Slowly turn cap 0043 half a turn counter-
clockwise and allow excess pressure to
escape.
X Turn cap 0043 further
counter-clockwise and
remove it.
If the coolant is at the level of marker bar
0087 in the filler neck when cold, there is
enough coolant in coolant expansion
tank 0044
.302
Engine compartment
Maintenance and care

H
Environmental note
Dispose of service products in an
environmentally responsible manner.
Service products include the following:
R Fuels (e.g. gasoline, diesel)
R Exhaust gas aftertreatment additives, e.g.
DEF
R Lubricants (e.g. engine oil, transmission
oil)
R Coolant
R Brake fluid
R Windshield washer fluid
R Climate control system refrigerant
Comply with all valid regulations with respect
to handling, storing, and disposing of service
fluids.
Components and service products must be
matched. You should therefore only use
products that have been tested and approved
by Mercedes-Benz.
Information about tested and approved
products can be obtained from an authorized
Mercedes-Benz Center or on the Internet at
http://bevo.mercedes-benz.com.
You can recognize service products approved
by Mercedes-Benz by the following
inscription on the containers:
R MB-Freigabe (e.g. MB-Freigabe 229.51)
R MB Approval (e.g. MB Approval 229.51)
Other designations or recommendations
indicate a level of quality or a specification in
accordance with an MB Sheet number (e.g.
MB 229.5). They have not necessarily been
approved by Mercedes-Benz. Fuel
Important safety notes G
WARNING
Fuel is highly flammable. If you handle fuel
incorrectly, there is a risk of fire and
explosion. You must avoid fire, open flames, creating
sparks and smoking. Switch off the engine
and, if applicable, the
auxiliary
heating before
refueling. G
WARNING
Fuel is poisonous and hazardous to health.
There is a risk of injury.
You must make sure that
fuel does not come
into contact with your skin, eyes or clothing
and that it is not swallowed. Do not inhale fuel
vapors. Keep fuel away from children.
If you or others come into contact with fuel,
observe the following:
R Wash away fuel from skin immediately
using soap and water.
R If fuel comes into contact with your eyes,
immediately rinse them thoroughly with
clean water. Seek medical assistance
without delay.
R If fuel is swallowed, seek medical
assistance without delay. Do not induce
vomiting.
R Immediately change out of clothing which
has come into contact with fuel.
Tank capacity Model Total
capacity GLK 250 BlueTEC
15.6 US gal
(59.0 l) All other models
17.4 US gal
(66.0 l) Model Of which
reserve All models
approx.
2.1 US gal (8.0 l)366
Service products and filling capacities
Technical data

Gasoline
Fuel grade
!
Do not use diesel to
refuel vehicles with a
gasoline engine. Do not switch on the
ignition if you accidentally refuel with the
wrong fuel. Otherwise, the fuel will enter
the fuel system. Even small amounts of the
wrong fuel could result in damage to the
fuel system and the engine. The repair
costs are high. Notify a qualified specialist
workshop and have the fuel tank and fuel
lines drained completely.
! You should only refuel with unleaded
premium-grade gasoline as this avoids
damaging the catalytic converter.
If engine running problems are apparent,
have the cause checked immediately and
repaired. Excess unburned fuel can
otherwise enter the catalytic converter,
leading to overheating and possibly
causing a fire.
! To ensure the longevity and full
performance of the engine, only premium-
grade unleaded gasoline may be used.
If there is no premium-grade unleaded
gasoline available and regular unleaded
gasoline must be used, please observe the
following precautions:
R only fill the fuel tank to half full with
regular unleaded gasoline and fill the rest
with premium-grade unleaded gasoline
as soon as possible.
R do not drive at the maximum speed.
R avoid sudden acceleration.
R if the vehicle is carrying a light load, e.g.
two passengers without luggage, do not
allow the engine to rev above 3000 rpm.
R if the vehicle is fully loaded or is being
operated in mountainous terrain, do not
depress the accelerator pedal further
than 00C3 of the pedal travel.
Only refuel using premium-grade unleaded
gasoline with a minimum octane rating of 91. Reformulated Gasoline (RFG) and/or
unleaded
gasoline
with additives
can
be used.
The concentration of additives in the fuel,
however, must not exceed 10%, e.g.:
R Ethanol
R TAME
R ETBE
R IPA
R TBA
For MTBE, the concentration should not
exceed 15%.
The concentration of methanol in gasoline,
including other additives, must not exceed
3%.
Using mixtures of methanol and ethanol is not
permitted. Gasohol, a mixture of 10% ethanol
and 90% unleaded gasoline may be used.
All of these blends must fulfill the fuel
requirements, e.g.:
R knock resistance
R boiling point
R vapor pressure
You will usually find information about the fuel
grade on the pump. If you cannot find the
label on the pump, ask the staff for
assistance.
i For more information, contact a qualified
specialist workshop.
Information on refueling (Y page 154).
Additives
! Operating the engine with fuel additives
can increase wear and tear to the fuel
system high-pressure pump and lead to
contamination of the entire fuel system.
The repair costs are high. This does not
include additives for the removal and
prevention of residue buildup. gasoline
must only be mixed with additives
recommended by Mercedes-Benz. More
information about recommended additives
can be obtained from any authorized
Mercedes-Benz Center. Service products and filling capacities
367
Technical data Z

One of the main problems of poor fuel quality
is the forming of deposits that are created
during the gasoline combustion process.
Mercedes-Benz recommends that you use
branded fuels that have additives.
If you use fuels without these additives over
a longer period of
time,
carbon deposits may
build up. These deposits form at the inlet
valves and in the combustion chamber in
particular.
This could lead to engine problems, e.g.:
R longer engine warm-up phase
R uneven idle
R engine noise
R misfiring
R loss of power
Carbon deposits may form if the availability
of gasoline with relevant additives is
insufficient (in certain regions). In this case,
Mercedes-Benz recommends additives
approved for use in Mercedes-Benz vehicles;
see http://bevo.mercedes-benz.com.
For a list of approved products, consult an
authorized Mercedes-Benz Center. Comply
with the instructions for use on the product
label.
Do not mix other fuel additives with fuel. This
causes unnecessary costs and could damage
the engine.
Diesel Fuel grade
G
WARNING
If you mix diesel fuel with gasoline, the flash
point is lower than that of pure diesel fuel.
When the engine is running, exhaust system
components could overheat without being
noticed. There is a risk of fire.
Never refuel with gasoline. Never
mix gasoline
with diesel fuel.
! Only use commercially available vehicular
ULTRA-LOW SULFUR DIESEL FUEL (ULSD,
15 ppm maximum sulfur content) that meets the ASTM D975 standard. If you do
not
refuel with ULSD, you
may damage the
BlueTEC exhaust gas aftertreatment
system of the vehicle.
! Do not use gasoline to refuel vehicles with
a diesel engine. Do not mix diesel fuel with
gasoline, kerosene or paraffin. This may
otherwise result in damage to the fuel
system and engine.
You will usually find information about the fuel
grade on the pump. If you cannot find the
label on the pump, ask the staff for
assistance.
i For further information, consult a
qualified specialist workshop or on the
Internet at http://www.mbusa.com (USA
only).
Information on refueling (Y page 154).
Bio-diesel - FAME (fatty acid methyl ester)
Mercedes-Benz USA approves the use of bio-
diesel B5 for all BlueTEC diesel engines. The
concentration of bio-diesel in the ULSD may
not exceed 5% by volume.
Pure bio-diesel and diesel fuel with a higher
percentage of bio-diesel, such as B20, can
damage the engine and the fuel system. For
this reason, they are not approved.
For more information, consult the gas station
staff. The bio-diesel B5 label on the gasoline
pump must clearly state that the standard for
ULSD has been fulfilled. If the label is not
clear, do not refuel the vehicle.
Do not refuel your vehicle with fuels unless
they have been approved by Mercedes-Benz.
Information on refueling (Y page 155).
Low outside temperatures
i Diesel fuel with improved cold flow
properties is available during the winter
months. Further information about fuel
properties can be obtained from oil
companies, e.g. at gas stations. 368
Service products and filling capacities
Technical data

DEF
Important safety notes Comply with the important safety notes for
service products when handling DEF
(Y page 365).
DEF is a water-soluble fluid for the exhaust
gas aftertreatment of diesel engines. It is:
R
not poisonous
R colorless and odorless
R not flammable
When you open the DEF container, small
amounts of ammonia vapor may
be released.
Ammonia vapors have a pungent odor and are
particularly irritating to the skin, to mucous
membranes and to the eyes. You may
experience a burning sensation in your eyes,
nose and throat. Coughing and watering of
the eyes are possible.
Do not inhale ammonia vapors. Fill the DEF
tank only in well-ventilated areas.
Low outside temperatures DEF freezes at a temperature of
approximately
12 ‡ (-11
†). The vehicle is
delivered from the factory equipped with a
DEF preheating
system.
Winter operation can
thus be guaranteed even at temperatures
below 12 ‡ (-11 †).
Additives !
Only use DEF in accordance with ISO
22241. Do not use additives with DEF and
do not dilute DEF with water. This may
destroy the BlueTEC exhaust gas
aftertreatment system.
Purity !
Impurities in DEF (e.g. due to other
service products, cleaning agents or dust)
lead to:
R increased emission values
R damage to the catalytic converter R
engine damage
R malfunctions in the BlueTEC exhaust
gas
aftertreatment system
Assuring the purity of DEF is particularly
important with respect to avoiding
malfunctions in the BlueTEC exhaust gas
aftertreatment system.
If DEF is pumped out of the DEF tank, e.g.
during repair work, it must not be returned to
the tank. The purity of the fluid can no longer
be guaranteed.
Filling capacities Model Total capacity
GLK 250 BlueTEC
7.3 US gal
(27.5 l) Engine oil
General notes !
Never use engine oil or an oil filter of a
specification other than is necessary to
fulfill the prescribed service intervals. Do
not change the engine oil or oil filter in
order to achieve longer replacement
intervals than those prescribed. You could
otherwise cause engine damage or
damage
to the exhaust gas aftertreatment.
Follow the instructions in the service
interval display regarding the oil change.
Otherwise, you may damage the engine and
the exhaust gas aftertreatment.
When handling engine oil, observe the
important safety notes on service products
(Y page 365).
The engine oils are matched to the
performance of Mercedes-Benz engines and
service intervals. You should therefore only
use engine oils and oil filters that are
approved for vehicles with maintenance
systems.
For a list of approved engine oils and oil filters,
consult an authorized Mercedes-Benz Service products and filling capacities
369
Technical data Z