tow MERCEDES-BENZ R-Class 2012 W251 User Guide

Change of address or ownership
In the event of a change of address, please
send us the "Change of Address Notice"
found in the Service and Warranty
Information Booklet, or simply call the
Mercedes-Benz Customer Assistance Center
(in the USA) at the hotline number
1-800-FOR-MERCedes(1-800-367-6372) or
Customer Service Center (in Canada) at
1-800-387-0100. This will assist us in
contacting you in a timely manner should the
need arise.
If you sell your Mercedes, please leave the
entire literature in the vehicle so that it is
available to the next owner.
If you bought this vehicle used, be sure to
send in the "Notice of Purchase of Used
Truck" found in the Service and Warranty
Information Booklet, or call the Mercedes-
Benz Customer Assistance Center (in the
USA) at
1-800-FOR-MERCedes(1-800-367-6372) or
Customer Service (in Canada) at
1-800-387-0100.
Vehicle operation outside the USA
and Canada
If you plan to operate your vehicle in foreign
countries, please be aware that:
R service facilities or replacement parts may
not be readily available.
R unleaded fuel for vehicles with a catalytic
converter may not be available. Leaded fuel
may cause damage to the catalytic
converter.
R the fuel may have a considerably lower
octane rating. Unsuitable fuel can cause
engine damage.
Operating safety
Safety notes
GWARNING
Work improperly carried out on electronic
components and associated software could
cause them to cease functioning. Because the
vehicle's electronic components are
interconnected, any modifications made may
produce an undesired effect on other
systems. Electronic malfunctions could
seriously impair the operating safety of your
vehicle.
Contact an authorized Mercedes-Benz Center
for repairs or modifications to electronic
components.
Other improper work or modifications on the
vehicle could also have a negative impact on
the operating safety of the vehicle.
Some safety systems only function when the
engine is running. You should therefore never
turn off the engine while driving.
GWARNING
Heavy blows against the vehicle underbody or
tires/wheels may cause serious damage and
impair the operating safety of your vehicle.
Such blows can be caused, for example, by
running over an obstacle, road debris or a
pothole.
If you feel a sudden significant vibration or
ride disturbance, or you suspect that damage
to your vehicle has occurred:
R turn on your hazard warning flashers.
R slow down carefully.
R drive with caution to an area which is a safe
distance from the road.
Inspect the vehicle underbody and tires/
wheels for possible damage. If the vehicle
appears unsafe, have it towed to the nearest
authorized Mercedes-Benz Center or other
qualified maintenance or repair facility for
further inspection or repairs.
Introduction23Z

Center console, lower sectionFunctionPageHStowage compartment248IStowage tray248JStowage compartment248KCup holder263FunctionPageLStowage compartment248Ashtray265Cigarette lighter266Center console33At a glance

For more information about releasing the seat
belt with release button ?, see "Releasing
seat belts" ( Y page 54).
Seat belt adjustment
The seat-belt adjustment function adjusts the
driver's and front-passenger seat belt to the
upper body of the occupants.
The belt strap is tightened slightly when:
R you engage the belt tongue in the belt
buckle and you then turn the SmartKey to
position 2 in the ignition lock.
R the SmartKey is in position 2 in the ignition
lock and you then engage the belt tongue
in the buckle.
The seat-belt adjustment will apply a
retraction force if any slack is detected
between the occupant and the seat belt. Do
not hold on to the seat belt tightly while it is
adjusting. You can switch the seat-belt
adjustment on and off in the on-board
computer ( Y page 209).
The seat-belt adjustment is an integral part of
the PRE-SAFE ®
convenience function. More
information about PRE-SAFE ®
can be found
in the "PRE-SAFE ®
(preventative occupant
protection)" section ( Y page 49).
Belt height adjustment
You can adjust the seat belt height on the
driver's seat and the front-passenger seat.
Adjust the height so that the upper part of the
seat belt is routed across the center of your
shoulder.
XTo raise: slide the belt sash guide upwards.
The belt sash guide engages in various
positions.XTo lower: press and hold belt sash guide
release :.XSlide the belt sash guide downwards.XRelease belt sash guide release : and
make sure that the belt sash guide has
engaged.
Releasing seat belts
XPress release button ?(Y page 53) and
guide belt tongue ; back towards belt
sash guide :.
!
Make sure that the seat belt is fully rolled
up. Otherwise, the seat belt or belt tongue
will be trapped in the door or in the seat
mechanism. This could damage the door,
the door trim panel and the seat belt.
Damaged seat belts can no longer fulfill
their protective function and must be
replaced. Consult an authorized Mercedes-
Benz Center.
Belt warning for the driver and front
passenger
Regardless of whether the driver and front
passenger have fastened their seat belts
already, the 7 seat belt warning lamp
lights up for 6 seconds after every engine
start. It then goes out if the driver and the
front passenger have fastened their seat
belts.
If the driver's seat belt is not fastened after
the engine is started, an additional warning
tone will sound. The warning tone goes out
after approximately six seconds or once the
driver's seat belt is fastened.
54Occupant safetySafety

If the driver or front passenger have not
fastened their seat belt after 6 seconds and
the doors are closed, the 7 seat belt
warning lamp lights up.
R until the driver or the front passenger have
fastened their seat belts
R if a vehicle speed of 15 mph(25 km/h) is
exceeded once, a warning tone with
increasing intensity sounds additionally for
a maximum of 60 seconds or until the driver
or front passenger have fastened their seat
belts.
If the driver or front passenger undo their seat
belts during the journey, the 7 seat belt
warning lamp lights up and the warning tone
sounds again.
The warning tone ceases even if the driver or
front passenger have still not fastened their
seat belt after 60 seconds. The 7 seat belt
warning lamp stops flashing but continues to
be lit.
Once the vehicle is stationary, the warning
tone is reactivated and the 7 seat belt
warning lamp starts to flash again if the
vehicle speed exceeds 15 mph(25 km/h)
once.
The 7 seat belt warning lamp only goes
out if:
R both the driver and the front passenger
have fastened their seat belts.
or
R the vehicle is stationary and a door is open.
i For more information on the 7 seat
belt warning lamp, see "Warning and
indicator lamps in the instrument cluster,
seat belt" ( Y page 238).Emergency Tensioning Devices, seat
belt force limiters
The seat belts for the following seats are
equipped with ETDs and seat belt force
limiters:
R driver's and front-passenger seat
R the outer seats in the second row
R the seats in the third row
The ETDs tighten the seat belts in an accident,
pulling them close against the body.
The ETDs do not correct incorrect seat
positions or incorrectly fastened seat belts.
The ETDs do not pull vehicle occupants back
towards the backrest.
Seat belt force limiters, when triggered, help
to reduce the peak force exerted by the seat
belt on the vehicle occupant.
The seat belt force limiters for the front seats
are synchronized with the front air bags.
These take on a part of the deceleration force.
Thus, the force exerted on the occupant is
distributed over a greater area.
The ETDs can only be activated when:
R the ignition is switched on.
R the restraint systems are operational; see
"SRS warning lamp" ( Y page 38)
R the belt tongue is engaged in the buckle on
each of the lap-shoulder belts in the front.
R the front-passenger seat is occupied and
the belt tongue is engaged in the buckle on
the front-passenger side.
The ETDs on the outside seats in the second
row and on the seats in the third row are
triggered independently of the lock status of
the seat belts.
The ETDs are triggered depending on the type
and severity of an accident:
R if, in the event of a head-on or rear-end
collision, the vehicle decelerates or
accelerates rapidly in a longitudinal
Occupant safety55SafetyZ

vehicle are turning at a speed of more than
9 mph (15 km/h).
You could therefore be locked out when:
R the vehicle is being pushed.
R the vehicle is being towed.
R the vehicle is being tested on a
dynamometer.
You can switch the automatic locking
function on and off using the on-board
computer ( Y page 208).
Unlocking the driver's door
(mechanical key)
If the vehicle can no longer be unlocked with
the SmartKey, use the mechanical key.
If you use the mechanical key to unlock and
open the driver's door, the anti-theft alarm
system will be triggered ( Y page 69).
XTake the mechanical key out of the
SmartKey ( Y page 75).XInsert the mechanical key into the lock of
the driver's door as far as it will go.XTurn the mechanical key counter-clockwise
as far as it will go to position 1 and hold
it in this position.XPull the door handle beyond the first
resistance.
The locking knob pops up.
The door is unlocked.XTurn the mechanical key back and remove
it.XPull the door handle again.XInsert the mechanical key into the
SmartKey.
Locking the vehicle
If the vehicle can no longer be locked with the
SmartKey, you can lock it by taking the
following steps.
XClose the front-passenger door, the rear
door on the front-passenger side and the
tailgate.XOpen the driver’s door and the rear door on
the driver’s side.XPress the locking button on the driver’s
door ( Y page 80).
The locking knobs in the front-passenger
door and in the rear doors drop down.XPress down the locking knobs in the front-
passenger and rear doors manually, if
necessary.XClose the driver's door from the outside.XPress down the locking knob of the driver's
door by reaching in through the open rear
door.
i Make sure that you have the SmartKey on
your person and that it has not been left in
the vehicle.
XClose the rear door on the driver’s side.XMake sure that the doors and the tailgate
are locked.
i If you lock the vehicle as described above,
the fuel filler flap is not locked. The anti-
theft alarm system is not armed.
Cargo compartment
Important safety notes
Do not leave the SmartKey in the cargo
compartment. You could otherwise lock
yourself out.
Cargo compartment81Opening/closingZ

Adjusting seat fore-and-aft adjustment
(outer seats in the 2nd row of seats)XPull lever : in the direction of the arrow to
the pressure point and hold it in this
position.XSlide the seat forwards or backwards to the
desired position.XRelease lever :.
The seat engages audibly.
Adjusting the backrest angle
Outer seats, 2nd row
3rd row of seats
XPull lever : in the direction of the arrow to
the pressure point and hold it in this
position.XPress your back lightly against the backrest
to tilt it towards the rear.
or
XRelieve the pressure on the backrest to
allow it to fold forwards.XRelease lever : once the backrest is in the
desired position.XLean back firmly against the backrest to
ensure that it is engaged.
Adjusting the armrest (2nd row of
seats)
6-seat vehicles
You can fold the armrests in the 2nd row of
seats up, e.g. when loading the vehicle, and
adjust their height.
XTo fold up: fold the armrest up until it
engages in the vertical position.XTo adjust the height: gently push the
engaged armrest backwards to release it.XFirst fold the armrest all the way down to
its lowest position and then back up to the
desired position until it engages.
i If you want to lower the armrest, you must
first fold it up. Then adjust the height as
described above.
7-seat vehicles
The backrest of the center seat in the 2nd row
can be used as an armrest.
GWARNING
The folded second-row middle seat is
intended to serve as an armrest only. Do not
fold the second-row middle seat and allow
occupants to use the folded second-row
middle seat as a footrest while driving. All
vehicle occupants must keep both feet on the
floor in front of their seat. Otherwise,
occupants could slide under the seat belt in a
collision. If occupants slide under it, the belt
102SeatsSeats, steering wheel and mirrors

Useful information ............................144
Breaking-in notes .............................. 144
Driving ............................................... 144
Automatic transmission ...................150
Refueling ............................................ 156
Parking ............................................... 163
Driving tips ........................................ 165
Driving systems ................................ 170
Trailer towing .................................... 191143Driving and parking

Engaging park position PXPush the DIRECT SELECT lever in the
direction of arrow P.
i
The automatic transmission shifts
automatically into park position P if you
open the driver's door when the vehicle is
stationary or driving at very low speed, and
the transmission is in position D or R.
! If the engine speed is too high or the
vehicle is moving, do not shift the
automatic transmission directly from D to
R , from R to D or directly to P. The
automatic transmission could otherwise be
damaged.
Engaging reverse gear R
! Only shift the automatic transmission to
R when the vehicle is stationary.
XWhen the vehicle is stationary, depress the
brake pedal.XPush the DIRECT SELECT lever up past the
first point of resistance.
Shifting to neutral N
XWhen the vehicle is stationary, depress the
brake pedal.XPush the DIRECT SELECT lever up or down
to the first point of resistance.
If the engine has been switched off, the
automatic transmission automatically
switches to N.
Remaining in neutral N
If the automatic transmission is to remain in
neutral N, e.g. for washing the vehicle in car
washes with a towing device, please observe
the following instructions:
GWARNING
When leaving the SmartKey in the starter
switch, do not leave children unattended in
the vehicle. It is possible for children to switch
on the ignition which could result in
unsupervised use of vehicle equipment.
Unsupervised use of vehicle equipment could
result in an accident and/or serious personal
injury.
Using the SmartKey:
R make sure that the ignition is switched on.
R when the vehicle is stationary, depress the
brake pedal and keep it depressed.
R shift to neutral N.
R release the brake pedal.
R if applied, release the parking brake.
R switch off the ignition and leave the
SmartKey in the ignition lock.
Using KEYLESS-GO:
R make sure that the ignition is switched on.
R when the vehicle is stationary, depress the
brake pedal and keep it depressed.
R engage park position P.
R release the brake pedal.
R remove the Start/Stop button from the
ignition lock.
R insert the SmartKey into the ignition lock.
R switch on the ignition.
R depress the brake pedal and keep it
depressed.
R shift to neutral N.
R release the brake pedal.
R if applied, release the parking brake.
R switch off the ignition and leave the
SmartKey in the ignition lock.
Shifting to transmission position DXWhen the vehicle is stationary, depress the
brake pedal.XPush the DIRECT SELECT lever down past
the first point of resistance.
Transmission position display
The current transmission position is shown in
the multifunction display.
Automatic transmission151Driving and parkingZ

:Transmission position
iThe arrows in the transmission position
display show how and into which
transmission positions you can change
using the DIRECT SELECT lever.
Transmission positions
BPark position
Do not shift the transmission into
position P(Y page 163) unless the
vehicle is stationary. The parking
lock should not be used as a brake
when parking. In addition to
engaging the parking lock, you
must always apply the parking
brake to secure the vehicle.
If the vehicle electronics are
malfunctioning, the transmission
may be locked in position P.
Have the vehicle electronics
checked at a qualified specialist
workshop, e.g. an authorized
Mercedes-Benz Center,
immediately.CReverse gear
Only shift the transmission to R
when the vehicle is stationary.ANeutral
Do not shift the transmission to N
while driving. The transmission
could otherwise be damaged.
No power is transmitted from the
engine to the drive wheels.
Releasing the brakes will allow you
to move the vehicle freely, e.g. to
push it or tow it.
If ESP ®
is deactivated or faulty:
only shift the transmission to
position N if the vehicle is in danger
of skidding, e.g. on icy roads.
! Rolling in neutral N can damage
the drive train.7Drive
The automatic transmission
changes gear automatically. All
forward gears are available.
Changing gear
The automatic transmission shifts to the
individual gears automatically when it is in
transmission position D. This automatic
gearshifting behavior is determined by:
R a shift range restriction, if selected
R the selected drive program
E/S (Y page 153)
R the position of the accelerator pedal
R the road speed
152Automatic transmissionDriving and parking

Driving tips
Kickdown
Use kickdown for maximum acceleration.
XVehicles for USA: fully depress the
accelerator pedal.
The transmission shifts to a lower gear
depending on the engine speed.XVehicles for Canada: depress the
accelerator pedal beyond the pressure
point.
The transmission shifts to a lower gear
depending on the engine speed.
Rocking the vehicle free
Rocking the vehicle free by shifting back and
forth between transmission positions D and
R can help to free a vehicle that has become
stuck in mud or snow. The engine
management system of the vehicle limits
shifting back and forth between transmission
positions D and R to a maximum speed of
5 mph (9 km/h). To shift back and forth
between transmission positions D and R,
move the selector lever up and down beyond
the pressure point.
Working on the vehicle
GWARNING
When working on the vehicle, engage the
parking brake and shift the automatic
transmission into park position P. Otherwise
the vehicle could roll away which could result
in an accident and/or serious personal injury.
Trailer towing
XWhen towing a trailer and driving downhill,
shift to the lower gear if the automatic
transmission constantly shifts between
two gears.XEngaging a lower gear and reducing the
speed reduces the risk of the engine
overheating.Program selector button
General information
The program selector button allows you to
choose between different driving
characteristics.
Program selector button
E EconomyComfortable, economical
drivingS SportSporty driving style
i
For further information on the automatic
drive program, see ( Y page 154).
XPress program selector button :
repeatedly until the letter for the desired
gearshift program appears in the
multifunction display.
Steering wheel paddle shifters
:Left-hand steering wheel paddle shifter;Right-hand steering wheel paddle shifterAutomatic transmission153Driving and parkingZ