brake light MERCEDES-BENZ GL 2012 Owner's Manual

wheelbrace, a robust tow cable and a
folding spade in the vehicle.XWheels and tires: check the tire tread
depth and tire pressure. A table with the
recommended tire pressures can be found
on the B-pillar on the driver's side of your
vehicle.XCheck for damage and remove any foreign
objects, e.g. small stones, from the
wheels/tires.XReplace any missing valve caps.XReplace dented or damaged wheels.XRims: dented or bent rims can result in a
loss of tire pressure and damage the tire
bead. Therefore, check your rims before
driving off-road and replace them as
required.
Checklist after driving off-road
GWARNING
If you notice sudden significant vibrations or
unusual handling performance or if you
suspect that damage has occurred to the
vehicle, you should activate the hazard
warning lamps, gently reduce speed and
carefully head for an area that is located at a
safe distance from the road.
Check the tires and the underside of the
vehicle for damage. If the vehicle seems
unsafe, have the vehicle towed away to the
nearest Mercedes-Benz Center or tire dealer
to be repaired.
Driving over rough terrain places greater
demands on your vehicle than driving on
normal roads. After driving off-road, check
the vehicle. This allows you to detect damage
promptly and reduce the risk of an accident
to yourself and other road users.
XDeactivate the off-road drive program
( Y page 206) or the LOW RANGE off-road
gear ( Y page 206).XDeactivate DSR ( Y page 204).XSet the differential lock setting to AUTO on
the selector wheel ( Y page 208).XLower the vehicle level again to a level
suitable to the road conditions, e.g. to the
highway/high-speed level.XClean the headlamps and rear lights and
check for damage.XClean the front and rear license plates.XClean wheels/tires, wheel mounting and
underbody with a water jet, check them for
foreign objects and damage and rectify this
as required.XAfter the trip, examine without fail the
entire undercarriage, wheels, tires, brakes,
bodywork structure, steering, chassis and
exhaust system for damage.XCheck whether twigs or other parts of
plants have become trapped. These
increase the risk of fire and can damage
fuel pipes, brake hoses or the rubber
bellows of the axle joints and propeller
shafts.XAfter driving for extended periods across
sand, mud, gravel, water or in similarly dirty
conditions, have the brake discs, wheels,
brake pads/linings and axle joints checked
and cleaned.XIf you detect strong vibrations after off-road
travel, check for foreign objects in the
wheels and drive train and remove them if
necessary. Foreign objects can disturb the
balance and cause vibrations.XTest the brakes.
Driving on sand
GWARNING
Do not reduce the tire inflation pressure
before driving through sand. However, if you
do so, remember to correct the tire inflation
pressure before continuing your trip. Driving
with reduced tire inflation pressure increases
the risk of losing control of the vehicle and
rolling over.
176Driving tipsDriving and parking

GWARNING
Never turn the vehicle around on steep inclines. The vehicle might roll over. If the vehicle cannot
complete the attempted climb, back it down in reverse gear.
i Hill start assist will aid you when pulling away on a hill.
For more information, see "Hill start assist" ( Y page 151).
Maximum gradient-climbing capability
For good road surface conditions, the
maximum gradient-climbing capability is
100%, which corresponds to an approach/
departure angle of 45°. Note that the
vehicle's gradient-climbing capability
depends on the off-road conditions.
Accelerate carefully and make sure that the
wheels do not spin when driving on steep
terrain.
i If the load on the front axle is reduced
when pulling away on a steep uphill slope,
the front wheels have a tendency to spin.
4ETS recognizes this and brakes the
wheels accordingly. The rear wheel torque
is increased, making it easier to drive off.
i Vehicles with the Enhanced Off-Road
Package have a differential lock for the
transfer case and a differential lock for the
rear axle to improve vehicle traction.
Brow of hill
When driving up an uphill gradient, slightly
reduce pressure on the accelerator
immediately before reaching the brow of the
hill. Use the vehicle's own impetus to drive
over the top of the hill.
This style of driving prevents:
R the vehicle from lifting off the ground on the
brow of a hill
R loss of traction
R the vehicle from traveling too quickly down
the other side
Driving downhill
R Drive slowly.
R Do not drive at an angle down steep
inclines. Steer into the line of fall and drive
with the front wheels aligned straight.
Otherwise, the vehicle could slip sideways,
tip and rollover.
R Before tackling steep downhill gradients,
select shift range 1.
R Activate DSR. If this is not sufficient, brake
gently. When doing so, make sure that the
vehicle is facing in the direction of the line
of fall.
R Check that the brakes are working normally
after a long downhill stretch.
i The special off-road ABS setting enables
a precise, brief and repeated locking of the
front wheels, causing them to dig into the
loose earth. Be aware that the front wheels
easily skid across the ground surface if
completely braked and therefore lose their
ability to steer.
Driving systems
Cruise control
Important safety 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 or towing a trailer, you must
select shift range 1, 2 or 3 in good time. By
doing so, you will make use of the braking
effect of the engine, which relieves the load
on the brake system and prevents the brakes
from overheating and wearing too quickly.
Driving systems179Driving and parkingZ

time, or adjusts the vehicle's speed to the
last speed stored.
Setting the specified minimum distance
You can set the specified minimum distance
for DISTRONIC by varying the time span
between one and two seconds. This time span
determines the distance that DISTRONIC
should maintain from the vehicle in front,
depending on the road speed. You can see
this distance in the multifunction display
( Y page 187).
GWARNING
It is up to the driver to exercise discretion to
select the appropriate setting given road
conditions, traffic, driver's preferred driving
style and applicable laws and driving
recommendations for safe following distance.
XTo increase: turn thumbwheel ; towards
= .
DISTRONIC then maintains a greater
distance between your vehicle and the
vehicle in front.XTo decrease: turn thumbwheel ;
towards :.
DISTRONIC then maintains a shorter
distance between your vehicle and the
vehicle in front.
i Make sure that you maintain the
minimum distance to the vehicle in front as
required by law. Adjust the distance to the
vehicle in front if necessary.
DISTRONIC displays in the
speedometer
When DISTRONIC is activated, one or
two segments in the set speed range light up.
i For design reasons, the speed displayed
in the speedometer may differ slightly from
the speed set for DISTRONIC.
If DISTRONIC detects a vehicle in front,
segments ; between the speed of the
vehicle in front : and stored speed = light
up.
GWARNING
An intermittent warning sounds and the
distance warning lamp · in the instrument
cluster is illuminated if the Distronic system
calculates that the distance to the vehicle
ahead and your vehicle's current speed
indicate that the Distronic will not be capable
of slowing the vehicle sufficiently to maintain
the preset following distance, which creates
a danger of a collision.
Immediately brake the vehicle to increase
your distance to the preceding vehicle. The
warning sound is intended as a final caution
in which you should intercede with your own
braking inputs to avoid a potentially
dangerous situation. Do not wait for the
operation of the warning signal to intercede
with your own braking. This will result in
potentially dangerous emergency braking
which will not always result in an impact being
avoided.
Tailgating increases the risk of an accident.
186Driving systemsDriving and parking

DISTRONIC may not detect vehicles traveling
on a different line. The distance to the vehicle
in front will be too short.
Other vehicles changing lane
DISTRONIC has not detected the vehicle
cutting in yet. The distance to this vehicle will
be too short.
Narrow vehicles
DISTRONIC has not yet detected the vehicle
in front on the edge of the road, because of
its narrow width. The distance to the vehicle
in front will be too short.
Obstructions and stationary vehicles
DISTRONIC does not brake for obstructions
or stationary vehicles. If, for example, the
detected vehicle turns a corner and reveals
an obstacle or stationary vehicle, DISTRONIC
will not brake for these.
Crossing vehicles
DISTRONIC may detect vehicles that are
crossing your lane by mistake. Activating
DISTRONIC at, for example, a traffic light with
crossing traffic, could cause your vehicle to
pull away at the wrong time.
Level control
Important safety notes
Level control adapts the vehicle level
automatically to the current operating and
driving situation. This results in reduced fuel
consumption and improved handling.
For vehicles with ADS: when you are driving
in ADS COMF or ADS AUTO (Y page 195),
the vehicle is lowered to high-speed level as
Driving systems189Driving and parkingZ

! When parking, pay particular attention to
objects above or below the sensors, such
as flower pots or trailer drawbars.
PARKTRONIC does not detect such objects
when they are in the immediate vicinity of
the vehicle. You could damage the vehicle
or the objects.
The sensors may not detect snow and other
objects that absorb ultrasonic waves.
Ultrasonic sources such as an automatic
car wash, the compressed-air brakes on a
truck or a pneumatic drill could cause
PARKTRONIC to malfunction.
PARKTRONIC may not function correctly on
uneven terrain.
Minimum distanceCenterApproximately 8 in
(approximately 20 cm)CornersApproximately 6 in
(approximately 15 cm)
If there is an obstacle within this range, the
relevant warning displays light up and a
warning tone sounds. If the distance falls
below the minimum, the distance may no
longer be shown.
Warning displays
The warning displays show the distance
between the sensors and the obstacle. The
warning display for the front area is located
on the dashboard above the center air vents.
The warning display for the rear area is in the
roof lamp in the rear compartment.
Warning display for the front area
:Segments on the left-hand side of the
vehicle;Segments on the right-hand side of the
vehicle=Segments showing operational readiness
The warning display for each side of the
vehicle is divided into five yellow and two red
segments. PARKTRONIC is operational if
yellow segments showing operational
readiness = light up.
The selected transmission position
determines which warning display is active
when the engine is running.
Transmission
positionWarning displayDFront area activatedR or NRear and front areas
activatedPNo areas activated
One or more segments light up as the vehicle
approaches an obstacle, depending on the
vehicle's distance from the obstacle.
From the:
R sixth segment onwards, you will hear an
intermittent warning tone for
approximately two seconds.
R seventh segment onwards, you will hear a
warning tone for approximately two
seconds. This indicates that you have now
reached the minimum distance.
Driving systems197Driving and parkingZ

not turn off the engine or shift the automatic
transmission into another gear.
If you do not wait until the shifting procedure
has been entirely completed then it might not
be correctly performed. The transfer case
might be in neutral, thus interrupting the
transfer of power between the engine and the
drive axle.
The vehicle is then freely movable, even if a
gear has been selected, and could
unintentionally be set into motion –
particularly on up – or downhill grades. This
could lead to an accident and cause injury to
yourself and others.
Please observe related messages appearing
in the multifunction display.
From HIGH RANGE to LOW RANGE
! Only carry out the gear change process if:
R the engine is running
R the transmission is in position N
R you are not driving faster than
25 mph (40 km/h)
XPress LOW RANGE button :.
Indicator lamp ; flashes. LOW RANGE
indicator = appears in the multifunction
display.When the gear change is complete,
indicator lamp ; lights up.
While indicator lamp ; is flashing, you can
cancel the gear change by pressing LOW
RANGE button : again.
From LOW RANGE to HIGH RANGE
! Only carry out the gear change process if:
R the engine is running
R the transmission is in position N
R you are not driving faster than 43 mph
(70 km/h)
XPress LOW RANGE button :.
Indicator lamp ; flashes.
If the gear change process has taken place,
indicator lamp ; and LOW RANGE
indicator = in the multifunction display go
out.
While indicator lamp ; is flashing, you can
cancel the gear change by pressing LOW
RANGE button : again.
Messages in the multifunction display
If a gear change process has not been
successful, the following messages may be
displayed in the multifunction display:
Drive max. 25 mph (Canada: 40 km/h): You
have driven faster than 25 mph (40 km/h).
Indicator lamp ; also flashes.
XDrive more slowly to carry out the gear
change process.
Briefly engage gear N : The transmission
is in position D and you are now driving below
25 mph (40 km/h).
XShift the transmission to N to complete the
gear change process.
Shifting process canceled
Reactivate : The shifting process has not
been completed.
XMaintain all gear change conditions and
carry out the gear change process again.
Stop vehicle Apply parking brake : A
warning tone is also heard. The gear change
Off-road driving systems207Driving and parkingZ

lost and steering would no longer be possible.
The differential locks must therefore only be
activated off-road and only if activating the
other driving systems (4ETS, ESP ®
and LOW
Range off-road gear) is no longer sufficient.
Engaging the differential locks
! Pull away slowly when the differential
locks are activated.
Function or performance tests may only be
performed on a 2-axle dynamometer. If you
wish to operate the vehicle on such a
dynamometer, please consult an
authorized Mercedes-Benz Center
beforehand. You could otherwise damage
the drive train or the brake system.
Automatic mode
Use automatic mode ; for all driving
situations, including driving off-road or when
fording.
In automatic mode, the differential locks are
engaged and disengaged according to driving
requirements. This guarantees sufficient
traction for most driving situations with
unrestricted vehicle steerability.
XStart the engine.
The differential locks are in automatic
mode. The indicator lamp in selector
wheel : lights up above symbol for
automatic mode ;.Engaging manuallyGWARNING
Never drive on a paved surface with the center
and rear axle differential locks manually
engaged. Ability to steer the vehicle is greatly
reduced when the differential locks are
manually engaged, increasing the risk of an
accident.
For safety reasons, the locks are
automatically released at a vehicle speed
above 31 mph (50 km/h). Nevertheless, you
should only manually lock the differential if
absolutely necessary because engaged locks
will restrict the vehicle drivetrain while
cornering and cause the vehicle to chatter.
This could cause you to lose control of the
vehicle and cause an accident.
! The differential locks must not be
activated when the vehicle is being towed
or while the wheels are spinning.
Only engage the differential locks manually if
traction in automatic mode is insufficient.
The differential locks can be activated
manually up to a speed of 19 mph
(30 km/h).
XStart the engine.XTurn selector wheel : to desired position
= or ?.
The indicator lamp in selector wheel :
lights up at the corresponding symbol.
The engaged differential appears in the
multifunction display:
AThe differential lock for the transfer case
is locked.
If you have not previously selected the off-
road menu ( Y page 222) in the on-board
Off-road driving systems209Driving and parkingZ

Allow for enough play in the chains to
facilitate turning tight corners.
R a separate brake system for certain types
of trailer.
R a safety switch for braked trailers. Check
the specific legal requirements applicable
to your federal state.
If the trailer detaches from the towing
vehicle, the safety switch applies the
trailer's brakes.
! Do not connect the trailer's brake system
(if featured) to the hydraulic brake system
of the towing vehicle, as the latter is
equipped with an anti-lock brake system.
Doing so will result in a loss of function of
the brake systems of both the vehicle and
the trailer.
i The vehicle's wiring harness features a
line to the brake indicator lamp.XMake sure that the automatic transmission
is set to position P.XApply the vehicle's parking brake.XStart the engine.XSelect highway level.XVehicles with the adaptive damping
system: set ADS to AUTO or COMF .XSwitch off the engine.XClose all doors and the tailgate.XCouple up the trailer.XEstablish all electrical connections.
i
Vehicles with the AIRMATIC package:
with a trailer attached, the vehicle will
always remain at highway level. When
coupling up a trailer, please observe the
following:
R if highway level has not been set
manually, the vehicle will automatically
sink to highway level as soon as it
reaches a speed of 5 mph (8 km/h).
R high-speed level is not available.
These restrictions apply to all accessories
powered through a connection to the trailer
power socket of your vehicle, e.g. a bicycle
carrier.
Towing a trailer
There are numerous legal requirements
concerning the towing of a trailer, e.g. speed
restrictions. Make sure that your vehicle/
trailer combination complies with the local
requirements not only in your area of
residence but also at any location to which
you are traveling. The police and local
authorities can provide reliable information.
Please observe the following when towing a
trailer:
R To acquaint yourself with driving with a
trailer and with the resulting changes to
handling, you should practice cornering,
stopping and reversing in a traffic-free
location.
R Before driving, check:
- the trailer tow hitch
- the safety switch for braked trailers
- the safety chains
- the electrical connections
- the lights
- the wheels
R Adjust the exterior mirrors to provide an
unobstructed view of the rear section of the
trailer.
R If the trailer features electronically
controlled brakes, pull away the vehicle/
trailer combination carefully, manually
brake using the brake controller, and check
the brakes for correct function.
R Secure any objects on the trailer to prevent
the cargo from slipping when the vehicle is
in motion.
R If you couple up a trailer, regularly check
the cargo for secure fastening and make
sure that the trailer lamps and (if
applicable) the trailer brakes are
functioning correctly.
R Bear in mind that the handling will be less
stable when towing a trailer than when
Trailer towing211Driving and parkingZ

Safety systemsDisplay messagesPossible causes/consequences and M Solutions!÷
Unavailable See
Operator's ManualGRisk of accident
ABS (Anti-lock Braking System), ESP ®
(Electronic Stability
Program), BAS (Brake Assist), PRE-SAFE ®
, hill start assist and
ESP ®
trailer stabilization are temporarily not available.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster.
The self-diagnosis function might not be complete, for example.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XCarefully drive a suitable distance making slight steering
movements at a speed above 12 mph (20 km/h).
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
XDrive on carefully.XVisit a qualified specialist workshop.GRisk of accident
ABS, ESP ®
, BAS, PRE-SAFE ®
, hill start assist and ESP ®
trailer
stabilization are temporarily not available.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster.
For example, the on-board voltage may be insufficient.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XDrive on carefully.
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
XDrive on carefully.XVisit a qualified specialist workshop.Display messages233On-board computer and displaysZ

Display messagesPossible causes/consequences and M Solutions!÷
Inoperative See
Operator's ManualGRisk of accident
ABS, ESP ®
, BAS, PRE-SAFE ®
, hill start assist and ESP ®
trailer
stabilization are not available due to a malfunction.
The $ (USA only)/ J (Canada only), ÷, å and !
warning lamps in the instrument cluster also light up.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XDrive on carefully.XVisit a qualified specialist workshop immediately.÷
Unavailable See
Operator's ManualGRisk of accident
ESP ®
, PRE-SAFE ®
and BAS, hill start assist and ESP ®
trailer
stabilization are temporarily not available.
In addition, the ÷ and å warning lamps light up in the
instrument cluster.
The self-diagnosis function might not be complete, for example.
The brake system continues to function normally, but without the
functions listed above.
XCarefully drive on a suitable stretch of road, making slight
steering movements, at a speed above 20 km/h.
If the display message disappears, ESP ®
is available again.
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
XDrive on carefully.XVisit a qualified specialist workshop.ESP ®
, PRE-SAFE ®
and BAS, hill start assist and ESP ®
trailer
stabilization are temporarily not available.
In addition, the ÷ and å warning lamps light up in the
instrument cluster.
For example, the on-board voltage may be insufficient.
The brake system continues to function normally, but without the
functions listed above.XDrive on carefully.XVisit a qualified specialist workshop immediately.234Display messagesOn-board computer and displays