2016 MERCEDES-BENZ GL-Class check engine light

Useful information
i
This Operator's Manual describes all
models and all standard and optional equip-
ment of your vehicle available at the time of
publication of the Operator's Manual.
Country-specific differences are possible.
Please note that your vehicle may not be
equipped with all features described. This
also applies to safety-related systems and
functions.
iRead the information on qualified special-
ist workshops (
Ypage 29).
Correct driver's seat position
GWARNING
You could lose control of your vehicle if you do the following while driving:
Radjust the driver's seat, head restraint,
steering wheel or mirrors
Rfasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint, steer-
ing wheel and mirror and fasten your seat belt before starting the engine.
XObserve the safety guidelines on seat
adjustment (
Ypage 109).
XCheck whether you have adjusted seat =
properly (
Ypage 110).
Electrical seat adjustment (
Ypage 110)
When adjusting the seat, make sure that:
Ryou are as far away from the driver's air bag
as possible
Ryou are sitting in a normal upright position
Ryou can fasten the seat belt properly
Ryou have moved the backrest to an almost
vertical position
Ryou have set the seat cushion angle so that
your thighs are gently supported
Ryou can depress the pedals properly
XCheck whether the head restraint is adjus-
ted properly (
Ypage 110).
When doing so, make sure that you have
adjusted the head restraint so that the back
of your head is supported at eye level by the
center of the head restraint.
XObserve the safety notes on steering col-
umn adjustment (
Ypage 121).
XMake sure that steering wheel :is adjus-
ted properly.
Adjusting the steering wheel manually
(
Ypage 121)
Adjusting the steering wheel electrically
(
Ypage 122)
When adjusting the steering wheel column,
make sure that:
Ryou can hold the steering wheel with your
arms slightly bent
Ryou can move your legs freely
Ryou can see all the displays in the instru-
ment cluster clearly
XObserve the safety guidelines for seat belts
(
Ypage 46).
XCheck whether you have fastened seat
belt ;properly (
Ypage 48).
108Correct driver's seat position
Seats, steering wheel and mirrors

Problems with the seat ventilation
ProblemPossible causes/consequences andMSolutions
The seat ventilation has
switched off prema-
turely or cannot be
switched on.The on-board voltage is too low because too many electrical con-
sumers are switched on.
XSwitch off electrical consumers that you do not need, such as
the rear window defroster or interior lighting.
Once the battery is sufficiently charged, the seat ventilation will
switch back on automatically.
Steering wheel
Important safety notes
GWARNING
You could lose control of your vehicle if you do the following while driving:
Radjust the driver's seat, head restraint,
steering wheel or mirrors
Rfasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint, steer-
ing wheel and mirror and fasten your seat belt before starting the engine.
GWARNING
Children could injure themselves if they
adjust the steering wheel. There is a risk of
injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle.
The electrically adjustable steering wheel can
still be adjusted when there is no SmartKey in
the ignition lock.
Adjusting the steering wheel man-
ually
GWARNING
If the steering wheel is unlocked while the
vehicle is in motion, it could change position
unexpectedly. This could cause you to lose
control of the vehicle. There is a risk of an
accident.
Before starting off, make sure the steering
wheel is locked. Never unlock the steering
wheel while the vehicle is in motion.
:Release lever
;To adjust the steering wheel height
=To adjust the steering wheel position
(fore-and-aft adjustment)
XPush release lever :down completely.
The steering column is unlocked.
XAdjust the steering wheel to the desired
position.
XPush release lever :up completely.
The steering column is locked.
XCheck if the steering column is locked.
When doing so, try to push the steering
wheel up or down or try to move it in the
fore-and-aft direction.
Steering wheel121
Seats, steering wheel and mirrors
Z

Problems with the windshield wipers
ProblemPossible causes/consequences andMSolutions
The windshield wipers
are jammed.Leaves or snow, for example, may be obstructing the windshield
wiper movement. The wiper motor has been deactivated.
XFor safety reasons, you should remove the SmartKey from the
ignition lock.
or
XSwitch off the engine using the Start/Stop button and open the driver's door.
XRemove the cause of the obstruction.
XSwitch the windshield wipers back on.
The windshield wipers
fail completely.The windshield wiper drive is malfunctioning.
XSelect another wiper speed on the combination switch.
XHave the windshield wipers checked at a qualified specialist
workshop.
142Windshield wipers
Lights and windshield wipers

It is only possible to switch between KEY-
LESS-GO mode and SmartKey operation
when the transmission is in positionP.
XRemove Start/Stop button:from ignition
lock ;.
You do not have to remove the Start/Stop
button from the ignition lock when you leave
the vehicle. You should, however, always take
the SmartKey with you when leaving the vehi-
cle. As long as the SmartKey is in the vehicle:
Rthe vehicle can be started using the Start/
Stop button
Rthe electrically powered equipment can be
operated
Starting the engine
Important safety notes
GWARNING
If children are left unsupervised in the vehicle,
they could:
Ropen the doors, thus endangering other
people or road users.
Rget out and disrupt traffic.
Roperate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
Rrelease the parking brake.
Rshifting the automatic transmission out of
park position P
RStart the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
GWARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There
is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces with-
out sufficient ventilation.
GWARNING
Flammable materials introduced through
environmental influence or by animals can
ignite if in contact with the exhaust system or
parts of the engine that heat up. There is a risk
of fire.
Carry out regular checks to make sure that
there are no flammable foreign materials in
the engine compartment or in the exhaust
system.
!Do not depress the accelerator when
starting the engine.
General notes
Vehicles with a gasoline engine: the cata-
lytic converter is preheated for up 30 seconds
after a cold start. The sound of the engine may
change during this time.
Automatic transmission
XShift the transmission to position P
(
Ypage 174).
The transmission position display in the
multifunction display shows
P (
Ypage 174).
iYou can start the engine in transmission
position Pand N.
Starting procedure with the SmartKey
XTo start a diesel engine : turn the Smart-
Key to position 2in the ignition lock
(
Ypage 165).
The % preglow indicator lamp in the
instrument cluster lights up.
XTurn the SmartKey to position 3in the igni-
tion lock and release it as soon as the
engine is running (
Ypage 165).
iVehicles with a diesel engine: you can
start the engine without preglow if the
engine is warm.
Driving167
Driving and parking
Z

ProblemPossible causes/consequences andMSolutions
Vehicles with a gaso-
line engine:
The engine is not run-
ning smoothly and is
misfiring.There is a malfunction in the engine electronics or in a mechanical
component of the engine management system.
XOnly depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic con-
verter and damage it.
XHave the cause rectified immediately at a qualified specialist
workshop.
The coolant tempera-
ture gage shows a value
above 248 ‡ (120 †).The coolant level is too low. The coolant is too hot and the engine
is no longer being cooled sufficiently.
XStop as soon as possible and allow the engine and the coolant to
cool down.
XCheck the coolant level (Ypage 373). Observe the warning
notes as you do so and add coolant if necessary.
Automatic transmission
Important safety notes
GWARNING
If the engine speed is above the idling speed
and you engage transmission position Dor R,
the vehicle could pull away suddenly. There is
a risk of an accident.
When engaging transmission position Dor R,
always firmly depress the brake pedal and do not simultaneously accelerate.
GWARNING
The automatic transmission switches to neu-
tral position Nwhen you switch off the engine.
The vehicle may roll away. There is a risk of an
accident.
After switching off the engine, always switch
to parking position P. Prevent the parked vehi-
cle from rolling away by applying the parking
brake.
DIRECT SELECT lever
Overview of transmission positions
jPark position with parking lock
kReverse gear
iNeutral
hDrive
The DIRECT SELECT lever is on the right of the
steering column.
The DIRECT SELECT lever always returns to
its original position. The current transmission
position P,R, Nor Dappears in the transmis-
sion position display in the multifunction dis-
play (
Ypage 174).
Automatic transmission173
Driving and parking
Z

Opening the fuel filler flap
:To open the fuel filler flap
;To insert the fuel filler cap
=Instruction label for fuel type to be refu-
eled
?Tire pressure table
XSwitch off the engine.
XRemove the SmartKey from the ignition
lock.
or, on vehicles with KEYLESS‑ GO:
XOpen the driver's door.
The on-board electronics now have status
0. This is the same as the SmartKey having
been removed.
The driver’s door can be closed again.
XPress the fuel filler flap in the direction of
arrow:.
The fuel filler flap swings up.
XTurn the fuel filler cap counterclockwise
and remove it.
XInsert the fuel filler cap into the holder
bracket on the inside of filler flap ;.
XCompletely insert the filler neck of the fuel
pump nozzle into the tank, hook in place
and refuel.
XOnly fill the tank until the pump nozzle
switches off.
Do not add any more fuel after the pump
stops filling for the first time. Otherwise, fuel
may leak out.
Vehicles with a diesel engine: the filler neck is
designed for refueling at diesel filling pumps.
Closing the fuel filler flap
XReplace the cap on the filler neck and turn clockwise until it engages audibly.
XClose the fuel filler flap.
Close the fuel filler flap before locking the
vehicle.
If you are driving with the fuel filler cap open,
the 8 reserve fuel warning lamp flashes. A
message appears in the multifunction display
(
Ypage 309).
In addition, the ;Check Engine warning
lamp may light up (
Ypage 334).
184Refueling
Driving and parking

Heavy and light loads
GWARNING
If you rest your foot on the brake pedal while
driving, the braking system can overheat. This increases the stopping distance and can even
cause the braking system to fail. There is a
risk of an accident.
Never use the brake pedal as a footrest. Never
depress the brake pedal and the accelerator
pedal at the same time.
!Depressing the brake pedal constantly
results in excessive and premature wear to
the brake pads.
If the brakes have been subjected to a heavy
load, do not stop the vehicle immediately.
Drive on for a short while. This allows the air-
flow to cool the brakes more quickly.
Wet roads
If you have driven for a long time in heavy rain
without braking, there may be a delayed reac-
tion from the brakes when braking for the first
time. This may also occur after the vehicle has
been washed or driven through deep water.
You then have to depress the brake pedal
more firmly. Maintain a greater distance from
the vehicle in front.
After driving on a wet road or having the vehi-
cle washed, brake firmly while paying atten-
tion to the traffic conditions. This will warm up
the brake discs, thereby drying them more
quickly and protecting them against corro-
sion.
Limited braking performance on salt-
treated roads
If you drive on salted roads, a layer of salt
residue may form on the brake discs and
brake pads. This can result in a significantly
longer braking distance.
RBrake occasionally to remove any possible
salt residue. Make sure that you do not
endanger other road users when doing so.
RCarefully depress the brake pedal and the
beginning and end of a journey.
RMaintain a greater distance to the vehicle
ahead.
Servicing the brakes
!If the red brake warning lamp lights up in
the instrument cluster and you hear a warn-
ing tone while the engine is running, the
brake fluid level may be too low. Observe
additional warning messages in the multi-
function display.
The brake fluid level may be too low due to
brake pad wear or leaking brake lines.
Have the brake system checked immedi-
ately. This work should be carried out at a
qualified specialist workshop.
!A function or performance test should
only be carried out on a 2-axle dynamom-
eter. If you are planning to have the vehicle tested on such a dynamometer, contact an
authorized Mercedes-Benz Center to
obtain further information first. Otherwise,
you could damage the drive train or the
brake system.
!Because ESP®is an automatic system,
the engine and ignition must be switched
off (SmartKey in position 0or 1or Start/
Stop button in position 0or 1) when the
electric parking brake is being tested on a
brake dynamometer (maximum
10 seconds).
Braking triggered automatically by ESP
®
may seriously damage the brake system.
All checks and maintenance work on the
brake system must be carried out at a quali-
fied specialist workshop. Consult a qualified
specialist workshop to arrange this.
Have brake pads installed and brake fluid
replaced at a qualified specialist workshop.
Driving tips195
Driving and parking
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specialist workshop as soon as possible.
Adapt your driving style to the different brak-
ing characteristics.
Driving off-road increases the likelihood of
damage to the vehicle, which, in turn, can lead
to failure of the mechanical assembly or sys-
tems. Adapt your driving style to suit the ter-
rain conditions. Drive carefully. Have damage
to the vehicle rectified immediately at a quali-
fied specialist workshop.
Do not switch to transmission positionN
when driving off-road. If you try to brake the
vehicle using the service brake, you could
lose control of the vehicle. If the gradient is
too steep for your vehicle, drive back down in
reverse gear.
General notes
Read this section carefully before driving your
vehicle off-road. Practice by driving over more
gentle off-road terrain first.
Familiarize yourself with the characteristics
of your vehicle and the gear shift operation
before driving through difficult terrain.
The following driving systems are specially
adapted to off-road driving:
ROff-road program 1 and 2 (vehicles with the
ON&OFFROAD package) (
Ypage 258)
RLOW RANGE off-road gear (vehicles with
the ON&OFFROAD package)
(
Ypage 259)
RDifferential lock (vehicles with the
ON&OFFROAD package) (
Ypage 259)
ROff-road ABS (Ypage 69)
ROff-road 4ETS (Ypage 73)
RAIRMATIC package (vehicle level)
(
Ypage 218)
RDSR (Downhill Speed Regulation)
(
Ypage 257)
Observe the following notes:
RStop the vehicle before starting to drive
along an off-road route.
RSelect a vehicle level that is suitable for the
terrain. To avoid damaging the vehicle, make sure there is always sufficient ground
clearance.
RCheck that items of luggage and loads are
stowed safely and are well secured
(
Ypage 345).
RAlways keep the engine running and in gear
when driving on a downhill gradient. Acti-
vate DSR (
Ypage 257).
RAlways keep the engine running and in gear
when driving on a slope.
RAdapt your speed to the terrain. The
rougher, steeper or more ruts on the ter-
rain, the slower your speed should be.
RDo not jump with the vehicle as this will
interrupt the vehicle's propulsion.
RDrive with extreme care on unfamiliar off-
road routes where visibility is poor. For
safety reasons, get out of the vehicle first
and survey the off-road route.
RLook out for obstacles, such as rocks,
holes, tree stumps and furrows.
RAlways keep the doors, the tailgate, the
side windows and the sliding sunroof
closed while the vehicle is in motion.
RDo not shift the automatic transmission to
transmission position N.
RObserve the notes on off-road fording
(
Ypage 197).
iDo not use the HOLD function when driv-
ing off-road, on steep uphill or downhill gra-
dients or on slippery or loose surfaces. The
HOLD function cannot hold the vehicle on
such surfaces.
Checklist before driving off-road
!If the engine oil warning lamp lights up
while the vehicle is in motion, stop the vehi- cle in a safe place as soon as possible.
Check the engine oil level. The engine oil
warning lamp warning must not be ignored.
Continuing the journey while the symbol is
displayed could lead to engine damage.
XEngine oil level: check the engine oil level
and add oil if necessary.
Driving tips199
Driving and parking
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