2016 MERCEDES-BENZ GL-Class check engine

Engine
ProblemPossible causes/consequences andMSolutions
;
The yellow Check
Engine warning lamp
lights up while the
engine is running.There may be a malfunction, for example:
Rin the engine management
Rin the fuel injection system
Rin the exhaust system
Rin the ignition system (for vehicles with gasoline engines)
Rin the fuel system
The emission limit values may be exceeded and the engine may be
in emergency mode.
XHave the vehicle checked as soon as possible at a qualified
specialist workshop.
iIn some states, you must immediately visit a qualified special-
ist workshop as soon as the yellow Check Engine warning lamp
lights up. This is due to the legal requirements in effect in these
states. If in doubt, check whether such legal regulations apply in the state in which you are currently driving.
Vehicles with a diesel engine: the fuel tank has been run dry
(
Ypage 185).
XStart the engine three to four times after refueling.
If the yellow Check Engine warning lamp goes out, emergency
running mode is canceled. The vehicle need not be checked.
8
The yellow reserve fuel
warning lamp lights up
while the engine is run-
ning.The fuel level has dropped into the reserve range.
XRefuel at the nearest gas station.
8
The yellow reserve fuel
warning lamp flashes
while the vehicle is in
motion.
In addition, the ;
Check Engine warning
lamp may light up.The fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.
XCheck that the fuel filler cap is correctly closed.
XIf the fuel filler cap is not correctly closed: close the fuel filler
cap.
XIf the fuel filler cap is closed: visit a qualified specialist work-
shop.
334Warning and indicator lamps in the instrument cluster
On-board computer and displays

ProblemPossible causes/consequences andMSolutions
?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.The coolant level is too low.
!Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
If the coolant level is correct, the airflow to the engine radiator may
be blocked or the electric engine radiator fan may be malfunc-
tioning.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
XObserve the additional display messages in the multifunction
display.
XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 189).
XLeave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
XCheck the coolant level and add coolant, observing the warning
notes (
Ypage 373).
XIf you have to add coolant frequently, have the engine cooling
system checked.
XMake sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
XDo not start the engine again until the coolant temperature is
below 248 ‡(120 †). Otherwise, the engine could be damaged.
XDrive to the nearest qualified specialist workshop.
XAvoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-and-go traffic.
?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. A warning tone
also sounds.The coolant temperature has exceeded 248 ‡ (120 †). The air-
flow to the engine radiator may be blocked or the coolant level may
be too low.
GWARNING
The engine is not being cooled sufficiently and may be damaged.
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to
catch fire.
Steam from the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury.
336Warning and indicator lamps in the instrument cluster
On-board computer and displays

ProblemPossible causes/consequences andMSolutions
XObserve the additional display messages in the multifunction
display.
XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 189).
XLeave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
XCheck the coolant level and add coolant, observing the warning
notes (
Ypage 373).
XIf you have to add coolant frequently, have the engine cooling
system checked.
XMake sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
XAt coolant temperatures below 248 ‡ (120 †), drive to the
nearest qualified specialist workshop.
XAvoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-and-go traffic.
Driving systems
ProblemPossible causes/consequences and MSolutions
·
The red distance warn-
ing function warning
lamp comes on while
the vehicle is moving. A
warning tone also
sounds.You are approaching a vehicle or a stationary obstacle in your line
of travel at too high a speed.
XBe prepared to brake immediately.
XPay careful attention to the traffic situation. You may have to
brake or take evasive action.
Observe the additional information on DISTRONIC PLUS
(
Ypage 205).
Observe the additional information on PRE‑SAFE
®Brake
(
Ypage 76).
Observe the additional information on the distance warning func-
tion of COLLISION PREVENTION ASSIST (
Ypage 70).
Warning and indicator lamps in the instrument cluster337
On-board computer and displays
Z

!Make sure that the windshield wipers are
not folded away from the windshield. You
could otherwise damage the windshield
wipers or the hood.
XMake sure that the windshield wipers are
turned off.
XPull release lever :on the hood.
The hood is released.
XReach into the gap, pull hood catch han-
dle ;up and lift the hood.
If you lift the hood by approximately 15 in
(40 cm), the hood is opened and held open automatically by the gas-filled strut.
Closing the hood
XLower the hood and let it fall from a height
of approximately 8 in (20 cm).
XCheck that the hood has engaged properly.
If the hood can be raised slightly, it is not
properly engaged. Open it again and close
it with a little more force.
Radiator
Vehicles with a diesel engine: do not cover
the radiator, for example with a winter front or
bug cover. The readings of the on-board-diag-
nostic system may otherwise be inaccurate.
Some of these readings are required by law
and must be accurate at all times.
Engine oil
General notes
Depending on your driving style, the vehicle
consumes up to 0.9 US qt (0.8 liters) of oil per
600 miles (1,000 km). The oil consumption
may be higher than this when the vehicle is
new or if you frequently drive at high engine
speeds.
Depending on the engine, the oil dipstick may
be in a different location.
When checking the oil level:
Rpark the vehicle on a level surface.
Rthe engine should be switched off for
approximately five minutes if the engine is
at normal operating temperature.
Rif the engine is not at normal operating
temperature, e.g. if the engine was only
started briefly, wait about 30 minutes
before carrying out the measurement.
Checking the oil level using the oil dip-
stick
GWARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very hot.
Working in the engine compartment poses a
risk of injury.
Where possible, let the engine cool down and touch only the components described in the
following.
Engine compartment371
Maintenance and care
Z

Example: engine oil capXTurn cap:counter-clockwise and remove
it.
XAdd engine oil.
If the oil level is at or below the MIN mark on
the oil dipstick, add 1.1 US qt (1.0 l)of
engine oil.
XReplace cap :on the filler neck and
tighten clockwise.
Ensure that the cap locks into place
securely.
XCheck the oil level again with the oil dip-
stick (
Ypage 371).
Further information on engine oil
(
Ypage 450).
Additional service products
Checking coolant level
GWARNING
Certain components in the engine compart-
ment, such as the engine, radiator and parts
of the exhaust system, can become very hot.
Working in the engine compartment poses a
risk of injury.
Where possible, let the engine cool down and touch only the components described in the
following.
GWARNING
The engine cooling system is pressurized, par-
ticularly 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.
XPark the vehicle on a level surface.
Only check the coolant level when the vehi-
cle is on a level surface and the engine has
cooled down.
XTurn the SmartKey to position 2in the igni-
tion lock (
Ypage 165).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice (
Ypage 165).
XCheck the coolant temperature gauge in
the multifunction display.
The coolant temperature must be below
158 ‡ (70 †).
XTurn the SmartKey to position 0in the igni-
tion lock (
Ypage 165).
XSlowly turn cap :half a turn counter-
clockwise and allow excess pressure to
escape.
XTurn cap :further counter-clockwise and
remove it.
If the coolant is at the level of marker bar =
in the filler neck when cold, there is enough
coolant in coolant expansion tank ;.
If the coolant level is approximately 0.6 in
(1.5 cm) above marker bar =in the filler
neck when warm, there is enough coolant
in expansion tank ;.
XIf necessary, add coolant that has been tes-
ted and approved by Mercedes-Benz.
XReplace cap:and turn it clockwise as far
as it will go.
Engine compartment373
Maintenance and care
Z

Hiding a service message
XPress the%ora button on the steer-
ing wheel.
Displaying service messages
XSwitch on the ignition.
XPress the =or; button on the steer-
ing wheel to select the Serv.
menu.
XPress the9or: button to select the
ASSYST PLUS
submenu and confirm by
pressing the abutton.
The service due date appears in the multi-
function display.
Information about Service
Resetting the ASSYST PLUS service
interval display
!If the ASSYST PLUS service interval dis-
play has been inadvertently reset, this set-
ting can be corrected at a qualified special-
ist workshop.
Have service work carried out as described
in the Maintenance Booklet. This may oth-
erwise lead to increased wear and damage
to the major assemblies or the vehicle.
A qualified specialist workshop, e.g. an
authorized Mercedes-Benz Center, will reset
the ASSYST PLUS service interval display
after the service work has been carried out.
You can also obtain further information on
maintenance work, for example.
Special service requirements
The specified maintenance interval takes only
the normal operation of the vehicle into
account. Under arduous operating conditions
or increased load on the vehicle, mainte-
nance work must be carried out more fre-
quently, for example:
Rregular city driving with frequent intermedi-
ate stops
Rif the vehicle is primarily used to travel
short distances
Ruse in mountainous terrain or on poor road
surfaces
Rif the engine is often left idling for long peri- ods
Under these or similar conditions, have, for
example, the air filter, engine oil and oil filter
replaced or changed more frequently. Under
arduous operating conditions, the tires must
be checked more often. Further information
can be obtained at a qualified specialist work-
shop, e.g. an authorized Mercedes-Benz Cen-
ter.
Driving abroad
An extensive Mercedes-Benz Service network
is also available in other countries. You can
obtain further information from any author-
ized Mercedes-Benz Center.
Care
General notes
HEnvironmental note
Dispose of empty packaging and cleaning
cloths in an environmentally responsible man-
ner.
!For cleaning your vehicle, do not use any
of the following:
Rdry, rough or hard cloths
Rabrasive cleaning agents
Care375
Maintenance and care
Z

HEnvironmental note
Batteries contain dangerous
substances. It is against the
law to dispose of them with
the household rubbish. They
must be collected separatelyand recycled to protect the
environment.
Dispose of batteries in an
environmentally friendly
manner. Take discharged
batteries to a qualified spe-
cialist workshop or a special
collection point for used bat-
teries.
!Have the battery checked regularly at a
qualified specialist workshop.
Observe the service intervals in the Main-
tenance Booklet or contact a qualified spe-
cialist workshop for more information.
!You should have all work involving the
battery carried out at a qualified specialist
workshop. In the exceptional case that it is
necessary for you to disconnect the battery
yourself, make sure that:
Ryou switch off the engine and remove the
SmartKey. On vehicles with KEYLESS-
GO, ensure that the ignition is switched
off. Check that all the indicator lamps in
the instrument cluster are off. Otherwise, electronic components, such as the
alternator, may be damaged.
Ryou first remove the negative terminal
clamp and then the positive terminal
clamp. Never swap the terminal clamps.
Otherwise, the vehicle's electronic sys-
tem may be damaged.
Rthe transmission is locked in position P
after disconnecting the battery. The vehi-
cle is secured against rolling away. You
can then no longer move the vehicle.
The battery and the cover of the positive
terminal clamp must be installed securely
during operation. Comply with safety precautions and take pro-
tective measures when hand
ling bat
teries.
Risk of explosion.
Fire, open flames and smoking are
prohibited when handling the bat-
tery. Avoid creating sparks.
Battery acid is caustic. Avoid con-
tact with skin, eyes or clothing.
Wear suitable protective clothing,
especially gloves, apron and face-
guard.
Rinse any acid spills immediately
with clear water. Contact a physi-
cian if necessary.
Wear eye protection.
Keep children away.
Observe this Operator's Manual.
For safety reasons, Mercedes-Benz recom-
mends that you only use batteries which have
been tested and approved for your vehicle by
Mercedes-Benz. These batteries provide
increased impact protection to prevent vehi-
cle occupants from suffering acid burns
should the battery be damaged in the event of
an accident.
In order for the battery to achieve the maxi-
mum possible service life, it must always be
sufficiently charged.
The vehicle battery, like other batteries, can
discharge over time if you do not use the
vehicle. In this case, have the battery discon- nected at a qualified specialist workshop. You
can also charge the battery with a charger
recommended by Mercedes-Benz. Contact a
Battery (vehicle)393
Breakdown assistance
Z

qualified specialist workshop for further infor-
mation.
Have the battery condition of charge checked
more frequently if you use the vehicle mainly
for short trips or if you leave it standing idle
for a lengthy period. Consult a qualified spe-
cialist workshop if you wish to leave your
vehicle parked for a long period of time.
Remove the SmartKey if you park the vehicle
and do not require any electrical consumers.
The vehicle will then use very little energy,
thus conserving battery power.
iIf the power supply has been interrupted,
e.g. if you reconnect the battery, you will
have to:
Rset the clock. Information on setting the
clock can be found in the Digital Opera-
tor's Manual.
On vehicles with COMAND and a naviga-
tion system, the clock is set automati-
cally.
Rreset the function for folding the exterior mirrors in/out automatically, by folding
the mirrors out once (
Ypage 125).
Charging the battery
GWARNING
During charging and jump-starting, explosive
gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, open flames, creating
sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting.
Do not lean over a battery.
GWARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with skin, eyes or clothing. Do
not inhale any battery gases. Do not lean over
the battery. Keep children away from batter-
ies. Wash away battery acid immediately with
plenty of clean water and seek medical atten-
tion.
GWARNING
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
ing the vehicle or charging the battery, gases can escape from the battery. There is a risk of
an explosion.
Allow the frozen battery to thaw out before
charging it or jump-starting.
!Only use battery chargers with a maxi-
mum charging voltage of 14.8 V.
!Only charge the battery using the jump-
starting connection point.
If, at low temperatures, the indicator lamps/
warning lamps in the instrument cluster do
not light up, it is highly likely that the dis-
charged battery has frozen. In this case you
may neither jump-start the vehicle nor charge
the battery. The service life of a thawed-out
battery may be shorter. The starting charac-
teristics can be impaired, particularly at low
temperatures. Have the thawed-out battery
checked at a qualified specialist workshop.
Never charge the battery if it is still installed in
the vehicle, unless you use a battery charger
which has been tested and approved by
Mercedes-Benz. A battery charger unit spe-
cially adapted for Mercedes-Benz vehicles
and tested and approved by Mercedes-Benz
is available as an accessory. It permits the
charging of the battery in its installed posi-
tion. Contact an authorized Mercedes-Benz
Center for further information and availabil-
ity. Charge the battery in accordance with the
separate instructions for the battery charger.
The jump-starting connection point is in the
engine compartment (
Ypage 395).
Read the battery charger's operating instruc-
tions before charging the battery.
XOpen the hood.
XConnect the battery charger to the positive terminal and ground point in the same
order as when connecting the donor bat-
tery in the jump-starting procedure
(
Ypage 395).
394Battery (vehicle)
Breakdown assistance