2019 MERCEDES-BENZ GLS Overheat

Display messages
Possible causes/consequences and
0050
0050Solutions 00AC
Coolant Too Hot Coolant Too Hot
Stop Vehicle Turn Stop Vehicle Turn
Engine Off Engine Off The coolant is too hot.
A warning tone also sounds.
G WARNING
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.
X Pull over and stop the vehicle safely and switch off the engine, pay-
ing attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 158).
X Wait until the engine has cooled down.
X Make sure that the air supply to the engine radiator is not blocked,
e.g. by snow, slush or ice.
X Do not start the engine again until the display message goes out and
the coolant temperature is below 248 ‡ (120 †). Otherwise, the
engine could be damaged.
X Pay attention to the coolant temperature gauge.
If the temperature increases again: X Visit a qualified specialist workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 248 ‡ (120 †). 003D
See Operator's Man‐ See Operator's Man‐
ual ual The battery is not being charged.
A warning tone also sounds.
Possible causes are:
R a defective alternator
R a torn poly-V-belt
R a malfunction in the electronics
! Do not drive any further. Otherwise the engine may overheat.
X Pull over and stop the vehicle safely and switch off the engine, pay-
ing attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 158).
X Consult a qualified specialist workshop. Display
messages
259On-board computer and displays Z

Warning/
indicator
lamp
0051
0051 Signal type
Possible causes/consequences and 0050 0050Solutions 00AC
0051
The red coolant warning lamp comes on while the engine is running.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator may be blocked or the electric engine radiator fan may be defective.
The coolant is too hot and the engine is no longer being cooled sufficiently.
X Observe the additional display messages in the multifunction display.
X Pull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 158).
X Leave the vehicle and keep a safe distance from the vehicle until the engine has
cooled down.
X Check the coolant level and add coolant, observing the warning notes
(Y page 324).
X If you have to add coolant frequently, have the engine cooling system checked.
X Make sure that the air supply to the engine radiator is not blocked, e.g. by snow,
slush or ice.
X Do not start the engine again until the coolant temperature is below 248 ‡
(120 †). Otherwise, the engine could be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in mountainous terrain
and stop-and-go traffic. 00AC
0051
The red coolant warning lamp comes on while the engine is running.
The coolant temperature has exceeded 248 ‡ (120 †). The airflow to the engine radiator may be blocked or the coolant level may be too low.
G WARNING
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.
X Observe the additional display messages in the multifunction display.
X Pull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 158).
X Leave the vehicle and keep a safe distance from the vehicle until the engine has
cooled down.
X Check the coolant level and add coolant, observing the warning notes
(Y page 324).
X If you have to add coolant frequently, have the engine cooling system checked.
X Make sure that the air supply to the engine radiator is not blocked, e.g. by snow,
slush or ice. 284
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Engine compartment
Hood
Important safety notes G
WARNING
If the hood is unlatched, it may open up when the vehicle is in motion and block your view.
There is a risk of an accident.
Never unlatch the hood while driving. Before
every trip, ensure that the hood is locked. G
WARNING
When opening and closing the hood, it may
suddenly fall into the closed position. There is a risk of injury to persons within range of
movement of the hood.
Open and close the hood only when no one is
within its range of movement. G
WARNING
Opening the hood when the engine is over-
heated or when there is a fire in the engine
compartment could expose you to hot gases
or other service products. There is a risk of
injury.
Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department. G
WARNING
The engine compartment contains moving
components. Certain components, such as
the radiator fan, may continue to run or start
again suddenly when the ignition is off. There is a risk of injury.
If you need to do any work inside the engine
compartment:
R switch off the ignition
R never reach into the area where there is a
risk of danger from moving components,
such as the fan rotation area R
remove jewelry and watches
R keep items of clothing and hair, for exam-
ple, away from moving parts G
WARNING
The ignition system and the fuel injection sys- tem work under high voltage. If you touch
components which are under voltage, you
could get an electric shock. There is a risk of
injury.
Never touch components of the ignition sys-
tem or fuel injection system when the ignition is switched on.
Electrically live components include ignition
coils, spark plug connectors and the test socket. To ensure the flow of fresh air through the air
vents into the vehicle interior, please observe
the following notes (Y page 136):
Opening the hood G
WARNING
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. G
WARNING
When the hood is open and the windshield
wipers are set in motion, you can be injured by the wiper linkage. There is a risk of injury.
Always switch off the windshield wipers and
the ignition before opening the hood.
! Make sure that the windshield wipers are
not folded away from the windshield. You
could otherwise damage the windshield wip-
ers or the hood. Engine compartment
321Maintenance and care Z

X
Make sure that the windshield wipers are
turned off.
X Pull release lever 0043on the hood.
The hood is released. X
Reach into the gap, pull hood catch handle 0044
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 X
Lower the hood and let it fall from a height of
approximately 8 in (20 cm).
X Check 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
Do not cover up the radiator, such as with a
thermal mat or insect protection cover. Other-
wise, the values of the European on-board diag- nostics may be affected. Some of these read-
ings are required by law and must be accurate at all times. Engine oil
Important safety notes G
WARNING
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. G
WARNING
Opening the hood when the engine is over-
heated or when there is a fire in the engine
compartment could expose you to hot gases
or other service products. There is a risk of
injury.
Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department. G
WARNING
If engine oil comes into contact with hot com- ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Make sure that engine oil is not spilled next to
the filler neck. Let the engine cool down and
thoroughly clean the engine oil off the com-
ponents before starting the engine.
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. 322
Engine compartmentMaintenance and care

be used as a temporary measure. Make sure
that you use the proper size and type (sum-
mer or winter tire).
i Vehicles equipped with MOExtended tires
are not equipped with a TIREFIT kit at the fac- tory. It is therefore recommended that you
additionally equip your vehicle with a TIREFIT
kit if you mount tires that do not feature run- flat characteristics, e.g. winter tires. A TIREFIT kit may be obtained from a qualified specialist
workshop.
Important safety notes G
WARNING
When you drive in emergency mode, the han- dling characteristics will be impaired. e.g.
when cornering, when accelerating heavily
and when braking. There is a risk of an acci-
dent.
Do not exceed the maximum permissible
speed for MOExtended tires. Avoid any abrupt
steering and driving maneuver as well as driv-
ing over obstacles (curbs, pot holes, off-road).
This applies, in particular, to laden vehicles.
Stop driving in emergency mode if you notice:
R banging noises
R vehicle vibration
R smoke and the smell of rubber
R continual ESP ®
intervention
R cracks in the tire sidewall
After driving in emergency mode, have the
rims checked by a qualified specialist work-
shop to determine whether they can continue
to be used. The defective tire must be
replaced in every case. TIREFIT kit
Important safety notes TIREFIT is a tire sealant.
You can use TIREFIT to seal punctures of up to
0.16 in (4 mm), particularly those in the tire
tread. You can use TIREFIT at outside tempera-
tures down to 00F84 ‡ (00F820 †). G
WARNING
In the following situations, the tire sealant is
unable to provide sufficient breakdown assis- tance, as it is unable to seal the tire properly:
R there are cuts or punctures in the tire larger
than those mentioned above.
R the wheel rim is damaged.
R you have driven at very low tire pressures or
on a flat tire.
There is a risk of an accident.
Do not drive the vehicle. Contact a qualified
specialist workshop. G
WARNING
The tire sealant is harmful and causes irrita-
tion. It must not come into contact with your
skin, eyes or clothing or be swallowed. Do not inhale TIREFIT fumes. Keep tire sealant away
from children. There is a risk of injury.
If you come into contact with the tire sealant,
observe the following:
R Rinse off the tire sealant from your skin
immediately with water.
R If the tire sealant comes into contact with
your eyes, immediately rinse them thor-
oughly with clean water.
R If tire sealant is swallowed, immediately
rinse your mouth out thoroughly and drink
plenty of water. Do not induce vomiting,
and seek medical attention immediately.
R Immediately change out of clothing which
has come into contact with tire sealant.
R If an allergic reaction occurs, seek medical
attention immediately.
! Do not operate the tire inflation compressor
for longer than eight minutes at a time without a break. It may otherwise overheat.
The tire inflation compressor can be operatedagain once it has cooled down.
Comply with the manufacturer’s safety instruc-
tions on the sticker on the tire inflation com-
pressor. Flat tire
337Breakdown assistance Z

Avoid tire pressures that are too low in all the
tires, including the spare wheel.
Underinflated tires may:
R overheat, leading to tire defects
R adversely affect handling
R wear excessively and/or unevenly
R have an adverse effect on fuel consumption
Overinflated tires G
WARNING
Tires with excessively high pressure can burst
because they are damaged more easily by
road debris, potholes etc. In addition, they
also suffer from irregular wear, which can
severely impair the braking properties and the driving characteristics. There is a risk of an
accident.
Avoid tire pressures that are too high in all the
tires, including the spare wheel.
Overinflated tires may: R increase the braking distance
R adversely affect handling
R wear excessively and/or unevenly
R have an adverse effect on ride comfort
R be more susceptible to damage
Maximum tire pressures 0043
Example: maximum permissible tire pres-
sure
Never exceed the maximum permissible tire
inflation pressure. Always observe the recom-
mended tire pressure for your vehicle when
adjusting the tire pressure (Y page 355).i
The actual values for tires are vehicle-spe-
cific and may deviate from the values in the
illustration. Checking the tire pressures
Important safety notes Observe the notes on tire pressure
(Y
page 355).
Information on air pressure for the tires on your vehicle can be found:
R on the Tire and Loading Information placard
on the B-pillar on the driver's side
R in the tire pressure table in the fuel filler flap
R in the "Tire pressure" section
Checking tire pressures manually To determine and set the correct tire pressure,
proceed as follows:
X Remove the valve cap of the tire that is to be
checked.
X Press the tire pressure gage securely onto the
valve.
X Read the tire pressure and compare it to the
recommended value on the Tire and Loading
Information placard or the tire pressure table
(Y page 355).
X If the tire pressure is too low, increase the tire
pressure to the recommended value.
X If the tire pressure is too high, release air. To
do so, press down the metal pin in the valve,
using the tip of a pen for example. Then check the tire pressure again using the tire pressure
checker.
X Screw the valve cap onto the valve.
X Repeat these steps for the other tires. Tire pressure loss warning system
General notes While the vehicle is in motion, the tire pressure
loss warning system monitors the set tire pres-
sure using the rotational speed of the wheels.
This enables the system to detect significant
pressure loss in a tire. If the speed of rotation of
a wheel changes as a result of a loss of pressure, 358
Tire pressureWheels and tires

Information on tire pressures is displayed in the
multifunction display. After a few minutes of
driving, the current tire pressure of each tire is
shown in the Serv.
Serv. menu of the multifunction
display, see illustration (example). For information on the message display, refer to
the "Checking the tire pressure electronically"
section (Y page 361).
Important safety notes G
WARNING
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the pressure rec-
ommended by the vehicle manufacturer on
the Tire and Loading Information placard on
the driver's door B-pillar or the tire pressure
label on the inside of the fuel filler flap. If your vehicle has tires of a different size than the
size indicated on the Tire and Loading Infor-
mation placard or the tire pressure label, you should determine the proper tire pressure for
those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitoring system (TPMS) that illuminates a low tire pres-
sure telltale when one or more of your tires
are significantly underinflated. Accordingly,
when the low tire pressure telltale illuminates,
you should stop and check your tires as soon
as possible, and inflate them to the proper
pressure. Driving on a significantly underin-
flated tire causes the tire to overheat and can lead to tire failure. Underinflation also
reduces fuel efficiency and tire tread life, andmay affect the vehicle's handling and stop-
ping ability.
Please note that the TPMS is not a substitute
for proper tire maintenance, and it is the driv-
er's responsibility to maintain correct tire pressure, even if underinflation has not
reached the level to trigger illumination of the TPMS low tire pressure telltale.
USA only:
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate if the
system is not operating properly. The TPMS
malfunction indicator is combined with the
low tire pressure telltale. When the system
detects a malfunction, the warning lamp will
flash for approximately a minute and then
remain continuously illuminated. This
sequence will be repeated every time the vehi-
cle is started as long as the malfunction
exists.
When the malfunction indicator is illuminated,
the system may not be able to detect or signal low tire pressure as intended. TPMS malfunc-tions may occur for a variety of reasons,
including the mounting of incompatible
replacement or alternate tires or wheels on
the vehicle that prevent the TPMS from func-
tioning properly. Always check the TPMS mal-
function telltale after replacing one or more
tires or wheels on your vehicle to ensure that
the replacement or alternate tires and wheels
allow the TPMS to continue to function prop-
erly.
It is the driver's responsibility to set the tire
pressure to that recommended for cold tires
which is suitable for the operating situation
(Y page 355). Note that the correct tire pressure
for the current operating situation must first be
taught-in to the tire pressure monitor. If a sub-
stantial loss of pressure occurs, the warning
threshold for the warning message is aligned to the taught-in reference values. Restart the tire
pressure monitor after adjusting the pressure of
the cold tires (Y page 362). The current pres-
sures are saved as new reference values. As a
result, a warning message will appear if the tire
pressure drops significantly.
The tire pressure monitor does not warn you of
an incorrectly set tire pressure. Observe the
notes on the recommended tire pressure
(Y page 355).
The tire pressure monitor is not able to warn you of a sudden loss of pressure, e.g. if the tire is
penetrated by a foreign object. In the event of a 360
Tire pressureWheels and tires

Restarting the tire pressure monitor
When you restart the tire pressure monitor, all
existing warning messages are deleted and the
warning lamps go out. The monitor uses the cur-
rently set tire pressures as the reference values
for monitoring. In most cases, the tire pressure
monitor will automatically detect the new refer- ence values after you have changed the tire
pressure. However, you can also set reference
values manually as described here. The tire
pressure monitor then monitors the new tire
pressure values.
X Set the tire pressure to the value recommen-
ded for the corresponding driving situation on the Tire and Loading Information placard on
the driver's side B-pillar (Y page 355).
You can find more tire pressure values for
various operating conditions in the tire pres-
sure table inside the fuel filler flap
(Y page 356).
X Make sure that the tire pressure is correct on
all four wheels.
X Make sure that the SmartKey is in position 0048
in the ignition lock.
X Press the 0059or0065 button on the steering
wheel to select the Serv.
Serv. menu.
X Press the 0063or0064 button to select
Tire Pressure Tire Pressure .
X Press 0076.
The multifunction display shows the current
tire pressure for the individual tires or the
Tire pressure will be displayed
Tire pressure will be displayed
after driving a few minutes
after driving a few minutes message.
X Press the 0064button.
The Use
Use Current
Current Pressures
Pressures as
asNew
New Ref‐
Ref‐
erence
erence Values
Valuesmessage appears in the mul-
tifunction display.
If you wish to confirm the restart:
X Press the 0076button.
The Tire
Tire Press.
Press. Monitor
Monitor Restarted
Restarted mes-
sage appears in the multifunction display.
After driving for a few minutes, the system
checks whether the current tire pressures are
within the specified range. The new tire pres- sures are then accepted as reference values
and monitored.
If you wish to cancel the restart: X Press the 0038button.
The tire pressure values stored at the last
restart will continue to be monitored. Radio type approval for the tire pres-
sure monitor Country Radio type approval number
USA FCC ID: MRXGG4
FCC ID: MRXMC34MA4
This device complies with Part 15
of the FCC Rules. Operation is
subject to the following two con- ditions: (1) This device may not
cause harmful interference, and
(2) This device must accept any
interference received, including
interference that may cause
undesired operation. Canada IC: 2546A-GG4;
IC: 2546A- MC34MA4;
Le présent appareil est conforme
aux CNR d'Industrie Canada
applicables aux appareils radio
exempts de license. L'exploita-
tion est autorisée aux deux con-
ditions suivantes: (1) l'appareil
ne doit pas produire de brouil-
lage, et (2) l'utilisateur de l'ap-
pareil doit accepter tout brouil-
lage radioélectrique subi, même
si le brouillage est susceptible
d'en compromettre le fonc-
tionnement. Loading the vehicle
Instruction labels for tires and loads
G
WARNING
Overloaded tires can overheat, causing a
blowout. Overloaded tires can also impair the steering and driving characteristics and lead
to brake failure. There is a risk of accident.
Observe the load rating of the tires. The load
rating must be at least half of the GAWR of
your vehicle. Never overload the tires by
exceeding the maximum load.
Two instruction labels on your vehicle show the maximum possible load.
(1) The Tire and Loading Information placard is on the B-pillar on the driver's side. The Tire 362
Loading the vehicleWheels and tires