2019 MERCEDES-BENZ GLS SUV coolant temperature

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 00B6
0051
The yellow reserve fuel warning lamp flashes while the vehicle is in motion.
In addition, the 00B9Check Engine warning lamp may light up.
The fuel filler cap is not closed correctly or the fuel system is leaking.
X Check that the fuel filler cap is correctly closed.
X If the fuel filler cap is not correctly closed: close the fuel filler cap.
X If the fuel filler cap is closed: visit a qualified specialist workshop.00AC
0051
The red coolant warning lamp lights up while the engine is running and the
coolant temperature gage is at the start of the scale.
The temperature sensor for the coolant temperature gage is malfunctioning.
The coolant temperature is no longer being monitored. There is a risk of engine
damage if the coolant temperature is too high.
X Pull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions. Do not continue driving under any circumstances.
X Secure the vehicle against rolling away (Y page 158).
X Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
283On-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

Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions X
At coolant temperatures below 248 ‡ (120 †), 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. Driving systems
Warning/
indicator
lamp
0051 0051
Signal type
Possible causes/consequences and 0050
0050Solutions 00BA
0051
The red distance warning lamp lights up while the vehicle is in motion. A warning
tone also sounds.
You are approaching a vehicle, a pedestrian or a stationary obstacle in your line of travel at too high a speed.
X Be prepared to brake immediately.
X Pay careful attention to the traffic situation. You may have to brake or take
evasive action.
Further information about Active Distance Assist DISTRONIC (Y page 172).
Further information on the distance warning function of Active Brake Assist
(Y page 67).
Further information on the distance warning function of Active Brake Assist with
cross-traffic function (Y page 72). Warning and indicator lamps in the instrument cluster
285On-board computer and displays Z

Where possible, let the engine cool down and
touch only the components described in the
following. G
WARNING
The cooling system is pressurized, particularly when the motor is warm. If you open the cap, you could be scalded if hot coolant sprays out.
There is a risk of injury.
Let the engine cool down before you open the
cap. Wear protective gloves and protective
eyewear when opening. Open the cap slowly
to release pressure.
The coolant level may only be checked and cool- ant refilled when the engine and engine coolingsystem have cooled down. G
WARNING
Windshield washer concentrate is highly flam- mable. If windshield washer concentrate getsonto hot components of the engine or the
exhaust system, it can ignite. There is a risk of
fire and injury.
Make sure that windshield washer concen-
trate is not spilled in the vicinity of the filler
neck.
Checking coolant level X
Park the vehicle on a level surface.
Only check the coolant level when the vehicle
is on a level surface and the engine has cooled
down.
X Turn the SmartKey to position 0048in the igni-
tion lock (Y page 140).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice (Y page 142).X
Check the coolant temperature gauge in the
multifunction display.
The coolant temperature must be below
158 ‡ (70 †).
X Turn the SmartKey to position in the ignition
lock 0092(Ypage 140).
X On vehicles with KEYLESS-GO, press the
Start/Stop button (Y page 142).
X Press the Start/Stop button (Y page 142).
X Slowly turn cap 0043half a turn counter-clock-
wise and allow excess pressure to escape.
X Turn cap 0043further counter-clockwise and
remove it.
If the coolant is at the level of marker bar 0087
in the filler neck when cold, there is enough
coolant in coolant expansion tank 0044.
If the coolant level is approximately 0.6 in
(1.5 cm) above marker bar 0087in the filler neck
when warm, there is enough coolant in expan- sion tank 0044.
X If necessary, add coolant that has been tested
and approved by Mercedes-Benz.
X Replace cap 0043and turn it clockwise as far as
it will go.
For further information on coolant, see
(Y page 387).
Adding washer fluid to the windshield
washer system Example: washer fluid reservoir
X To open: pull cap0043upwards by the tab.
X Add the premixed washer fluid.
X To close: press cap 0043onto the filler neck
until it engages.
If the washer fluid level drops below the recom- mended minimum of 1 liter, a message appears in the multifunction display prompting you to
add washer fluid (Y page 273).324
Engine compartmentMaintenance and care

Move the power washer nozzle around when
cleaning your vehicle.
The water temperature of the power washer
must not exceed 140 ‡ (60 †).
Cleaning the paintwork !
Do not affix:
R stickers
R films
R magnetic plates or similar items
to painted surfaces. You could otherwise
damage the paintwork.
Scratches, corrosive deposits, areas affected by
corrosion and damage caused by inadequate
care cannot always be completely repaired. In
such cases, visit a qualified specialist workshop.
X Remove dirt immediately, where possible,
while avoiding rubbing too hard.
X Soak insect remains with insect remover and
rinse off the treated areas afterwards.
X Soak bird droppings with water and rinse off
the treated areas afterwards.
X Remove tree resin, oils, fuels and greases by
rubbing gently with a cloth soaked in petro-
leum ether or lighter fluid
X Remove coolant and brake fluid with a moist
cloth and clear water.
X Use tar remover to remove tar stains.
X Use silicone remover to remove wax.
If water no longer forms "beads" on the paint
surface, use the paint care products recommen- ded and approved by Mercedes-Benz. This is the
case approximately every three to five months,
depending on the climate conditions and the
care product used.
If dirt has penetrated the paint surface or if the
paint has become dull, the paint cleaner recom-
mended and approved by Mercedes-Benz
should be used.
Do not use these care products in the sun or on the hood while the hood is hot.
X Use a suitable touch-up stick, e.g. MB Touch-
Up Stick, to repair slight damage to the paint- work quickly and provisionally.
Matte finish care !
Never polish the vehicle or the light alloy
wheels. Polishing causes the finish to shine. !
The following can give the paint a glossy
appearance and thus reduce the matt effect:
R Rubbing hard with unsuitable agents
R Washing the vehicle in direct sunlight
! Never use paint cleaner, buffing or polishing
products, or gloss preserver, e.g. wax, for the purpose of paintwork care. These products
are only suitable for high-gloss surfaces. Their
use on vehicles with matte paintwork leads to
considerable surface damage or, more spe-
cifically, to shiny, spotted areas.
Always have paintwork repairs carried out at a
qualified specialist workshop.
! Only use automatic car washes which cor-
respond to the latest technological stand-
ards. Never use wash programs which finish
by treating the vehicle with hot wax.
Observe these notes if your vehicle has a clear
matte finish. This will help you to avoid damage
to the paintwork due to incorrect treatment.
These notes also apply to light alloy wheels with
a clear matte finish.
i Use only insect remover and car shampoo
from the range of recommended and
approved Mercedes-Benz care products.
Cleaning the decorative film !
The following may have an effect on the ser-
vice life and color of decorative film:
R sunlight
R temperature, e.g. hot-air fan
R weather conditions
R stone impacts and dirt
R chemical cleaning agents
R greasy substances
! Do not use any types of polish on matt dec-
orative film. Polishing surfaces covered with
film gives it a shiny finish.
! Do not treat matt or structured decorative
film with wax. This may lead to marks that
cannot be removed.
Observe the notes in the matte finish paintwork
care and treatment chapter (Y page 328).
These notes also apply for matte decorative
films.
To clean, use plenty of water and a mild cleaning
agent without additional or abrasive products, 328
CareMaintenance and care

Model MB-Freigabe or
MB-Approval All models
229.5, 229.6
Mercedes‑AMG vehicles
229.5
Mercedes-AMG vehicles:
only use SAE 0W-40
or SAE 5W-40 engine oils.
i MB approval is indicated on the oil contain-
ers.
Filling capacities The following values refer to an engine oil
change, including the oil filter.
Model Capacity
GLS 550 4MATIC
Mercedes‑AMG
vehicles
9.0 US qt (8.5
l) All ot
her models 7.4 US qt (7.0
l) Ad
ditives !
Do not use any additives in the engine oil.
This could damage the engine. Brake fluid
G
WARNING
The brake fluid constantly absorbs moisture
from the air. This lowers the boiling point of
the brake fluid. If the boiling point of the brake fluid is too low, vapor pockets may form in the brake system when the brakes are applied
hard. This would impair braking efficiency.
There is a risk of an accident.
You should have the brake fluid renewed at
the specified intervals.
Comply with the important safety notes for ser- vice products when handling brake fluid
(Y page 384).
Use only brake fluid approved for Mercedes-
Benz according to MB-Freigabeor MB-Approval
331.0.
Information about approved brake fluid can be
obtained at any qualified specialist workshop or on the Internet at
http://bevo.mercedes-benz.com.
i Have the brake fluid regularly replaced at a
qualified specialist workshop in accordance
with the replacement intervals and the
replacement confirmed in the service report. Coolant
Important safety notes G
WARNING
If antifreeze comes into contact with hot com- ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Let the engine cool down before you add anti-
freeze. Make sure that antifreeze is not spilled
next to the filler neck. Thoroughly clean the
antifreeze from components before starting
the engine.
! Only add coolant that has been premixed
with the desired antifreeze protection. You
could otherwise damage the engine.
You can find additional notes on the coolant in
the following places:
R in the Mercedes-Benz Specifications for
Service Products, MB BeVo 310.1
- on the Internet at
http://bevo.mercedes-benz.com
- on the Mercedes-Benz BeVo app
R a qualified specialized workshop
! Always use a suitable coolant mixture, even
in countries where high temperatures prevail.
Otherwise, the engine cooling system is not
sufficiently protected from corrosion and
overheating.
i Have the coolant regularly replaced at a
qualified specialist workshop and the replace- ment confirmed in the service report.
Comply with the important safety notes for ser- vice products when handling coolant
(Y page 384). Service products and filling capacities
387Technical data Z

The coolant is a mixture of water and anti-
freeze/corrosion inhibitor. It is responsible for
the following:
R anti-corrosion protection
R antifreeze protection
R raising the boiling point
If the coolant has antifreeze protection down to -35 ‡ (-37 †), the boiling point of the coolant
during operation is approximately 266 ‡
(130 †).
The antifreeze concentrate/corrosion inhibitor
concentration in the engine cooling system
should:
R be at least 50%. This will protect the engine
cooling system against freezing down to
approximately -35 ‡ (-37 †).
R not exceed 55% (antifreeze protection down
to -49 ‡[-45 †]). Otherwise, heat will not be
dissipated as effectively.
Mercedes-Benz recommends an antifreeze/
corrosion inhibitor concentrate in accordance
with MB Specifications for Service Products
310.1.
i When the vehicle is first delivered, it is filled
with a coolant mixture that ensures adequate
antifreeze and anti-corrosion protection.
i The coolant is checked at specified intervals
at a qualified specialist workshop.
Filling capacities Model Capacity
Mercedes
‑AMG
vehicles Approx. 11.9 US qt
(11.3 l) GLS 550 4MATIC
Approx. 12.0 US qt
(11.4 l) All other models
Approx. 10.3 US qt
(9.7 l) Windshield washer system
Important safety notes G
WARNING
Windshield washer concentrate is highly flam- mable. If windshield washer concentrate getsonto hot components of the engine or the exhaust system, it can ignite. There is a risk of
fire and injury.
Make sure that windshield washer concen-
trate is not spilled in the vicinity of the filler
neck.
! Only MB SummerFit and MB WinterFit
washer fluid should be mixed together. The
spray nozzles may otherwise become
blocked.
Do not use distilled or de-ionized water. Other-
wise, the level sensor may give a false reading.
When handling washer fluid, observe the impor- tant safety notes on service products
(Y page 384).
At temperatures above freezing:
X Fill the washer fluid reservoir with a mixture of
water and windshield washer fluid, e.g. MB
SummerFit.
Add 1 part MB SummerFit to 100 parts water.
At temperatures below freezing:
X Fill the washer fluid reservoir with a mixture of
water and washer fluid, e.g. MB WinterFit.
For the correct mixing ratio refer to the infor- mation on the antifreeze reservoir.
i Add windshield washer fluid, e.g. MB Sum-
merFit or MB WinterFit, to the washer fluid all
year round. Climate control syste
m refrigerant
Important safety notes The climate control system of your vehicle is fil-
led with refrigerant R‑134a.
The instruction label regarding the refrigerant
type used can be found on the radiator cross
member.
! Only the refrigerant R‑134a and the PAG oil
approved by Mercedes-Benz may be used.
The approved PAG oil may not be mixed with
any other PAG oil that is not approved for
R-134a refrigerant. Otherwise, the climate
control system may be damaged.
Service work, such as refilling with refrigerant or
replacing component parts, may only be carried out by a qualified specialist workshop. All appli- 388
Service products and filling capacitiesTechni
cal data