2015 MERCEDES-BENZ CLA-Class engine overheat

Display messages
Possible causes/consequences and
M
MSolutions Service Required
Service Required
Do Do
Not
Not Shift
Shift Gears
Gears
Visit Dealer
Visit Dealer You cannot change the transmission position due to a malfunction.
A warning tone also sounds.
If transmission position Dis selected:
X Drive to a qualified specialist workshop without shifting the
transmission from position D.
If transmission position R,Nor Pis selected:
X Secure the vehicle against rolling away (Y page 160).
X Notify a qualified specialist workshop or breakdown service. Only Shift to 'P' Only Shift to 'P'
when Vehicle is when Vehicle is
Stationary Stationary The vehicle is moving.
X
Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Shift the selector lever to position P.Reversing Not Pos‐ Reversing Not Pos‐
sible Service sible Service
Required Required The automatic transmission is malfunctioning. You cannot back
up.
X Visit a qualified specialist workshop. Transmission Mal‐ Transmission Mal‐
function function The automatic transmission is malfunctioning.
X Visit a qualified specialist workshop. Transmission Mal‐
Transmission Mal‐
function Stop function Stop The automatic transmission is malfunctioning.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 160).
X Consult a qualified specialist workshop. Stop
Stop
Vehicle
Vehicle Shift
Shift
to 'P' Leave
to 'P' Leave
Engine Running Engine Running The automatic transmission has overheated.
X Drive on carefully.
The automatic transmission is available again when the display
message goes out.
If the display message continues to be displayed:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 160).
X Wait until the automatic transmission has cooled down and the
display message has disappeared. Display
messages
243On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions Auxiliary Battery
Auxiliary Battery
Malfunction Malfunction The auxiliary battery for the automatic transmission is no longer
being charged.
X Visit a qualified specialist workshop at the next opportunity.
X Until then, set the selector lever to position Pbefore you switch
off the engine.
X Before leaving the vehicle, apply the electric parking brake. Trans.
Trans.
Oil
OilOverhea‐
Overhea‐
ted Drive on with
ted Drive on with
Care Care AMG vehicles: the transmission oil has overheated.
Manual drive program
Mand the temporarily active manual drive
program are no longer available. The engine power output is
reduced.
X Allow the vehicle to cool down. 4matic Currently 4matic Currently
Unavailable Unavailable 4MATIC has overheated. The vehicle is only driven by the front
wheels.
X Drive on.
The airflow cools 4MATIC more quickly.
When the display message goes out, 4MATIC is available again
and the vehicle is driven by all four wheels. 4matic Inoperative 4matic Inoperative 4MATIC is malfunctioning. The vehicle is only driven by the front
wheels.
X Visit a qualified specialist workshop. N The trunk lid is open.
X Close the trunk lid. M The hood is open.
A warning tone also sounds.
G WARNING
The open hood may block your view when the vehicle is in motion.
There is a risk of an accident.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 160).
X Close the hood. C At least one door is open. A warning tone also sounds.
X Close all the doors. 244
Display
messagesOn-board computer and displays

Problem
Possible causes/consequences and
M
MSolutions ?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.
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 malfunc-
tioning.
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 160).
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 289).
X If you need to add coolant more often than usual, have the
engine coolant 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 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.
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 160).Warning and indicator lamps in the instrument cluster
257On-board computer and displays Z

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.
i Read the information on qualified special-
ist workshops (Y page 24). 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.
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. 286
Engine compartmentMaintenance and care

can deteriorate significantly, e.g. as a result
of aging, soot and fuel deposits. It is therefore
strongly recommended that you carry out reg- ular oil changes using an approved engine oil
with the appropriate SAE classification. 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.
When handling brake fluid, observe the
important safety notes on service products
(Y page 353).
The brake fluid change intervals can be found
in the Maintenance Booklet.
Only use brake fluid approved by Mercedes-
Benz according to MB Approval 331.0.
Information about approved brake fluid can
be obtained at any qualified specialist work-
shop or on the Internet at
http://bevo.mercedes-benz.co m.
i Have the brake fluid regularly replaced at
a qualified specialist workshop and the
replacement confirmed in the Maintenance Booklet. 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.
Further information on coolants can be
found in the Mercedes-Benz Specifications for Service Products, MB BeVo 310.1, e.g.
on the Internet at
http://bevo.mercedes-benz.com. Or con-
tact a qualified specialist 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
replacement confirmed in the Maintenance
Booklet.
Comply with the important safety precautions for service products when handling coolant
(Y page 353).
The coolant is a mixture of water and anti-
freeze/corrosion inhibitor. It performs the
following tasks:
R 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 cool-
ant during operation is approximately 266 ‡
(130 †).
The antifreeze/corrosion inhibitor concentra-
tion 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. Service products and filling capacities
357Technical data Z