2017 MERCEDES-BENZ CLA engine

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.
! Make sure that the windshield wipers are
not folded away from the windshield. You
could otherwise damage the windshield wip-
ers or the hood.254
Engine compartment
Maintenance and care

Checking and adding other service
products
Checking coolant level
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 gloves and eye protection. Slowly
open the cap to relieve pressure.
! The coolant may only be checked and cor-
rected when the engine is cool (coolant tem-
perature below 104 ‡ (40 †) . Checking the
coolant when the coolant temperature is
above 104 ‡ (40 †) ma y result in damage to
th e engin e or to th e engin e coolin g system.
X
Par k th e vehicl e on a level surface.
Only chec k th e coolan t level when th e vehicl e
is on a level surfac e and th e engin e has cooled
down .X
Turn th e SmartKey to position 2 in th e ignition
loc k ( Y
page 121).X
Chec k th e coolan t temperature display in th e
instrumen t cluster.
The coolan t temperature mus t be belo w
10 4 ‡ (40 †) .X
Turn the SmartKey to position 0 ( Y
page 12 1)
in the ignition lock. X
Slowly turn cap C counter-clockwise and to
relieve excess pressure. X
Turn cap C further counter-clockwise and
remove it.
If the coolant is at the level of marker bar

X
Make sure that the vehicle is stationary and
that the SmartKey is in position 2 in the igni-
tion lock. X
Open the camera cover for cleaning via the
multimedia system (see the separate operat-
ing instructions). X
To clean the rear view camera: use clear
water and a soft cloth to clean camera
lens C .
Cleaning the exhaust pipes
G WARNING
The exhaust tail pipe and tail pipe trim can
become very hot. If you come into contact
with these parts of the vehicle, you could burn
yourself. There is a risk of injury.
Always be particularly careful around the
exhaust tail pipe and the tail pipe trim. Allow
these components to cool down before touch-
ing them.
! Do not clean the exhaust pipe with acid-
based cleaning agents, such as bathroom
cleaner or wheel cleaner.
! Mercedes-AMG vehicles with black exhaust
pipes: the black-chrome tailpipe finishers
should not be polished with a chrome polish.
They will otherwise lose their black sheen. For
optimal care, the faceplates should be rubbed
with a lightly oiled cloth after every car wash.
Commercially available engine and care oils
are suitable for this.
For heavier soiling, you can apply a fine paint-
work polish with a microfiber cloth. Remove
the excess polish residue after polishing.
Impurities combined with the effects of road grit
and corrosive environmental factors may cause
flash rust to form on the surface. You can restore the original shine of the exhaust pipe by
cleaning it regularly, especially in winter and
after washing. X
Clean the exhaust pipe with a care product
tested and approved by Mercedes-Benz.
Interior care
Cleaning the display
! For cleaning, do not use any of the following: R
alcohol-based thinner or gasoline R
abrasive cleaning agents R
commercially-available household cleaning
agents
These may damage the display surface. Do
not put pressure on the display surface when
cleaning. This could lead to irreparable dam-
age to the display. X
Before cleaning the display, make sure that it
is switched off and has cooled down. X
Clean the display surface using a commer-
cially available microfiber cloth and TFT/LCD
display cleaner. X
Dry the display surface using a dry microfiber
cloth.
Cleaning the plastic trim
G WARNING
Care products and cleaning agents containing
solvents cause surfaces in the cockpit to
become porous. As a result, plastic parts may
come loose in the event of air bag deploy-
ment. There is a risk of injury.
Do not use any care products and cleaning
agents to clean the cockpit.
! Do not affix the following to plastic surfaces: R
stickers R
films R
scented oil bottles or similar items
You can otherwise damage the plastic.
! Do not allow cosmetics, insect repellent or
sunscreen to come into contact with the plas-
tic trim. This maintains the high-quality look of
the surfaces. Care 263
Maintenance and care Z

X
Make sure that the engine cannot be started
via your smartphone ( Y
page 122).X
Make sure that the passengers are not endan-
gered as they do so. Make sure that no one is
near the danger area while a wheel is being
changed. Anyone who is not directly assisting
in the wheel change should, for example,
stand behind the barrier. X
Get out of the vehicle. Pay attention to traffic
conditions when doing so. X
Close the driver's door.
MOExtended tires (tires with run-flat
properties)
General notes With MOExtended tires (tires with run flat char-
acteristics), you can continue to drive your vehi-
cle even if there is a total loss of pressure in one
or more tires. The affected tire must not show
any clearly visible damage.
You can recognize MOExtended tires by the
MOExtended marking which appears on the
sidewall of the tire. You will find this marking
next to the tire size designation, the load-bear-
ing capacity and the speed index ( Y
page 296).
MOExtended tires may be used only in conjunc-
tion with an activated tire pressure loss warning
system (Canada only) or tire pressure monitor
(USA only).
If a pressure loss warning message appears
in the multifunction display: R
observe the instructions in the display mes-
sages ( Y
page 209).R
check the tire for damage. R
if driving on, observe the following notes.
The driving distance possible in run-flat mode is
approximately 50 miles (80 km) when the vehi-
cle is partially laden. When the vehicle is fully
laden it is approximately 19 miles (30 km).
In addition to the vehicle load, the driving dis-
tance possible depends upon: R
Vehicle speed R
Road condition R
Outside temperature
The driving distance possible in run-flat mode
may be reduced by extreme driving conditions
or maneuvers, or it can be increased through a
moderate style of driving. The driving distance possible in run-flat mode is
counted from the moment the tire pressure loss
warning appears in the multifunction display.
You must not exceed a maximum speed of
50 mph (80 km/h).
When replacing one or all tires, please observe
the following specifications for your vehicle's
tires: R
size R
type and R
the "MOExtended" marking
If a tire has gone flat and cannot be replaced
with a MOExtended tire, a standard tire may be
used as a temporary measure. Make sure that
you use the proper size and type (summer or
winter tire).
Vehicles equipped with MOExtended tires are
not equipped with a TIREFIT kit at the factory. It
is therefore recommended that you additionally
equip your vehicle with a TIREFIT kit if you mount
tires that do not feature run-flat properties, e.g.
winter tires. A TIREFIT kit may be obtained from
a qualified specialist workshop.
Important safety notes
G WARNING
When driving in emergency mode, the driving
characteristics deteriorate, e.g. when corner-
ing, accelerating quickly and when braking.
There is a risk of an accident.
Do not exceed the stated maximum speed.
Avoid abrupt steering and driving maneuvers,
and driving over obstacles (curbs, potholes,
off-road). This applies in particular to a laden
vehicle.
Stop driving in emergency mode if: R
you hear banging noises. R
the vehicle starts to shake. R
you see smoke and smell rubber. R
ESP ®
is intervening constantly. R
there are tears in the sidewalls of the tire.
After driving in emergency mode, have the
wheel rims checked at a qualified specialist
workshop with regard to their further use. The
defective tire must be replaced in every case. Flat tire 267
Breakdown assistance Z

Battery (vehicle)
Important safety notes Special tools and expert knowledge are required
when working on the battery, e.g. removal and
installation. You should therefore have all work
involving the battery carried out at a qualified
specialist workshop.
G WARNING
Work carried out incorrectly on the battery
can lead, for example, to a short circuit and
thus damage the vehicle electronics. This can
lead to function restrictions applying to
safety-relevant systems, e.g the lighting sys-
tem, the ABS (anti-lock braking system) or the
ESP ®
(Electronic Stability Program). The oper-
ating safety of your vehicle may be restricted.
You could lose control of the vehicle, for
example: R
when braking R
in the event of abrupt steering maneuvers
and/or when the vehicle's speed is not
adapted to the road conditions
There is a risk of an accident.
In the event of a short circuit or a similar inci-
dent, contact a qualified specialist workshop
immediately. Do not drive any further. You
should have all work involving the battery car-
ried out at a qualified specialist workshop.
For further information about ABS and ESP ®
,
see ( Y
page 60) and ( Y
page 63).
G WARNING
Electrostatic build-up can lead to the creation
of sparks, which could ignite the highly explo-
sive gases of a battery. There is a risk of an
explosion.
Before handling the battery, touch the vehicle
body to remove any existing electrostatic
build-up.
The highly flammable gas mixture forms when
charging the battery as well as when jump-start-
ing. Always make sure that neither you nor the bat-
tery is electrostatically charged. A build-up of
electrostatic charge can be caused, for exam-
ple: R
by wearing clothing made from synthetic
fibers R
due to friction between clothing and seats R
if you push or pull the battery across the car-
pet or other synthetic materials R
if you rub the battery with a cloth
G WARNING
During the charging process, a battery produ-
ces hydrogen gas. If a short circuit occurs or
sparks are created, the hydrogen gas can
ignite. There is a risk of an explosion. R
Make sure that the positive terminal of a
connected battery does not come into con-
tact with vehicle parts. R
Never place metal objects or tools on a bat-
tery. R
It is important that you observe the descri-
bed order of the battery terminals when
connecting and disconnecting a battery. R
When jump-starting, make sure that the
battery poles with identical polarity are
connected. R
It is particularly important to observe the
described order when connecting and dis-
connecting the jumper cables. R
Never connect or disconnect the battery
terminals while the engine is running.
G WARNING
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.
H Environmental note
Batteries contain dangerous
substances. It is against the
law to dispose of them withBattery (vehicle) 271
Breakdo wn assis tance Z

the household rubbish. They
must be collected separately
and 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 Mainte-
nance Booklet or contact a qualified specialist
workshop for more information.
! You should have all work involving the bat-
tery carried out at a qualified specialist work-
shop. In the exceptional case that it is neces-
sary for you to disconnect the battery your-
self, make sure that: R
you switch off the engine and remove the
key. 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 com-
ponents, such as the alternator, may be
damaged. R
you first remove the negative terminal
clamp and then the positive terminal
clamp. Never swap the terminal clamps.
Otherwise, the vehicle's electronic system
may be damaged. R
in vehicles with automatic transmission,
the transmission is locked in position P
after disconnecting the battery. The vehicle
is s ecured against rolling away. You can
th
en no longer move the vehicle.
The battery and the cover of the positive ter-
minal clamp must be installed securely during
operation.
Comply with safety precautions and take pro-
tective measures when handling batteries. Risk of explosion.
Fire, open flames and smoking are
prohibited when handling the bat-
tery. Avoid creating sparks.
Battery acid is caustic. Avoid contact
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 physician
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 vehicle
occupants from suffering acid burns should the
battery be damaged in the event of an accident.
In order for the battery to achieve the maximum
possible service life, it must always be suffi-
ciently charged.
Like other batteries, the vehicle battery may
discharge over time if you do not use the vehicle.
In this case, have the battery disconnected at a
qualified specialist workshop. You can also
charge the battery with a charger recommended
by Mercedes-Benz. Contact a qualified special-
ist workshop for further information.
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 specialist
workshop if you wish to leave your vehicle
parked for a long period of time.
Only replace a battery with a battery that has
been recommended by Mercedes-Be nz.272
Battery (vehicle)
Breakdown assistance

G WARNING
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 ven-
tilation while charging and jump-starting. Do not lean over a battery.
G WARNING
During the charging process, a battery produces hydrogen gas. If a short circuit occurs or sparks
are created, the hydrogen gas can ignite. There is a risk of an explosion. R
Make sure that the positive terminal of a connected battery does not come into contact with
vehicle parts. R
Never place metal objects or tools on a battery. R
It is important that you observe the described order of the battery terminals when connecting
and disconnecting a battery. R
When jump-starting, make sure that the battery poles with identical polarity are connected. R
It is particularly important to observe the described order when connecting and disconnecting
the jumper cables. R
Never connect or disconnect the battery terminals while the engine is running.
G WARNING
A discharged battery can freeze at temperatures below freezing point. When jump-starting 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.
! Avoid repeated and lengthy starting attempts. Otherwise, the catalytic converter could be
damaged by the non-combusted fuel.
If the indicator/warning lamps do not light up in the instrument cluster at low temperatures, it is very
likely that the discharged battery has frozen. In this case you may neither jump-start the vehicle nor
charge the battery. Let the battery thaw first. The service life of a thawed-out battery may be shorter.
The starting characteristics can be impaired, particularly at low temperatures. Have the thawed-out
battery checked at a qualified specialist workshop.
Do not start the vehicle using a rapid charging device. If your vehicle's battery is discharged, the
engine can be jump-started from another vehicle or from a second battery using jumper cables.
Observe the following points: R
The battery is not accessible in all vehicles. If the other vehicle's battery is not accessible, jump-
start the vehicle using a second battery or a jump-starting device. R
You may only jump-start the vehicle when the engine and exhaust system are cold. R
Do not start the engine if the battery is frozen. Let the battery thaw first. R
Only jump-start from batteries with a 12 V voltage rating. R
Only use jumper cables that are not damaged and have a sufficient cross-section and insulated
terminal clamps. R
Make sure that the two vehicles do not touch.274
Jump-starting
Breakdown assistance

Make sure that: R
The jumper cables are not damaged. R
Non-insulated parts of the terminal clamps do not come into contact with other metal parts while
the jumper cables are connected to the battery R
The jumper cables cannot come into contact with parts that can move when the engine is running,
such as the V-belt pulley or the fan X
Secure the vehicle by applying the electric parking brake. X
Shift the transmission to position P .X
Turn the SmartKey to position 0 in the ignition lock and remove it.X
Switch off all electrical consumers, e.g. rear window defroster, lighting, etc. X
Open the hood.
Position number