ignition MERCEDES-BENZ CLA 2017 Workshop Manual

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

ASSYST PLUS
Service message The ASSYS T PLU S servic e interval display
inform s you of th e next servic e due date.
You can fin d information on th e typ e of servic e
and servic e intervals in th e Maintenance Book -
let .
You can obtain further information from an
authorize d Mercedes-Benz Cente r or at
http://www.mbusa.co m (US A only).
i The ASSYS T PLU S servic e interval display
does no t sho w any information on th e engin e
oil level. Observ e th e note s on th e engin e oil
level ( Y
page 255).
The multifunction display shows a servic e mes -
sage for several seconds, e.g. :R
Servic e A in .. day sR
Servic e A dueR
Servic e A overdu e by .. day s
Dependin g on th e operating condition s of th e
vehicle, th e remaining time or distanc e until th e
next servic e due dat e is displayed.
The lette r A or B , possibl y in connection wit h a
number or another letter, indicates th e typ e of
service. A stand s for a minor servic e and B for a
major service.
You can obtain further information from an
authorize d Mercedes-Benz Center.
The ASSYS T PLU S servic e interval display does
no t tak e int o accoun t any periods of time during
whic h th e battery is disconnected.
Maintainin g th e time-dependen t servic e sched-
ule: X
Not e down th e servic e due dat e displayed in
th e multifunction display before disconnect -
ing th e battery.
or X
Afte r reconnecting th e battery, subtrac t th e
battery disconnection periods from th e ser -
vic e dat e shown on th e display.
Hiding a service message X
Press th e v or 8 butto n on th e steering
wheel. Displaying service messages X
Switc h on th e ignition .X
Press th e Y or e butto n to select th e
Serv. menu. X
Press th e c or d butto n to select th e
ASSYST PLU S submen u and confirm by press-
ing th e v button.
The servic e due dat e appear s in th e multi-
function display.
Infor ma ti on about Service
Resetting the ASSYST PLUS service
interval display
! If th e ASSYS T PLU S servic e interval display
has been inadvertentl y reset , this setting can
be correcte d at a qualified specialist work-
shop.
Hav e servic e wor k carrie d out as described in
th e Maintenance Booklet . This may otherwise
lead to increased wear and damag e to th e
major assemblies or th e vehicle.
A qualified specialist workshop , e.g. an author-
ized Mercedes-Benz Center, will reset th e
ASSYS T PLU S servic e interval display after th e
servic e wor k has been carrie d out . You can also
obtain further information on maintenance
work, for example.
Special service requirements The specifie d maintenance interval takes only
th e normal operation of th e vehicl e int o
account. Under arduous operating condition s or
increased load on th e vehicle, maintenance
wor k mus t be carrie d out mor e frequently, for
example: R
regular cit y drivin g wit h frequen t intermediat e
stops R
if th e vehicl e is primarily used to travel short
distances R
use in mountainous terrain or on poor road
surfaces R
if th e engin e is often lef t idlin g for lon g periodsR
in particularly dust y conditions, or if air-recir-
culation mod e is frequentl y used
In these or similar operating conditions, hav e
th e interior filter, engin e air cleaner, engin e oil
and oil filter, for example, changed mor e fre-258
ASSYST PLUS
Maintenance and care

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 may cause the paint to
become shiny and thus reduce the matte
effect: R
strong rubbing of the paintwork with
unsuitable materials R
frequent use of automatic car washes 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.
! Do not use wash programs with a hot wax
treatment under any circumstances.
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.
The vehicle should ideally be washed by hand
using a soft sponge, car shampoo and plenty of
water.
Use only insect remover and car shampoo from
the range of approved Mercedes-Benz care
products. Cleaning the vehicle parts
Cleaning the wheels
G WARNING
The water jet from a circular jet nozzle (dirt
blasters) can cause invisible exterior damage
to the tires or chassis components. Compo-
nents damaged in this way may fail unexpect-
edly. There is a risk of an accident.
Do not use power washers with circular jet
nozzles to clean the vehicle. Have damaged
tires or chassis components replaced imme-
diately.
! Do not use acidic wheel cleaning products
to remove brake dust. This could damage
wheel bolts and brake components.
! Do not park your vehicle for a long period of
time directly after cleaning, particularly after
cleaning the wheel rim with wheel cleaner.
Wheel cleaner can lead to the increased cor-
rosion of the brake discs and pads. Therefore,
drive for a few minutes after cleaning. By
heating up the brakes, the brake discs and
pads dry. The vehicle can then be parked for a
long period of time.
Cleaning the windows
G WARNING
You could become trapped by the windshield
wipers if they start moving while cleaning the
windshield or wiper blades. There is a risk of
injury.
Always switch off the windshield wipers and
the ignition before cleaning the windshield or
wiper blades.
! Only fold the windshield wipers away from
the windshield when vertical. Otherwise, you
will damage the hood.
! Do not use dry cloths, abrasive products,
solvents or cleaning agents containing sol-
vents to clean the inside of the windows. Do
not touch the insides of the windows with
hard objects, e.g. an ice scraper or ring. There
is otherwise a risk of damaging the windows. Care 261
Maintenance and care Z

! Clean the water drainage channels of the
windshield and the rear window at regular
intervals. Deposits such as leaves, petals and
pollen may under certain circumstances pre-
vent water from draining away. This can lead
to corrosion damage and damage to elec-
tronic components. X
Clean the inside and outside of the windows
with a damp cloth and a cleaning product that
is recommended and approved by Mercedes-
Benz.
Cleaning wiper blades
G WARNING
You could become trapped by the windshield
wipers if they start moving while cleaning the
windshield or wiper blades. There is a risk of
injury.
Always switch off the windshield wipers and
the ignition before cleaning the windshield or
wiper blades.
! Only fold the windshield wipers away from
the windshield when vertical. Otherwise, you
will damage the hood.
! Do not pull the wiper blade. Otherwise, the
wiper blade could be damaged.
! Do not clean wiper blades too often and do
not rub them too hard. Otherwise, the graph-
ite coating could be damaged. This could
cause wiper noise.
! Hold the wiper arm securely when folding
back. The windshield could be damaged if the
wiper arm smacks against it suddenly. X
Fold the windshield wiper arms away from the
windshield. X
Carefully clean the wiper blades with a damp
cloth. X
Fold the windshield wiper arms back again
before switching on the ignition.
Cleaning the exterior lighting
! Only use cleaning agents or cleaning cloths
which are suitable for plastic light lenses.
Unsuitable cleaning agents or cleaning cloths
could scratch or damage the plastic light len-
ses. X
Clean the plastic lenses of the exterior lights
with a wet sponge and a mild cleaning agent,
e.g. Mercedes-Benz car shampoo or cleaning
cloths.
Cleaning the mirror turn signals
! Only use cleaning agents or cleaning cloths
that are suitable for plastic lenses. Unsuitable
cleaning agents or cleaning cloths could
scratch or damage the plastic lenses of the
mirror turn signals. X
Clean the plastic lenses of the mirror turn sig-
nals in the exterior mirror housing using a wet
sponge and mild cleaning agent, e.g.
Mercedes-Benz car shampoo or cleaning
cloths.
Cleaning the sensors
! If you clean the sensors with a power
washer, make sure that you keep a distance
of at least 11.8 in (30 cm) between the vehicle
and the power washer nozzle. Information
about the correct distance is available from
the equipment manufacturer.
X
Clean sensors C of the driving systems with
water, car shampoo and a soft cloth.
Cleaning the rear view camera
! Do not clean the camera lens and the area
around the rear view camera with a power
washer.262
Care
Maintenance and care

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

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

i Jumper cables and further information regarding jump-starting can be obtained at any qualified
specialist workshop.
Towing and tow-starting
Important safety notes
G WARNING
Functions relevant to safety are restricted or
no longer available if: R
the engine is not running. R
the brake system or the power steering is
malfunctioning. R
there is a malfunction in the voltage supply
or the vehicle's electrical system.
If your vehicle is being towed, much more
force may be necessary to steer or brake.
There is a risk of an accident.
In such cases, use a tow bar. Before towing,
make sure that the steering moves freely.
G WARNING
You can no longer steer the vehicle if the
steering wheel lock has been engaged. There
is a risk of an accident.
Always switch off the ignition when towing the
vehicle with a tow cable or a tow bar.
G WARNING
When towing or tow-starting another vehicle
and its weight is greater than the permissible
gross weight of your vehicle, the: R
the towing eye could detach itself R
the vehicle/trailer combination could roll-
over.
There is a risk of an accident.
When towing or tow-starting another vehicle,
its weight should not be greater than the per-
missible gross weight of your vehicle.
Details on the permissible gross vehicle weight
of your vehicle can be found on the vehicle iden-
tification plate ( Y
page 308).
! When Active Brake Assist, Distance Pilot
DISTRONIC or the HOLD function is activated, the vehicle brakes automatically in certain
situations.
To avoid damage to the vehicle, deactivate
these systems in the following or similar sit-
uations: R
when towing the vehicle R
in the car wash
! Make sure that the electric parking brake is
released. If the electric parking brake is faulty,
visit a qualified specialist workshop.
! Only secure the tow rope or tow bar at the
towing eyes. Otherwise, the vehicle could be
damaged.
! Do not use the towing eyes for recovery pur-
poses as this could damage the vehicle. If in
doubt, recover the vehicle with a crane.
! When towing, pull away slowly and
smoothly. If the tractive power is too high, the
vehicles could be damaged.
! The vehicle can be towed a maximum of
30 miles (50km). The towing speed of 30 mph
(50km/h) must not be exceeded.
If the vehicle has to be towed more than
30 miles (50km), the front axle must be raised
or the entire vehicle raised and transported.
! Do not tow with sling-type equipment. This
could damage the vehicle.
! When towing vehicles with KEYLESS-GO,
use the key instead of the Start/Stop button.
Otherwise, the automatic transmission may
shift to position P when the driver's or front-
passenger door are opened, which could lead
to damage to the transmission.
! Vehicles with automatic transmission must
not be started by tow-starting. This could oth-
erwise damage the transmission.
It is better to have the vehicle transported than
to have it towed away.
If the vehicle can no longer be driven because of
an accident or breakdown, you have the follow-
ing options: R
transporting the vehicle276
Towing and tow-starting
Breakdown assistance

As a rule, you should have the vehicle trans-
ported. R
towing the vehicle with a tow rope or tow bar
Only tow the vehicle in exceptional cases.
The battery must be connected and charged.
Otherwise, you: R
cannot turn the SmartKey to position 2 in the
ignition lock R
cannot release the electric parking brake R
cannot move the transmission to position N
The function of the electric parking brake and
the parking lock is dependent on the on-board
voltage.
If the on-board voltage is low or if there is a sys-
tem malfunction: R
the electric parking brake may not be applied
in certain circumstances, or R
the transmission may not be shifted to P
Switch off non-essential consumers, e.g. the
radio.
Disarm the automatic locking feature before the
vehicle is towed ( Y
page 184). You could other-
wise be locked out when pushing or towing the
vehicle.
Installing/removing the towing eye
Installing the towing eye
The brackets for the screw-in towing eye are
located in the bumpers. They are at the rear and
at the front, under covers C . X
Remove the towing eye from the stowage
space.
The towing eye is located with the vehicle tool
kit under the cargo compartment floor
( Y
page 266).
Vehicles with the TIREFIT kit: the towing eye is
beneath the tire inflation compressor. X
Press the mark on cover C inwards in the
direction of the arrow. X
Take cover C off the opening. X
Screw in the towing eye clockwise to the stop.
Removing the towing eye X
Unscrew and remove the towing eye. X
Attach cover C to the bumper and press until
it engages. X
Place the towing eye in the stowage well
beneath the cargo compartment floor in the
cargo compartment ( Y
page 266).X
Vehicles with the TIREFIT kit: put back the tire
inflation compressor.
Towing the vehicle with the front axle
raised Observe the important safety notes when tow-
ing your vehicle with the front axle raised
( Y
page 276).
Only vehicles without 4MATIC can be towed
with the front axle raised.
! Vehicles with 4MATIC must not be towed
with either the front or the rear axle raised, as
doing so will damage the transmission.
Vehicles with 4MATIC may either be towed away
with both axles on the ground or be loaded up
and transported.
! The ignition must be switched off if the vehi-
cle is being towed with the front axle raised.
Otherwise, ESP ®
may intervene and damage
the brake system. X
On vehicles with KEYLESS-GO or the KEY-
LESS-GO start function: you must use the
SmartKey instead of the Start/Stop button
( Y
page 122). X
Make sure that the vehicle is stationary. X
Turn the SmartKey to position 2 in the ignition
lock.Towing and tow-starting 277
Breakdo wn assis tance Z

X
When the vehicle is stationary, depress the
brake pedal and keep it depressed. X
Shift the automatic transmission to posi-
tion P .X
Release the brake pedal. X
Release the electric parking brake. X
Switch off the automatic locking
( Y
page 184).X
Switch on the hazard warning lamps
( Y
page 101).X
Turn the SmartKey in the ignition lock to posi-
tion 0 and leave the SmartKey in the ignition
lock.
Towing a vehicle with both axles on
the ground It is important that you observe the safety
instructions when towing away your vehicle
( Y
page 276). X
On vehicles with KEYLESS-GO or the KEY-
LESS-GO start function: you must use the
SmartKey instead of the Start/Stop button
( Y
page 122).
The automatic transmission automatically shifts
to position P when you open the driver's or front-
passenger door or when you remove the Smart-
Key from the ignition lock. In order to ensure
that the automatic transmission stays in posi-
tion N when towing the vehicle, you must
observe the following points: X
Make sure that the vehicle is stationary. X
Turn the SmartKey to position 2 in the ignition
lock. X
Depress and hold the brake pedal. X
Shift the automatic transmission to position
N . X
Leave the SmartKey in position 2 in the igni-
tion lock. X
Release the brake pedal. X
Release the electric parking brake. X
Switch on the hazard warning lamps
( Y
page 101).
i In order to signal a change of direction when
towing the vehicle with the hazard warning
lamps switched on, use the combination
switch as usual. In this case, only the indicator
lamps for the direction of travel flash. After resetting the combination switch, the hazard
warning lamp starts flashing again.
Transporting the vehicle
4MATIC vehicles or vehicles with auto-
matic transmission
! When the vehicle is loaded for transport, the
front and rear axles must be stationary and on
the same transportation vehicle. Positioning
over the connection point of the transport
vehicle is not permitted. The drive train may
otherwise be damaged.
All vehicles
! You may only secure the vehicle by the
wheels, not by parts of the vehicle such as
axle or steering components. Otherwise, the
vehicle could be damaged. X
Turn the SmartKey to position 2 in the ignition
lock ( Y
page 121). X
Shift the transmission to position N .
As soon as the vehicle has been loaded: X
Prevent the vehicle from rolling away 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
Secure the vehicle.
The towing eye can be used to pull the vehicle
onto a trailer or transporter for transporting pur-
poses.278
Towing and tow-starting
Breakdown assistance