ECU MERCEDES-BENZ CLA 2018 Workshop Manual

Cleaning wiper blades
G WARNING
You coul db ecome trapped by th ew indshield
wiper sift he ys ta rt moving while cleanin gt he
windshield or wiper blades .T her eisar is ko f
injury.
Always switch off th ew indshield wiper sa nd
th ei gnition before cleanin gt he windshield or
wiper blades.
! Only fold th ew indshield wiper sa way from
th ew indshield when vertical. Otherwise, you
will damag et he hood.
! Do no tp ull th ew iper blade. Otherwise, the
wiper blade coul dbed amaged.
! Do no tc lean wiper blades to oo ften and do
no tr ub them to oh ard .O th erwise, th eg raph-
ite coatin gc oul dbed amaged. This could
caus ew iper noise.
! Hol dt he wiper arm securely when folding
back .T he windshield coul dbed amaged if the
wiper arm smacks against it suddenly. X
Fol dt he windshield wiper arm sa way from the
windshield. X
Carefully clean th ew iper blades wit had amp
cloth. X
Fol dt he windshield wiper arm sb ack again
before switching on th ei gnition.
Cleaning th ee xterior lighting
! Only use cleanin ga gents or cleanin gc loths
whic ha re suitable for plastic light lenses.
Unsuitable cleanin ga gents or cleanin gc loths
coul ds cr atch or damag et he plastic light len-
ses. X
Clean th ep lastic lenses of th ee xteri or lights
wit haw et sponge and am ild cleanin ga gent,
e.g .M ercedes-Ben zc ar shampoo or cleaning
cloths.
Cleaning th em irror turn signals
! Only use cleanin ga gents or cleanin gc loths
that are suitable for plastic lenses .U ns uitable
cleanin ga gents or cleanin gc loth sc ould
scratch or damag et he plastic lenses of the
mirror tur ns ignals. X
Clean th ep lastic lenses of th em irror tur ns ig-
nals in th ee xteri or mirror housing usin gaw et
sponge and mild cleanin ga gent, e.g.
Mercedes-Ben zc ar shampoo or cleaning
cloths.
Cleaning th es ensors
! If you clean th es ensor sw it hap ower
washer, mak es ure that you keep ad istance
of at least 11.8 in (30 cm )b etween the vehicl e
and th ep ower washer nozzle. Information
about th ec orrec td istanc eisa vailabl ef ro m
th ee quipment manufacturer.
X
Clean sensors C of th ed riving systems with
water, car shampoo and as of tc loth.
Cleaning th er ea rv iew camera
! Do no tc lean th ec amera len sa nd th ea rea
aroun dt he rear view camera with ap ower
washer. Care 265
Maintenance and care Z

the househol dr ubbish .T hey
must be collected separately
and recycle dtop rotect the
environment.
Dispose of batteries in an
environmentall yf riendly
manner. Take discharged
batteries to aq uali fied spe-
cialist workshop or as pe cial
collectio np oi nt for used bat-
teries.
! Hav et he battery checked regularly at a
qualified specialis tw or kshop.
Observe the service intervals in the Mainte-
nanc eB ookle torc ontact aq uali fied specialist
workshop for mor ei nformation.
! Yo us houl dh av ea ll work involvin gt he bat-
tery carrie do ut at aq uali fied specialis tw or k-
shop. In the exceptiona lc as et ha titi sn eces-
sary for yo utod is connect the battery your-
self, make sure that: R
yo us wi tch off the engine and remove the
key .Onv ehicles with KEYLESS-GO, ensure
tha tt he ignition is switched off .C he ck that
al lt he indicator lamps in the instrument
cluste ra re off .O therwise, electronic com-
ponents ,s uc hast he alternator, ma yb e
damaged. R
yo uf irst remove the negative terminal
clamp and the nt he positive terminal
clamp. Never swap the termina lc lamps.
Otherwise, the vehicle' se le ctronic system
ma ybed amaged .R
in vehicles with automatic transmission,
the transmission is locked in position P
after disconnecting the battery .T he vehicle
is secur ed a gainst rolling away .Y ou ca
n
the nnol on ge rm ov et he vehicle.
The battery and the cove roft he positive ter-
minal clamp must be installe ds ec urel yd ur ing
operation.
Compl yw it hs af ety precautions and take pro-
tective measures when handling batteries. Risk of explosion.
Fire, open flames and smoking are
prohibited when handling the bat-
tery .A voi dc reating sparks.
Battery aci disc austic. Avoi dc ontact
with skin, eyes or clothing.
Wear suitabl ep rotective clothing,
especiall yg lo ves, apron and face-
guard.
Rinse any aci ds pills immediately
with clear water. Contact ap hysician
if necessary.
Wear ey ep rotection.
Kee pc hildren away.
Observe thi sO pe rator' sM an ual.
For safety reasons, Mercedes-Benz recom-
mend st ha ty ou onl yu se batteries which have
been tested and approved for your vehicl eb y
Mercedes-Benz. Thes eb at teries provide
increase di mpact protection to prevent vehicle
occupants fro ms uf ferin ga ci db ur ns shoul dt he
battery be damage dint he event of an accident.
In order for the battery to achieve the maximum
possibl es er vice life, it must always be suffi-
ciently charged.
Like othe rb at teries ,t he vehicl eb at tery may
discharge ove rt im eify ou do not us et he vehicle.
In thi sc ase, have the battery disconnecte data
qualified specialis tw or kshop .Y ou can also
charge the battery with ac harge rr ecommended
by Mercedes-Benz. Contact aq uali fied special-
is tw or kshop for furthe ri nformation.
Hav et he battery condition of charge checked
mor ef requentl yify ou us et he vehicl em ai nl yf or
short trip sorify ou leav eits tanding idle for a
length yp er iod. Consult aq uali fied specialist
workshop if yo uw is htol eave your vehicle
parked for al on gp er io doft ime.
Onl yr eplace ab at tery with ab at tery tha th as
been recommended by Mercedes-Benz.Battery (vehicle) 277
Breakdow na ssistance Z

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 pulle yort he fan.X
Secure the vehicle by applying the electric parking brake. X
Shift the transmission to position ] .X
Turn the SmartKey to position Z 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 cable sa nd further informatio nr egardin gj ump-startin gc an be obtaine data ny qualified
specialist workshop.
Towing and tow-starting
Important safety notes
G WARNING
Function sr elevan ttos afety are restricted or
no longer available if: R
th ee ngine is no tr unning.R
th eb rak es ystem or th ep ower steering is
malfunctioning. R
there is am alfunctio nint he voltage supply
or th ev ehicle's electrical system.
If your vehicle is bein gt ow ed, muc hm ore
force may be necessar yt os te er or brake.
Ther eisar isk of an accident.
In such cases, use at ow bar. Before towing,
mak es ure that th es te ering moves freely.
G WARNING
You can no longer steer th ev ehicle if the
steering wheel loc kh as been engaged. There
is ar isk of an accident.
Always switch off th ei gnitio nw hen towing the
vehicle with at ow cable or at ow bar.
G WARNING
When towing or tow-startin ga nother vehicle
and its weight is greater than th ep ermissible
gross weight of your vehicle ,t he :R
th et ow ing eye could detach itselfR
th ev ehicle/trailer combinatio nc ould roll-
over.
Ther eisar isk of an accident.
When towing or tow-startin ga nother vehicle,
its weight shoul dn ot be greater than th ep er-
missible gross weight of your vehicle.
Details on th ep ermissible gross vehicle weight
of your vehicle can be foun dont he vehicle iden-
tification plat e( Y
page 314).
! When Activ eB ra ke Assist ,D istance Pilot
DISTRONIC or th eH OL Df unction is activated, th ev ehicle brakes automatically in certain
situations.
To avoid damage to th ev ehicle ,d eactivate
these systems in th ef ollowing or similar sit-
uations: R
when towing th ev ehicle R
in th ec ar wash
! Mak es ure that th ee lectric parking brak ei s
released. If th ee lectric parking brak eisf aulty,
visi taq ualifie ds pecialist workshop.
! Only secure th et ow rope or to wb ar at the
towing eyes. Otherwise, th ev ehicle coul db e
damaged.
! Do no tu se th et ow ing eyes for recover yp ur-
pose sast hi sc oul dd amage th ev ehicle .Ifi n
doubt ,r ecover th ev ehicle with ac ra ne.
! When towing ,p ull away slowly and
smoothly. If th et ra ctive power is to oh igh ,t he
vehicle sc oul dbed amaged.
! The vehicle can be towed am aximum of
30 miles (50km). The t owing speed of 30 mph
(5 0km/h) must no tbee xceeded.
If th ev ehicle has to be towed mor et ha n
30 miles (50km), th ef ront axle must be raised
or th ee ntire vehicle raise da nd transported.
! Do no tt ow with sling-type equipment .T his
coul dd amage th ev ehicle.
! When towing vehicle sw ith KEYLESS-GO,
use th ek ey instead of th eS ta rt/Sto pb utton.
Otherwise, th ea utomatic transmission may
shif ttop osition P when th ed river' sorf ront -
passenger door are opened, whic hc oul dl ead
to damage to th et ra nsmission.
! Vehicles with automatic transmission must
no tbes ta rted by tow-starting. This coul do th -
erwis ed amage th et ra nsmission.
It is bette rtoh ave th ev ehicle transported than
to have it towed away.
If th ev ehicle can no longer be driven because of
an acciden torb reakdown ,y ou have th ef ollow-
ing options: R
Transportin gt he vehicle.Towing and tow-starting 281
Breakdown assistance Z

X
When the vehicle is stationary, depress the
brake pedal and keep it depressed. X
Shift the automatic transmission to position
] . X
Release the brake pedal. X
Release the electric parking brake. X
Switc ho ff the automatic locking
( Y
page 187). X
Switc hont he hazard warning lamps
( Y
page 102). X
Turn the SmartKey in the ignition lock to posi-
tion Z and leave the SmartKey in the ignition
lock.
Towing av ehicle with both axles on
the ground It is importan tt hat you observe the safety
instruction sw hen towing away your vehicle
( Y
page 281). X
On vehicles with KEYLESS-GO or the KEY-
LESS-GO star tf unction: you must use the
SmartKey instead of the Start/Stop button
( Y
page 123).
The automatic transmission automatically shifts
to position ] when you open the driver's or
front-passenger door or when you remove the
SmartKey from the ignition lock. In order to
ensure that the automatic transmission stays in
position \\ when towing away the vehicle, you
must observe the following points: X
Make sure that the vehicle is stationary. X
Turn the SmartKey to position H in the igni-
tion lock. X
Depress and hold the brake pedal. X
Shift the automatic transmission to position
\\ . X
Leave the SmartKey in position H in the igni-
tion lock. X
Release the brake pedal. X
Release the electric parking brake. X
Switc hont he hazard warning lamps
( Y
page 102).
i In order to signal ac hange 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 start sf lashing again.
Transporting the vehicle
4MATIC vehicles or vehicles with auto-
matic transmission
! When the vehicle is loaded for transport, the
fron ta nd 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 steerin gc omponents. Otherwise, the
vehicle could be damaged. X
Turn the SmartKey to position H in the igni-
tion lock ( Y
page 122). X
Shift the transmission to position \\ .
As soon as the vehicle has been loaded: X
Preven tt he vehicle from rolling away by
applying the electric parking brake. X
Shift the transmission to position ] .X
Turn the SmartKey to position Z in the igni-
tion lock and remove it. X
Secure the vehicle.
The towing eye can be used to pull the vehicle
ont oat railer or transporter for transportin gp ur-
poses.Towing and tow-starting 283
Breakdown assistance Z

Note son4 MATIC vehicles
! Vehicle sw it h4 MATIC must not be towed
with eithe rt he front or the rea ra xl er aised, as
doing so will damage the transmission.
Vehicle sw it h4 MATIC ma yo nl ye it he rbet owed
away with both axles on the ground or be loaded
up and transported.
If the vehicle' st ransmission, front, or rea ra xl ei s
damaged, have the vehicl et ransporte dona
truck or trailer.
In the even to fd amag etot he electrical sys-
tem:
If the battery is defective, the automatic trans-
mission will be locked in position ] .Tos hift the
automatic transmission to position \\ ,y ou
must provide powe rtot he vehicle' so n-board
electrica ls ys te mint he same wa yasw he nj ump-
starting ( Y
page 278).
Have the vehicl et ransporte donat ransporte ro r
trailer.
Tow-startin g( em ergency engine
starting)
! Vehicle sw it ha ut omatic transmission must
not be tow-started .Y ou could otherwis ed am -
ag et he automatic transmission.
i Yo uc an find information on "Jump-starting"
under ( Y
page 278).
Fuses
Important safety notes
G WARNING
If yo um an ipulate or bridg eaf aulty fuse or if
yo ur eplace it with af us ew it hah ighe ra mper -
age, the electric cable sc ould be overloaded.
This could resul tina fire. There is ar is kofa n
accident and injury.
Alway sr eplace faulty fuse sw it ht he specified
new fuse sh avin gt he correc ta mperage.
! Onl yu se fuse st ha th av eb ee na pp roved for
Mercedes-Benz vehicles and which have the
correc tf us er at ing for the syste mc oncerned.
Onl yu se fuse sm ar ked with an "S" .O ther- wise ,c omponents or systems could be dam-
aged.
! Make sure tha tnom oisture can ente rt he
fuse bo xw he nt he cover is open.
! When closing the cover, make sure tha titi s
lying correctly on the fuse box. Moistur es eep-
ing in or dirt could otherwis ei mpair the oper-
ation of the fuses.
Th ef uses in your vehicl es er ve to close down
faulty circuits .Ifa fuse blows, al lt he compo-
nents on the circuit and their functions stop
operating.
Blown fuse sm us tber eplaced with fuse soft he
same rating ,w hi ch yo uc an recognize by the
color and value. Th ef us er at ing sa re liste dint he
fuse allocation chart.
Th ef us ea lloc at io nc h art is in the fuse bo xi nt he
front-passenge rf ootwell ( Y
page 285).
If an ewly inserte df us ea ls ob lows ,h av et he
cause traced and rectifie dataq ualified special-
is tw or kshop ,e .g .ana ut horized Mercedes-Benz
Center.
Before changin gaf use X
Secure the vehicl ea gain st rolling away
( Y
page 141). X
Switch off al le le ctrica lc onsumers.X
Vehicle sw it hout KEYLESS-GO: remove the
SmartKe yf ro mt he ignition lock. X
Vehicle sw it hK EYLESS -G Os tart-function
or KEYLESS-GO: open the driver's door.
Th ev ehicl ee le ctronics ar en ow in position
Z .T hi sc orresponds to the SmartKe yb ei ng
remove df ro mt he ignition.
Th ef uses ar el oc ated in variou sf us eb ox es:R
Fuse bo xint he engine compartment on the
left-hand side of the vehicle, when viewed in
the directio noft ravel R
Fuse bo xint he front-passenge rf ootwell
Th ef us ea lloc atio nc hart is on the fuse bo xint he
front-passenge rf ootwell ( Y
page 285).284
Fuses
Breakdow na ssistance

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
becaus et he ya re damaged mor ee asily by
road debris ,p otholes etc .Ina ddition, they
also suffer fro mi rregular wear, which can
severely impair th eb raking properties and the
driving characteristics. Ther eisar isk of an
accident.
Avoid tir ep ressures that are too high in all the
tires, including th es pare wheel.
Overinflated tires may: R
increase th eb raking distanceR
adversely affect handling R
wear excessively and/or unevenly R
have an adverse effect on ride comfort R
be mor es usceptible to damage
Maximu mt ir ep re ssures
C
Example: maximum permissible tir ep res-
sure
Never exceed th em aximum permissible tire
inflatio np ressure. Always observe th er ecom-
mended tir ep ressure for your vehicle when
adjustin gt he tir ep ressure ( Y
page 290).
i The actual values for tires are vehicle-spe-
cific and may deviat ef ro mt he values in the
illustration. Checking th et ir ep re ssures
Important safety notes Observe th en otes on tir ep ressure
( Y
page 290).
Information on air pressure for th et ires on your
vehicle can be found: R
on th ev ehicle's Tire and Loadin gI nf ormation
placar dont he B-pillar R
in th et ir ep ressure table in th ef uel filler flap
( Y
page 139) R
in th e" Tire pressure" section
Checking tir ep re ssures manuallyTo determine and set th ec orrec tt ir ep ressure,
proceed as follows: X
Remov et he valve cap of th et ir et ha tistob e
checked. X
Pres st he tir ep ressure gauge securely onto
th ev alve. X
Read th et ir ep ressure and compare it to the
recommended value on th eT ire and Loading
Information placar dort he tir ep ressure table
( Y
page 290). X
If th et ir ep ressure is too low, increase th et ire
pressure to th er ecommended value. X
If th et ir ep ressure is too high, releas ea ir. To
do so, pres sd own th em etal pin in th ev alve,
using th et ip of ap en for example. Then check
th et ir ep ressure again using th et ir ep ressure
checker. X
Screw th ev alve cap ont ot he valve.X
Repeat these steps for th eo ther tires.
Tir ep re ssur el oss warning system
(Canada only)
General notes While th ev ehicle is in motion, th et ir ep ressure
loss warning system monitors th es et tir ep res-
sure using th er otational speed of th ew heels.
This enables th es ystem to detect significant
pressure loss in at ire. If th es peed of rotation of
aw heel changes as ar esult of al oss of pressure,
ac orresponding warning message will appear in
th em ultifunction display.
You can recognize th et ir ep ressure loss warning
by the Run Flat Indicato rA ctive PressTir ep re ssure 293
Wheels and tires Z

PSI (pounds per squar ei nch)As tandard unit of measure for tire pressure.
Aspect ratio Relationship between tire height and tire width
in percent.
Tire pressure This is pressure inside the tire applying an out-
ward force to each square inch of the tire's sur-
face. The tire pressure is specified in pounds per
square inch (psi), in kilopascal (kPa) or in bar.
The tire pressure should only be corrected when
the tires are cold.
Cold tire pressure The tires are cold: R
if the vehicle has been parked with the tires
out of direct sunlight for at least three hours
and R
if the vehicle has not been driven further than
1m ile (1.6 km)
Tread The part of the tire that comes into contact with
the road.
Bead The tire bead ensures that the tire sits securely
on the wheel. There are several steel wires in the
bead to prevent the tire from coming loose from
the wheel rim.
Sidewall The part of the tire between the tread and the
bead.
Weight of optional extras
The combined weight of those optional extras
that weigh more than the replaced standard
parts and more than 2.3 kg (5 lbs). These
optional extras, such as high-performance
brakes, level control, ar oof rack or ah igh-per-
formanc eb attery, are not included in the curb
weight and the weight of the accessories.
TIN (Tire Identification Number)
This is au nique identifier which can be used by
at ire manufacturer to identify tires, for example
for ap roduct recall, and thus identify the pur-
chasers. The TIN is made up of the manufactur-
er's identity code, tire size, tire type code and
the manufacturing date. Load bearing index The load bearing index (also load index) is ac ode
that contains the maximum load bearing capa-
city of at ire.
Traction Traction is the result of friction between the tires
and the road surface.
Treadwear indicators Narrow bars (tread wear bars) that are distrib-
uted over the tire tread. If the tire tread is level
with the bars, the wear limit of

Securing the vehicle to prevent it from
rolling away
If your vehicle is equippe dw ith aw heel chock ,i t
can be found in the tire-change tool kit
( Y
page 270).
The folding wheel chock is an additional safety
measure to prevent the vehicle from rolling
away ,f or example when changing aw heel.X
Fold both plates up C .X
Fold out lower plate D .X
Guide the lugs on the lower plate fully into the
openings in base plate

bolts to come loose. As ar esult, you could
lose aw heel while driving .T here is ar isk of
accident.
Never oil or grease wheel bolts. In the event of
damage to the threads, contact aq ualified
specialist workshop immediately. Have the
damaged wheel bolts or hub threads
replaced/renewed. Do not continue driving.
G WARNING
If you tighten the wheel bolts or wheel nuts
when the vehicle is raised, the jack could tip
over. There is ar isk of injury.
Only tighten the wheel bolts or wheel nuts
when the vehicle is on the ground.
Always pay attention to the instructions and
safety notes in the "Changing aw heel" section
( Y
page 307).
Only use wheel bolts that have been designed
for the wheel and the vehicle. For safety rea-
sons, Mercedes-Benz recommends that you
only use wheel bolts which have been approved
for Mercedes-Benz vehicles and the respective
wheel.
! To preven td amage to the paintwork, hold
the wheel securely against the wheel hub
while screwin gint he first wheel bolt.
X
Clean the wheel and wheel hub contact sur-
faces. X
Place the new wheel on the wheel hub and
push it on. X
Tighten the wheel bolts until they are finger-
tight. Lowering the vehicle
G WARNING
The wheels could work loose if the wheel nuts
and bolts are not tightened to the specified
tightenin gt orque. There is ar isk of accident.
Have the tightenin gt orque immediately
checked at aq ualified specialist workshop
after aw heel is changed. X
Place the ratchet wrenc ho nt ot he hexagon
nut of the jack so that the letters AB are visi-
ble. X
Turn the ratchet wrenc hu ntil the vehicle is
onc ea gain standing firmly on the ground. X
Place the jack to one side.
X
Tighten the wheel bolts evenly in ac rosswise
pattern in the sequence indicated ( C to