2017 MERCEDES-BENZ CLA-Class ECU

Notes on 4MATIC vehicles
!
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 only either be towed
away with both axles on the ground or be loaded
up and transported.
If the vehicle's transmission, front, or rear axle is
damaged, have the vehicle transported on a
truck or trailer.
In the event of damage to the electrical sys- tem:
If the battery is defective, the automatic trans-
mission will be locked in position P. To shift the
automatic transmission to position N, you must
provide power to the vehicle's electrical system
in the same way as when jump-starting
(
Ypage 273).
Have the vehicle transported on a transporter or
trailer.
Tow-starting (emergency engine
starting)
!
Vehicles with automatic transmission must
not be tow-started. You could otherwise dam-
age the automatic transmission.
iYou can find information on "Jump-starting"
under (Ypage 273).
Fuses
Important safety notes
GWARNING
If you manipulate or bridge a faulty fuse or if
you replace it with a fuse with a higher amper- age, the electric cables could be overloaded.
This could result in a fire. There is a risk of an
accident and injury.
Always replace faulty fuses with the specified
new fuses having the correct amperage.
!Only use fuses that have been approved for
Mercedes-Benz vehicles and which have the
correct fuse rating for the system concerned.
Only use fuses marked with an "S". Other- wise, components or systems could be dam-
aged.
!Make sure that no moisture can enter the
fuse box when the cover is open.
!When closing the cover, make sure that it is
lying correctly on the fuse box. Moisture seep-
ing in or dirt could otherwise impair the oper-
ation of the fuses.
The fuses in your vehicle serve to close down
faulty circuits. If a fuse blows, all the compo-
nents on the circuit and their functions stop
operating.
Blown fuses must be replaced with fuses of the same rating, which you can recognize by the
color and value. The fuse ratings are listed in the
fuse al loca
tion chart.
The fuse allocation chart is in the fuse box in the
front-passenger footwell (
Ypage 280).
If a newly inserted fuse also blows, have the
cause traced and rectified at a qualified special-
ist workshop, e.g. an authorized Mercedes-Benz
Center.
Before changing a fuse
XSecure the vehicle against rolling away
(Ypage 140).
XSwitch off all electrical consumers.
XVehicles without KEYLESS-GO: remove the
SmartKey from the ignition lock.
XVehicles with KEYLESS-GO start-function
or KEYLESS-GO: open the driver's door.
The vehicle electronics now have status 0.
This is the same as the SmartKey having been
removed.
The fuses are located in various fuse boxes:
RFuse box in the engine compartment on the
left-hand side of the vehicle, when viewed in
the direction of travel
RFuse box in the front-passenger footwell
The fuse allocation chart is on the fuse box in the
front-passenger footwell (
Ypage 280).
Fuses279
Breakdown assistance
Z

Important safety notes
GWARNING
If wheels and tires of th ewrong siz eare used,
th ewhee lbrakes or suspension component s
may be damaged. Ther eis aris kof an acci-
dent.
Always replace wheels and tires wit hthose
that fulfill th especification sof th eoriginal
part .
When replacing wheels, mak esur eto use th e
correct:
Rdesignation
Rmodel
When replacing tires ,mak esur eto use th e
correct:
Rdesignation
Rmanufacturer
Rmodel
GWARNIN G
A flat tire severely impairs th edriving ,steer -
ing and braking characteristics of th evehicle.
Ther eis aris kof accident.
Tires without run-flat characteristics :
Rdo notdriv ewit h a flat tire.
Rimmediately replace th eflat tire wit hyour
emergenc yspar ewhee lor spar ewheel, or
consult aqualified specialist workshop.
Tires wit hrun-flat characteristics :
Rpay attention to theinformation and warn -
ing notice son MOExtended tires (tire swit h
run-flat characteristics).
Accessories that are no tapprove dfor your vehi-
cle by Mercedes-Ben zor are no tbein gused cor-
rectl ycan impair th eoperating safety.
Before purchasing and usin gnon-approve d
accessories, visit aqualified specialist work-
sho pand inquire about :
Rsuitability
Rlegal stipulation s
Rfactory recommendation sFurther information regarding wheels and tires
can be foun
dunder "Wheel/tire combinations"
(
Ypage 306).
You can ask for information regarding permitte d
wheel-tire combination sat an authorize d
Mercedes-Ben zCenter.
Information on tire pressur ecan be found:
Ron th eTir eand Loading Information placard
on th eB-pillar on th edriver' sside
(
Ypage 292)
Rin th etire pressur etable in th efuel filler flap
(Ypage 138)
Runder "Tir epressure" (Ypage 285)
Operation
Information on driving
Checkth etire pressur ewhen th evehicl eis
heavily laden and adjust prio rto atrip.
While driving ,pay attention to vibrations, noises
and unusual handlin gcharacteristics ,e.g. pull-
ing to on eside .This may indicat ethat th e
wheels or tires are damaged. If you suspec tthat
a tire is defective, reduce your spee dimmedi-
ately. Stop th evehicl eas soo nas possible to
chec kth ewheels and tires for damage. Hidden
tire damag ecould also be causing th eunusual
handlin gcharacteristics .If you fin dno sign sof
damage, hav eth etires and wheels checke dat a
qualified specialist workshop.
When parking your vehicle, mak esur ethat th e
tires do no tget deformed by th ecur bor other
obstacles. If they canno tbe avoided, driv eove r
obstacles suc has curbs slowly and at an obtuse
angle. Otherwise, you may damag eth ewheels
or tires .
Regular checking of wheels and tires
GWARNIN G
Damaged tires can caus etire inflation pres-
sur eloss .As aresult ,you could lose control of
your vehicle. Ther eis aris kof accident.
Chec kth etires regularly for sign sof damag e
and replace any damaged tires immediately.
282Operation
Wheels and tires

Overinflated tires may:
Rincrease the braking distance
Radversely affect handling
Rwear excessively and/or unevenly
Rhave an adverse effect on ride comfort
Rbe more susceptible to damage
Maximum tire pressures
:Example: maximum permissible tire pres-
sure
Never exceed the maximum permissible tire
inflation pressure. Always observe the recom-
mended tire pressure for your vehicle when
adjusting the tire pressure (
Ypage 285).
iThe actual values for tires are vehicle-spe-
cific and may deviate from the values in the
illustration.
Checking the tire pressures
Important safety notes
Observe the notes on tire pressure
(Ypage 285).
Information on air pressure for the tires on your
vehicle can be found:
Ron the vehicle's Tire and Loading Information
placard on the B-pillar
Rin the tire pressure table in the fuel filler flap
(Ypage 138)
Rin the "Tire pressure" section
Checking tire pressures manually
To determine and set the correct tire pressure,
proceed as follows:
XRemove the valve cap of the tire that is to be
checked.
XPress the tire pressure gauge securely onto
the valve.
XRead the tire pressure and compare it to the
recommended value on the Tire and Loading
Information placard or the tire pressure table (
Ypage 285).
XIf the tire pressure is too low, increase the tire
pressure to the recommended value.
XIf the tire pressure is too high, release air. To
do so, press down the metal pin in the valve,
using the tip of a pen for example. Then check
the tire pressure again using the tire pressure
checker.
XScrew the valve cap onto the valve.
XRepeat these steps for the other tires.
Tire pressure loss warning system
(Canada only)
General notes
While the vehicle is in motion, the tire pressure
loss warning system monitors the set tire pres-
sure using the rotational speed of the wheels.
This enables the system to detect significant
pressure loss in a tire. If the speed of rotation of
a wheel changes as a result of a loss of pressure,
a corresponding warning message will appear in
the multifunction display.
You can recognize the tire pressure loss warning
by the Run Flat Indicator Active Press
'OK'toRestartmessage in the multifunction
display in the Serv.menu. Information on the
message display can be found in the "Restarting
the tire pressure loss warning system" section
(
Ypage 289).
Important safety notes
The tire pressure warning system does not warn
you of an incorrectly set tire pressure. Observe
the notes on the recommended tire pressure
(
Ypage 285).
The tire pressure loss warning does not replace
the need to regularly check the tire pressure. An
even loss of pressure on several tires at the
288Tire pressure
Wheels and tires

Important safety notes
GWARNING
Eac htire, includin gth espar e(if provided),
should be checke dat least once every two
week swhen cold and inflated to th epressur e
recommended by th evehicl emanufacturer
on th eTir eand Loading Information placard
on th edriver' sdoor B-pillar or th etire pres-
sur elabel on th einside of th efuel filler flap .If
your vehicl ehas tires of adifferen tsiz ethan
th esiz eindicated on th eTir eand Loading
Information placard or, if available, th etire
pressur elabel, you should determine th e
proper tire pressur efor those tires .
As an added safet yfeature, your vehicl ehas
been equipped wit h atire pressur emonitoring
system (TPMS) that illuminate s alow tire pres-
sur etelltale when on eor mor eof your tires
are significantly underinflated. Accordingly,
when th elow tire pressur etelltale lights up,
you should stop and chec kyour tires as soo n
as possible ,and inflat ethem to th eproper
pressure. Drivin gon asignificantly underin-
flated tire causes th etire to overheat and can
lead to tire failure.
Underinflation also reduce sfuel efficiency
and tire tread life ,and may affec tth evehicle's
handlin gand stopping ability. Pleas enote that
th eTPM Sis no t asubstitut efor proper tire
mainte nance,a
nd it is th edriver' sresponsi-
bilit yto maintai ncorrec ttire pressure, eve nif
underinflation has no treached th elevel to
trigge rillumination of th eTPM Slow tire pres-
sur etelltale.
Your vehicl ehas also been equipped wit h a
TPM Smalfunction indicator to indicat ewhen
th esystem is no toperating properly. The
TPM Smalfunction indicator is combined wit h
th elow tire pressur etelltale. When th esys-
te m detects amalfunction ,th ewarning lamp
will flas hfor approximately aminute and then
remain continuously illuminated. This
sequenc ewill be repeated every time th evehi-
cle is started as lon gas th emalfunction
exists. When th emalfunction indicator is illu-
minated, th esystem may no tbe able to detec t
or signal low tire pressur eas intended.
TPM Smalfunction smay occur for avariet yof
reasons, includin gth einstallation of incom-
patible replacemen tor alternate tires or
wheels on th evehicl ethat preven tth eTPM S
from functioning properly. Always chec kth e
TPM Smalfunction telltale after replacing on e
or mor etires or wheels on your vehicl eto
ensur ethat th ereplacemen tor alternate Tires
and wheels allow th eTPM Sto continue to
function properly.
It is th edriver' sresponsibilit yto set th etire
pressur eto that recommended for cold tires
whic his suitable for th eoperating situation
(
Ypage 285). Not ethat th ecorrec ttire pressur e
for th ecurren toperating situation must first be
taught-in to th etire pressur emonitor. If asub-
stantial loss of pressur eoccurs, th ewarning
threshold for th ewarning message is aligned to
th etaught-in referenc evalues. Restart th etire
pressur emonitor after adjusting th epressur eof
th ecold tires (
Ypage 291). The curren tpres-
sures are saved as ne wreferenc evalues. As a
result , awarning message will appear if th etire
pressur edrops significantly.
The tire pressur emonit or d
oes no
twarn you of
an incorrectl yset tire pressure. Observ eth e
note son th erecommended tire pressur e
(
Ypage 285).
The tire pressur emonitor is no table to warn you
of asudde nloss of pressure, e.g. if th etire is
penetrated by aforeign object. In th eevent of a
sudde nloss of pressure, brin gth evehicl eto a
halt by braking carefully. Avoid abrup tsteering
movements.
The tire pressur emonitor has ayellow warning
lamp in th einstrumen tcluste rfor indicating
pressur eloss or amalfunction .Whether th e
warning lamp flashes or lights up indicates
whether atire pressur eis to olow or th etire
pressur emonitor is malfunctioning :
Rif thewarning lamp is lit continuously, th etire
pressur eon on eor mor etires is significantly
to olow. The tire pressur emonitor is no tmal-
functioning .
Rif thewarning lamp flashes for aroun d a
minute and then remain slit constantly, th e
tire pressur emonitor is malfunctioning .
In addition to th ewarning lamp , amessage
appear sin th emultifunction display. Observ e
290Tire pressure
Wheels and tires

PSI (pounds per square inch)
A standard 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:
Rif the vehicle has been parked with the tires
out of direct sunlight for at least three hours
and
Rif the vehicle has not been driven further than
1 mile (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 fromthe 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, a roof rack or a high-per-
formance battery, are not included in the curb
weight and the weight of the accessories.
TIN (Tire Identification Number)
This is a unique identifier which can be used by
a tire manufacturer to identify tires, for example
for a product 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 a code
that contains the maximum load bearing capa-
city of a tire.
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 áin (1.6 mm)
has been reached.
Occupant distribution
The distribution of occupants in a vehicle at their
designated seating positions.
Total load limit
Nominal load and luggage load plus 68 kg
(150 lbs) multiplied by the number of seats in
the vehicle.
Changing a wheel
Flat tire
The "Breakdown assistance" section
(Ypage 266) contains information and notes on
how to deal with a flat tire. Information on driv-
ing with MOExtended tires in the event of a flat
tire can be found under "MOExtended tires (tires
with run-flat characteristics" (
Ypage 267).
Rotating the wheels
GWARNING
Interchanging the front and rear wheels may
severely impair the driving characteristics if
the wheels or tires have different dimensions. The wheel brakes or suspension components
may also be damaged. There is a risk of acci-
dent.
Rotate front and rear wheels only if the wheels and tires are of the same dimensions.
!On vehicles equipped with a tire pressure
monitor, electronic components are located
in the wheel.
Changing a wheel301
Wheels and tires
Z

Tire-mounting tools should not be used near
the valve. This could damage the electronic
components.
Only have tires changed at a qualified spe-
cialist workshop.
Observe the instructions and safety notes in the
"Changing a wheel" section (
Ypage 301).
The wear patterns on the front and rear tires
differ, depending on the operating conditions.
Rotate the wheels before a clear wear pattern
has formed on the tires. Front tires typically
wear more on the shoulders and the rear tires in
the center.
On vehicles that have the same size front and
rear wheels, you can rotate the wheels accord-
ing to the intervals in the tire manufacturer's
warranty book in your vehicle documents. If no
warranty book is available, the tires should be
rotated every 3,000 to 6,000 miles (5,000 to
10,000 km). Depending on tire wear, this may
be required earlier. Do not change the direction
of wheel rotation.
Clean the contact surfaces of the wheel and the brake disc thoroughly every time a wheel is rota-
ted. Check the tire pressure and, if necessary,
restart the tire pressure loss warning system
(Canada only) or the tire pressure monitor (USA
only).
Direction of rotation
Tires with a specified direction of rotation have
additional benefits, e.g. if there is a risk of hydro-
planing. These advantages can only be gained if
the tires are installed corresponding to the
direction of rotation.
An arrow on the sidewall of the tire indicates its
correct direction of rotation.
Storing wheels
Store wheels that are not being used in a cool,
dry and preferably dark place. Protect the tires
from oil, grease, gasoline and diesel.
Mounting a wheel
Preparing the vehicle
XStop the vehicle on solid, non-slippery and
level ground.
XApply the electric parking brake manually.
XBring the front wheels into the straight-ahead position.
XShift the transmission to position P.
XSwitch off the engine.
XVehicles without KEYLESS-GO:remove the
SmartKey from the ignition lock.
XVehicles with KEYLESS-GO start-function
or KEYLESS-GO: open the driver's door.
The vehicle electronics now have status 0.
This is the same as the SmartKey having been
removed.
XVehicles with KEYLESS-GO start-function
or KEYLESS-GO: remove the Start/Stop but-
ton from the ignition lock (
Ypage 121).
XMake sure that the engine cannot be started
via your smartphone (Ypage 122).
XIf included in the vehicle equipment, remove
the tire-change tool kit from the vehicle.
XSafeguard the vehicle against rolling away
(Ypage 140).
Securing the vehicle to prevent it from
rolling away
If your vehicle is equipped with a wheel chock, it
can be found in the tire-change tool kit
(
Ypage 266).
The folding wheel chock is an additional safety
measure to prevent the vehicle from rolling
away, for example when changing a wheel.
302Changing a wheel
Wheels and tires

XFold both plates upwards:.
XFold out lower plate;.
XGuide the lugs on the lower plate fully into the
openings in base plate =.
XPlace chocks or other suitable items under
the front and rear of the wheel that is diago-
nally opposite the wheel you wish to change.
Raising the vehicle
GWARNING
If you do not position the jack correctly at the
appropriate jacking point of the vehicle, the
jack could tip over with the vehicle raised.
There is a risk of injury.
Only position the jack at the appropriate jack-
ing point of the vehicle. The base of the jack
must be positioned vertically, directly under
the jacking point of the vehicle.
!The jack is designed exclusively for jacking
up the vehicle at the jacking points. Other-
wise, your vehicle could be damaged.
Observe the following when raising the vehi-
cle:
RTo raise the vehicle, only use the vehicle-spe-
cific jack that has been tested and approved
by Mercedes-Benz. If used incorrectly, the
jack could tip over with the vehicle raised.
RThe jack is designed only to raise and hold the
vehicle for a short time while a wheel is being
changed. It must not be used for performing
maintenance work under the vehicle.
RAvoid changing the wheel on uphill and down- hill slopes.
RBefore raising the vehicle, secure it from roll-
ing away by applying the parking brake and inserting wheel chocks. Do not disengage the
parking brake while the vehicle is raised.
RThe jack must be placed on a firm, flat and
non-slip surface. On a loose surface, a large,
flat, load-bearing underlay must be used. On a
slippery surface, a non-slip underlay must be
used, e.g. rubber mats.
RDo not use wooden blocks or similar objects
as
a jack underlay. Otherwise, the jack will not
be able to achieve its load-bearing capacity
due to the restricted height.
RMake sure that the distance between the
underside of the tires and the ground does not
exceed 1.2 in (3 cm).
RNever place your hands and feet under the
raised vehicle.
RDo not lie under the vehicle.
RDo not start the engine when the vehicle is
raised.
RDo not open or close a door or the trunk lid
when the vehicle is raised.
RMake sure that no persons are present in the
vehicle when the vehicle is raised.
XUsing lug wrench :, loosen the bolts on the
wheel you wish to change by about one full
turn. Do not unscrew the bolts completely.
Jacking points
Changing a wheel303
Wheels and tires
Z

Always pay attention to the instructions and
safety notes in the "Changing a wheel" section
(
Ypage 301).
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 prevent damage to the paintwork, hold
the wheel securely against the wheel hub
while screwing in the first wheel bolt.
XClean the wheel and wheel hub contact sur-
faces.
XPlace the new wheel on the wheel hub and
push it on.
XTighten the wheel bolts until they are finger-
tight.
Lowering the vehicle
GWARNING
The wheels could work loose if the wheel nuts and bolts are not tightened to the specified
tightening torque. There is a risk of accident.
Have the tightening torque immediately
checked at a qualified specialist workshop
after a wheel is changed.
XPlace the ratchet wrench onto the hexagon
nut of the jack so that the letters ABare visi-
ble.
XTurn the ratchet wrench until the vehicle is
once again standing firmly on the ground.
XPlace the jack to one side.
XTighten the wheel bolts evenly in a crosswise pattern in the sequence indicated ( :toA).
The specified tightening torque is 96 lb-ft
(130 Nm) .
XTurn the jack back to its initial position.
XStow the jack and the rest of the vehicle tools
in the vehicle again.
XMercedes-AMG vehicles and vehicles
with AMG equipment: insert the cover into
the outer sill.
XCheck the tire pressure of the newly mounted
wheel and adjust it if necessary.
Observe the recommended tire pressure
(
Ypage 285).
Canada only: as long as you are driving with the
emergency spare wheel mounted, the tire pres- sure loss warning system cannot function relia-
bly. Only restart the tire pressure loss warning
system when the defective wheel has been
replaced with a new wheel.
Vehicles with tire pressure monitor (USA
only): all mounted wheels must be equipped
with functioning sensors.
Changing a wheel305
Wheels and tires
Z