ignition MERCEDES-BENZ CLA 2017 Repair Manual

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
( Y
page 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.
i You can find information on "Jump-starting"
under ( Y
page 273).
Fuses
Important safety notes
G WARNING
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.
T he fuse allocation chart is in the fuse box in the
front-passenger footwell ( Y
page 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 X
Secure the vehicle against rolling away
( Y
page 140). X
Switch off all electrical consumers. X
Vehicles without KEYLESS-GO: remove the
SmartKey from the ignition lock. X
Vehicles 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: R
Fuse box in the engine compartment on the
left-hand side of the vehicle, when viewed in
the direction of travel R
Fuse box in the front-passenger footwell
The fuse allocation chart is on the fuse box in the
front-passenger footwell ( Y
page 280).Fuses 279
Breakdown assistance Z

Fuse box in the engine compartment
G WARNIN G
When th e hoo d is open and th e windshield
wiper s are set in motion , you can be injured by
th e wiper linkage. Ther e is a ris k of injury.
Always switch off th e windshield wiper s and
th e ignition before opening th e hood.
X
Open th e hood.X
Use a dry cloth to remove any moisture from
th e fus e box .X
To open : open clamps D .X
Fold up cover C in th e direction of th e arrow
and remove it .
X
To close: check whether th e seal is lyin g cor-
rectl y in cover C .X
Inser t cover C at th e bac k int o opening s

same time cannot be detected by the tire pres-
sure loss warning system.
The tire pressure monitor is not able to warn you
of a sudden loss of pressure, e.g. if the tire is
penetrated by a foreign object. In the event of a
sudden loss of pressure, bring the vehicle to a
halt by braking carefully. Avoid abrupt steering
movements.
The function of the tire pressure loss warning
system is limited or delayed if: R
snow chains are mounted on your vehicle's
tires. R
road conditions are wintry. R
you are driving on sand or gravel. R
you adopt a very sporty driving style (corner-
ing at high speeds or driving with high rates of
acceleration). R
you are driving with a heavy load (in the vehi-
cle or on the roof)
Restarting the tire pressure loss warn-
ing system Restart the tire pressure loss warning system if
you have: R
changed the tire pressure R
changed the wheels or tires R
mounted new wheels or tires X
Before restarting, make sure that the tire
pressures are set properly on all four tires for
the respective operating conditions.
The recommended tire pressure can be found
on the Tire and Loading Information placard
on the B-pillar. Additionally, a tire pressure
table is attached to the fuel filler flap. The tire
pressure loss warning system can only give
reliable warnings if you have set the correct
tire pressure. If an incorrect tire pressure is
set, these incorrect values will be monitored. X
Also observe the notes in the section on tire
pressures ( Y
page 285).X
Make sure that the SmartKey is in position 2
in the ignition lock ( Y
page 121).X
Press Y or e on the steering wheel to
select the Serv. menu.X
Press the c or d button to select
Tire Pressure .X
Press the v button.
The Run Flat Indicator Active Press
'OK' to Restart message appears in the
multifunction display. If you wish to confirm the restart: X
Press the v button.
The Tire Pressure Now OK? message
appears in the multifunction display. X
Press the c or d button to select Yes .X
Press the v button.
The Run Flat Indicator Restarted mes-
sage appears in the multifunction display.
After a teach-in period, the tire pressure loss
warning system will monitor the set tire pres-
sures of all four tires.
If you wish to cancel the restart: X
Press the 8 button.
or X
If the Tire Pressure Now OK? message
appears, press the c or d button to
select Cancel . X
Press the v button.
The tire pressure values stored at the last
restart will continue to be monitored.
Tire pressure monitor
General notes If a tire pressure monitor is installed, the vehi-
cle's wheels have sensors that monitor the tire
pressures in all four tires. The tire pressure mon-
itor warns you if the pressure drops in one or
more of the tires. The tire pressure monitor only
functions if the corresponding sensors are
installed in all wheels.
Information on tire pressures is displayed in the
multifunction display. After a few minutes of
driving, the current tire pressure of each tire is
shown in the Serv. menu of the multifunction
display, see illustration (example).
For information on the message display, refer to
the "Checking the tire pressure electronically"
section ( Y
page 291).Tire pressure 289
Wheels and tires Z

the information on display messages
( Y
page 209).
It may take up to ten minutes for a malfunction
of the tire pressure monitor to be indicated. A
malfunction will be indicated by the tire pres-
sure warning lamp flashing for approximately
one minute and then remaining lit. When the
malfunction has been rectified, the tire pressure
warning lamp goes out after a few minutes of
driving.
The tire pressure values indicated by the on-
board computer may differ from those meas-
ured at a gas station with a pressure gauge. The
tire pressures shown by the on-board computer
refer to those measured at sea level. At high
altitudes, the tire pressure values indicated by a
pressure gauge are higher than those shown by
the on-board computer. In this case, do not
reduce the tire pressures.
The operation of the tire pressure monitor can
be affected by interference from radio transmit-
ting equipment (e.g. radio headphones, two-way
radios) that may be being operated in or near the
vehicle.
Checking the tire pressure electroni-
cally X
Make sure that the SmartKey is in position 2
in the ignition lock ( Y
page 121).X
Press Y or e on the steering wheel to
select the Serv. menu.X
Press the c or d button to select
Tire Pressure .X
Press the v button.
The current tire pressure of each tire is shown
in the multifunction display.
If the vehicle was parked for longer than
20 minute s, the Tire pressure will be
displayed after driving a few minutes
message is shown.
After a teach-in process, the tire pressure mon-
itor automatically detects new wheels or new
sensors. As long as a clear allocation of the tire
pressure value to the individual wheels is not
possible, the Tire Pressure Monitor Active
message is shown instead of the tire pressure
display. The tire pressures are already being
monitored. Tire pressure monitor warning mes-
sages If the tire pressure monitor detects a pressure
loss in one or more tires, a warning message is
shown in the multifunction display. The yellow
tire pressure warning lamp then lights up. R
If the Please Correct Tire Pressure
message appears in the multifunction display,
the tire pressure in at least one tire is too low.
The tire pressure must be corrected when the
opportunity arises. R
If the Check Tire Pressure message
appears in the multifunction display, the tire
pressure in one or more tires has dropped
significantly. The tires must be checked. R
If the Tire Pressure Warning Tire Fail‐
ure message appears, the tire pressure in one
or more tires has dropped suddenly. The tires
must be checked.
Observe the instructions and safety notes in the
display messages in the "Tires" section
( Y
page 209).
If the wheel positions on the vehicle are rotated,
the tire pressures may be displayed for the
wrong positions for a short time. This is rectified
after a few minutes of driving, and the tire pres-
sures are displayed for the correct positions.
Restarting the tire pressure monitor When you restart the tire pressure monitor, all
existing warning messages are deleted and the
warning lamps go out. The monitor uses the cur-
rently set tire pressures as the reference values
for monitoring. In most cases, the tire pressure
monitor will automatically detect the new refer-
ence values after you have changed the tire
pressure. However, you can also set reference
values manually as described here. The tire
pressure monitor then monitors the new tire
pressure values. X
Set the tire pressure to the value recommen-
ded for the corresponding driving situation on
the Tire and Loading Information placard on
the driver's side B-pillar ( Y
page 285).
You can find more tire pressure values for
various operating conditions in the tire pres-
sure table inside the fuel filler flap
( Y
page 138). X
Make sure that the tire pressure is correct on
all four wheels.Tire pressure 291
Wheels and tires Z

X
Make sure that the SmartKey is in position 2
in the ignition lock ( Y
page 121).X
Press Y or e on the steering wheel to
select the Serv. menu.X
Press the c or d button to select
Tire Pressure .X
Press the v button.
The multifunction display shows the current
tire pressure for each tire or the Tire pres‐
sure will be displayed after driving
a few minutes message.X
Press the d button.
The multifunction display shows the Use
Current Pressures as New Reference
Values message.
If you wish to confirm the restart: X
Press the v button.
The Tire Press. Monitor Restarted mes-
sage appears in the multifunction display.
After driving for a few minutes, the system
checks whether the current tire pressures are
within the specified range. The new tire pres-
sures are then accepted as reference values
and monitored.
If you wish to cancel the restart: X
Press the 8 button.
The tire pressure values stored at the last
restart will continue to be monitored.
Radio type approval for the tire pres-
sure monitor Country Radio type approval number
USA FCC ID: MRXMW2433A
FCC ID: MRXGG4
FCC ID: MRXMC34MA4
Canada IC: 2546A-MW2433A
IC: 2546A-GG4
IC: 2546A-MC34MA4
Loading the vehicle
Instruction labels for tires and loads
G WARNING
Overloaded tires can overheat, causing a
blowout. Overloaded tires can also impair the steering and driving characteristics and lead
to brake failure. There is a risk of accident.
Observe the load rating of the tires. The load
rating must be at least half of the GAWR of
your vehicle. Never overload the tires by
exceeding the maximum load.
Two instruction labels on your vehicle show the
maximum possible load.
(1) The Tire and Loading Information placard is
on the B-pillar on the driver's side. The Tire
and Loading Information placard shows the
maximum permissible number of occu-
pants and the maximum permissible vehicle
load. It also contains details of the tire sizes
and corresponding pressures for tires
mounted at the factory.
(2) The vehicle identification plate is on the B-
pillar on the driver's side. The vehicle iden-
tification plate informs you of the gross
vehicle weight rating. It is made up of the
vehicle weight, all vehicle occupants, the
fuel and the cargo. You can also find infor-
mation about the maximum gross axle
weight rating on the front and rear axle.
The maximum gross axle weight rating is
the maximum weight that can be carried by
one axle (front or rear axle). Never exceed
the maximum load or the maximum gross
axle weight rating for the front or rear axle.
C
B-pillar, driver's side292
Loading the vehicle
Wheels and tires

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 ( Y
page 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 X
Stop the vehicle on solid, non-slippery and
level ground. X
Apply the electric parking brake manually. X
Bring the front wheels into the straight-ahead
position. X
Shift the transmission to position P .X
Switch off the engine. X
Vehicles without KEYLESS-GO: remove the
SmartKey from the ignition lock. X
Vehicles 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. X
Vehicles with KEYLESS-GO start-function
or KEYLESS-GO: remove the Start/Stop but-
ton from the ignition lock ( Y
page 121).X
Make sure that the engine cannot be started
via your smartphone ( Y
page 122).X
If included in the vehicle equipment, remove
the tire-change tool kit from the vehicle. X
Safeguard the vehicle against rolling away
( Y
page 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
( Y
page 266).
The folding wheel chock is an additional safety
measure to prevent the vehicle from rolling
away, for example when changing a wheel.302
Changing a wheel
Wheels and tires

Other identifications, for example: R
0 W-30 R
5 W-30 R
5 W-40
Fuel
Important safety notes
G WARNING
Fuel is highly flammable. If you handle fuel
incorrectly, there is a risk of fire and explo-
sion.
You must avoid fire, open flames, creating
sparks and smoking. Switch off the engine
and, if applicable, the auxiliary heating before
refueling.
G WARNING
Fuel is poisonous and hazardous to health.
There is a risk of injury.
You must make sure that fuel does not come
into contact with your skin, eyes or clothing
and that it is not swallowed. Do not inhale fuel
vapors. Keep fuel away from children.
If you or others come into contact with fuel,
observe the following: R
Wash away fuel from skin immediately
using soap and water. R
If fuel comes into contact with your eyes,
immediately rinse them thoroughly with
clean water. Seek medical assistance with-
out delay. R
If fuel is swallowed, seek medical assis-
tance without delay. Do not induce vomit-
ing. R
Immediately change out of clothing which
has come into contact with fuel. Tank capacity Model Total capa-
city
CLA 250
13.2 US gal
(50.0 l)
Al l ot her models
14.8 US gal
(56.0 l)
Model Of which
reserve
Mercedes ‑ AMG vehicles
Approx.
2.1 US gal
(8.0 l)
All other models
Approx.
1.6 US gal
(6.0 l)
Gasoline
Fuel grade
! Do not use diesel to refuel vehicles with a
gasoline engine. Do not switch on the ignition
if you accidentally refuel with the wrong fuel.
Otherwise, the fuel will enter the fuel system.
Even small amounts of the wrong fuel could
result in damage to the fuel system and the
engine. Notify a qualified specialist workshop
and have the fuel tank and fuel lines drained
completely.
! Only refuel using unleaded premium grade
gasoline with at least 91 AKI/95 RON.
i E10 fuel contains up to 10% bioethanol.
Your vehicle is E10-compatible. You can
refuel your vehicle using E10 fuel.
! Only use the fuel recommended. Operating
the vehicle with other fuels can lead to dam-
age to the fuel system, engine and exhaust
system.
! Do not use the following: R
E15 (gasoline with 15% ethanol) R
E85 (gasoline with 85% ethanol) R
E100 (1 00% ethanol) R
M15 (gasoline with 15% methanol) R
M30 (gasoline with 30% methanol) R
M85 (gasoline with 85% methanol)310
Service products and filling capacities
Technical data