2015 MERCEDES-BENZ CLA-Class check engine

Useful information
i This Operator's Manual describes all
models and all standard and optional equip- ment of your vehicle available at the time of
publication of the Operator's Manual.
Country-specific differences are possible.
Please note that your vehicle may not be
equipped with all features described. This
also applies to safety-related systems and
functions.
i Read the information on qualified special-
ist workshops (Y page 24). Correct driver's seat position
G
WARNING
You could lose control of your vehicle if you do the following while driving:
R adjust the driver's seat, head restraint,
steering wheel or mirrors
R fasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint, steer-
ing wheel and mirror and fasten your seat belt before starting the engine. X
Observe the safety guidelines on seat
adjustment (Y page 97).
X Make sure that seat =is adjusted prop-
erly.
Manual seat adjustment (Y page 98)
Electrical seat adjustment (Y page 98)
When adjusting the seat, make sure that:
R you are as far away from the driver's air
bag as possible
R you are sitting in a normal upright posi-
tion
R you can fasten the seat belt properly
R you have moved the backrest to an
almost vertical position
R you have set the seat cushion angle so
that your thighs are gently supported
R you can depress the pedals properly
X Check whether the head restraint is adjus-
ted properly (Y page 98).
When doing so, make sure that you have
adjusted the head restraint so that the back of your head is supported at eye level by the
center of the head restraint.
X Observe the safety notes on steering col-
umn adjustment (Y page 102).
X Make sure that steering wheel :is adjus-
ted properly.
Adjusting the steering wheel
(Y page 102)
When adjusting the steering wheel, make
sure that:
R you can hold the steering wheel with your
arms slightly bent
R you can move your legs freely
R you can see all the displays in the instru-
ment cluster clearly
X Observe the safety guidelines for seat belts
(Y page 42).
X Check whether you have fastened seat
belt ;properly (Y page 44). 96
Correct driver's seat positionSeats, steering wheel and mirrors

Problems with the seat heating
Problem
Possible causes/consequences and
M
MSolutions The seat heating has
switched off prema-
turely or cannot be
switched on. The on-board voltage is too low because too many electrical con-
sumers are switched on.
X Switch off electrical consumers that you do not need, such as
the rear window defroster or interior lighting.
Once the battery is sufficiently charged, the seat heating will
switch back on automatically. Steering wheel
Important safety notes
G
WARNING
You could lose control of your vehicle if you do the following while driving:
R adjust the driver's seat, head restraint,
steering wheel or mirrors
R fasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint, steer-
ing wheel and mirror and fasten your seat belt before starting the engine. G
WARNING
Children could injure themselves if they
adjust the steering wheel. There is a risk of
injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never leave children unsupervised in the vehicle. Adjusting the steering wheel
G
WARNING
If the steering wheel is unlocked while the
vehicle is in motion, it could change position
unexpectedly. This could cause you to lose
control of the vehicle. There is a risk of an
accident. Before starting off, make sure the steering
wheel is locked. Never unlock the steering
wheel while the vehicle is in motion. :
Release lever
; To adjust the steering wheel height
= To adjust the steering wheel position
(fore-and-aft adjustment)
X Push release lever :down completely.
The steering column is unlocked.
X Adjust the steering wheel to the desired
position.
X Push release lever :up completely.
The steering column is locked.
X Check if the steering column is locked.
When doing so, try to push the steering
wheel up or down or try to move it in the
fore-and-aft direction. 102
Steering wheelSeats, steering wheel and mirrors

Interior lighting control
General notes In order to prevent the vehicle's battery from
discharging, the interior lighting functions are
automatically deactivated after some time
unless the SmartKey is in position 2in the
ignition lock.
The color and brightness for the ambient
lighting may be set using COMAND or Audio
20 (see the separate operating instructions).
Automatic interior lighting control X
To switch on: set the switch to center
position B.
X To switch off: set the switch to the |
position.
The interior lighting automatically switches
on if you: R unlock the vehicle
R open a door
R remove the SmartKey from the ignition
lock.
The interior light is activated for a short while when the SmartKey is removed from the igni-
tion lock. This delayed switch-off can be
adjusted using COMAND or Audio 20 (see the separate Operator's Manual).
Manual interior lighting control X
To switch the front interior lighting on:
set the switch to the cposition.
X To switch the front interior lighting off:
set the switch to the |position or (if the
door is closed) to the center position.
X To switch the rear interior lighting on/
off: press the ubutton.
X To switch the reading lamps on/off:
press the pbutton. Crash-responsive emergency lighting
The interior lighting is activated automatically
if the vehicle is involved in an accident.
X To switch off the crash-responsive
emergency lighting: press the hazard
warning lamp button.
or X Lock and then unlock the vehicle using the
SmartKey. Replacing bulbs
Important safety notes
Xenon bulbs G
DANGER
Xenon bulbs carry a high voltage. You can get an electric shock if you remove the cover of
the Xenon bulb and touch the electrical con-
tacts. There is a risk of fatal injury.
Never touch the parts or the electrical con-
tacts of the Xenon bulb. Always have work on
the Xenon bulbs carried out at a qualified spe-
cialist workshop.
If your vehicle is equipped with Xenon bulbs,
you can recognize this by the following: the
cone of light from the Xenon bulbs moves
from the top to the bottom and back again
when you start the engine. For this to be
observed, the lights must be switched on
before starting the engine.
Bulbs and lamps are an important aspect of
vehicle safety. You must therefore make sure that these function correctly at all times.
Have the headlamp setting checked regularly.
Other bulbs G
WARNING
Bulbs, lamps and connectors can get very hot when operating. If you change a bulb, you
could burn yourself on these components.
There is a risk of injury.
Allow these components to cool down before changing a bulb. 116
Replacing bulbsLights and windshield wipers

G
WARNING
Unsuitable footwear can hinder correct usage of the pedals, e.g.:
R shoes with thick soles
R shoes with high heels
R slippers
There is a risk of an accident.
Wear suitable footwear to ensure correct
usage of the pedals. G
WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or not at all. This could affect, for example, the power steering and the brake
boosting effect. You will require considerably
more effort to steer and brake. There is a risk of an accident.
Do not switch off the ignition while driving. G
WARNING
If the parking brake has not been fully
released when driving, the parking brake can:
R overheat and cause a fire
R lose its hold function.
There is a risk of fire and an accident. Release
the parking brake fully before driving off.
! Do not warm up the engine with the vehi-
cle stationary. Drive off immediately. Avoid high engine speeds and driving at full throt-
tle until the engine has reached its operat-
ing temperature.
Only shift the automatic transmission to
the desired drive position when the vehicle is stationary.
Where possible, avoid spinning the drive
wheels when pulling away on slippery
roads. You could otherwise damage the
drive train.
! AMG vehicles:
avoid full-load operation
and engine speeds greater than 5000 rpm
when the engine is cold. This helps to pro- tect the engine and avoids uncomfortable
driving. Key positions
SmartKey g
To remove the SmartKey
(shift the transmission to position P)
1 Power supply for some consumers, such
as the windshield wipers
2 Ignition (power supply for all consumers)
and drive position
3 To start the engine
i The SmartKey can be turned in the igni-
tion lock even if it is not the correct Smart- Key for the vehicle. The ignition is not
switched on. The engine cannot be started.
Start/Stop button General notes
Vehicles with KEYLESS-GO are equipped with
SmartKeys featuring the integrated KEYLESS-
GO function and a detachable Start/Stop but-
ton.
A check which periodically establishes a radio connection between the vehicle and the
SmartKey determines whether a valid Smart-Key is in the vehicle. This occurs, for example,
when starting the engine.
When you insert the Start/Stop button into
the ignition lock, the system needs approx-
imately two seconds recognition time. You
can then use the Start/Stop button. Driving
141Driving and parking Z

=
Start/Stop button USA
? Start/Stop button Canada
Removing the Start/Stop button
You can remove the Start/Stop button from
the ignition lock and start the vehicle as nor-
mal using the SmartKey.
You can only switch between Start/Stop but-
ton mode and SmartKey operation when the
vehicle is stationary.
You must also engage park position P.
X Remove Start/Stop button :from ignition
lock ;.
You do not have to remove the Start/Stop
button from the ignition lock when you leave
the vehicle. You should, however, always take the SmartKey with you when leaving the vehi-cle. As long as the SmartKey is in the vehicle:
R the vehicle can be started using the Start/
Stop button
R the electrically powered equipment can be
operated Starting the engine
Important safety notes G
WARNING
If children are left unsupervised in the vehicle, they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment. Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shifting the automatic transmission out of
park position P
R Start the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children. G
WARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces with-
out sufficient ventilation. G
WARNING
Flammable materials introduced through
environmental influence or by animals can
ignite if in contact with the exhaust system or parts of the engine that heat up. There is a risk
of fire.
Carry out regular checks to make sure that
there are no flammable foreign materials in
the engine compartment or in the exhaust
system.
! Do not depress the accelerator when
starting the engine.
General notes During a cold start, the engine runs at higher
speeds to enable the catalytic converter to
reach its operating temperature. The sound of
the engine may change during this time. Driving
143Driving and parking Z

Problem
Possible causes/consequences and
M
MSolutions The engine is not run-
ning smoothly and is
misfiring. There is a malfunction in the engine electronics or in a mechanical
component of the engine management system.
X Only depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic con-
verter and damage it.
X Have the cause rectified immediately at a qualified specialist
workshop. The coolant tempera-
ture gauge shows a
value above 248 ‡
(120 †). The coolant
warning lamp may also
be on and a warning
tone may sound. The coolant level is too low. The coolant is too hot and the engine
is no longer being cooled sufficiently.
X Stop as soon as possible and allow the engine and the coolant to
cool down.
X Check the coolant level (Y page 289). Observe the warning
notes as you do so and add coolant if necessary. Automatic transmission
Important safety notes
G
WARNING
If the engine speed is above the idling speed
and you engage transmission position Dor R,
the vehicle could pull away suddenly. There is a risk of an accident.
When engaging transmission position Dor R,
always firmly depress the brake pedal and do not simultaneously accelerate. G
WARNING
The automatic transmission switches to neu-
tral position Nwhen you switch off the engine.
The vehicle may roll away. There is a risk of an
accident.
After switching off the engine, always switch
to parking position P. Prevent the parked vehi-
cle from rolling away by applying the parking
brake.
Bear in mind that the power transmission
between the engine and the transmission is
interrupted when the engine is switched off. To prevent the vehicle from rolling away:
R when the engine is switched off and the
vehicle is stationary shift the automatic
transmission to park position Pand
R apply the electric parking brake DIRECT SELECT lever
Overview of transmission positions j
Park position with parking lock
k Reverse gear
i Neutral
h Drive 148
Automatic transmissionDriving and parking

All vehicles (except AMG vehicles):
the
DIRECT SELECT lever is on the right of the
steering column.
For information on the selector lever in AMG
vehicles (Y page 151).
The DIRECT SELECT lever always returns to
its original position. The current transmission position P,R, Nor Dappears in the transmis-
sion position display in the multifunction dis-
play (Y page 149).
Transmission position and drive pro-
gram display !
If the transmission position display in the
multifunction display is not working, you
should pull away carefully to check whether the desired transmission position is
engaged. Ideally, you should select trans-
mission position Dand drive program Eor
S. :
Transmission position
; Gear
= Drive program display
The current transmission position and drive
program appear in the multifunction display.
The arrows in the transmission position dis-
play show how and into which transmission
positions you can shift using the DIRECT
SELECT lever.
Engaging park position P !
If the engine speed is too high or the vehi-
cle is moving, do not shift the automatic
transmission directly from Dto R, from Rto
D or directly to P. The automatic transmis-
sion could otherwise be damaged. j
Park position with parking lock
k Reverse gear
i Neutral
h Drive
X Push the DIRECT SELECT lever in the direc-
tion of arrow P.
Transmission position display Pis shown in
the multifunction display.
When you have engaged park position P,
make sure that the transmission position dis-
play shows Pin the multifunction display.
You can only engage park position Pwhen the
vehicle is stationary.
Depressing the brake and pushing the
DIRECT SELECT lever up or down disengages the parking lock. The transmission is in N
neutral.
At transmission fluid temperatures below
Ò4 ‡ (Ò20 †), you can only shift out of park
position Pinto another transmission position
when the engine is running.
In order to shift from park position Pdirectly
into Ror D:
R depress the brake pedal and
R push the DIRECT SELECT lever up or down
past the first point of resistance
Engaging park position P automatically Park position
Pis automatically engaged if:
R you switch off the engine using the Smart-
Key and remove the SmartKey
R you switch off the engine using the Smart-
Key or using the Start/Stop button and Automatic transmission
149Driving and parking Z

Transmission positions
B Park position
This prevents the vehicle from roll- ing away when stopped.
Do not shift the transmission into
position P(Y page 149) unless the
vehicle is stationary. The parking
lock should not be used as a brake when parking. Always apply the
electronic parking brake in addi-
tion to the parking lock in order to
secure the vehicle.
If the vehicle electronics are mal-
functioning, the transmission may
be locked in position P. Have the
vehicle electronics checked imme-
diately at a qualified specialist
workshop.
Park position Pis automatically
engaged if:
R you switch off the engine using
the SmartKey and remove the
SmartKey
R you switch off the engine using
the SmartKey or using the Start/
Stop button and open the driv-
er's door or front-passenger
door
R the driver's door is opened when
the vehicle is stationary or driv-
ing at very low speed and the
transmission is in position Dor R C Reverse gear
Only shift the transmission to R
when the vehicle is stationary. A Neutral
Do not shift the transmission to
N
while driving. Otherwise, the auto-
matic transmission could be dam-
aged.
No power is transmitted from the
engine to the drive wheels.
Releasing the brakes will allow you
to move the vehicle freely, e.g. to
push it or tow it.
If ESP ®
is deactivated or faulty:
shift the transmission to position N
if the vehicle is in danger of skid-
ding, e.g. on icy roads.
If you switch the engine off with the transmission in position Ror D, the
automatic transmission shifts to N
automatically.
! Rolling in neutral
Ncan damage
the drive train. 7 Drive
The automatic transmission
changes gear automatically. All
forward gears are available.
Driving tips
Changing gear The automatic transmission shifts to the indi-
vidual gears automatically when it is in trans-
mission position D. This automatic gear shift-
ing behavior is determined by:
R the selected drive program (Y page 153)
R the position of the accelerator pedal
(Y page 152)
R the road speed
Accelerator pedal position Your style of driving influences how the auto-
matic transmission shifts gear:
R little throttle: early upshifts
R more throttle: late upshifts 152
Automatic transmissionDriving an
d parking