2015 MERCEDES-BENZ CLA-Class engine

Problems with the engine
Problem
Possible causes/consequences and
M
MSolutions The engine does not
start. The HOLD function or DISTRONIC PLUS is activated.
X Deactivate the HOLD function (Y page 178) or DISTRONIC
PLUS (Y page 171).
X Try to start the engine again. The engine does not
start. The starter motor
can be heard. R
There is a malfunction in the engine electronics.
R There is a malfunction in the fuel supply.
Before attempting to start the engine again:
X Turn the key to position 0in the ignition lock.
or
X Press the Start/Stop button repeatedly until all indicator lamps
in the instrument cluster go out.
X Try to start the engine again (Y page 143). Avoid excessively
long and frequent attempts to start the engine as these will drain
the battery.
If the engine does not start after several attempts: X Consult a qualified specialist workshop. The engine does not
start. You cannot hear
the starter motor. The on-board voltage is too low because the battery is too weak or
discharged.
X Jump-start the vehicle (Y page 309).
If the engine does not start despite attempts to jump-start it:
X Consult a qualified specialist workshop. The starter motor was exposed to a thermal load that was too high.
X Allow the starter motor to cool down for approximately two
minutes.
X Try to start the engine again.
If the engine still does not start:
X Consult a qualified specialist workshop, e.g. an authorized
Mercedes-Benz Center. Driving
147Driving 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

open the driver's door or front-passenger
door
R the driver's door is opened when the vehi-
cle is stationary or driving at very low speed and the transmission is in position Dor R
Engaging reverse gear R !
Only shift the automatic transmission to
R
when the vehicle is stationary.
X If the transmission is in position Dor N:
push the DIRECT SELECT lever up past the first point of resistance.
X If the transmission is in position P: depress
the brake pedal and push the DIRECT
SELECT lever up past the first point of
resistance.
The ECO start/stop function is not available
when reverse gear is engaged. Further infor-
mation on the ECO start/stop function
(Y page 145).
Shifting to neutral N 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. X
If the transmission is in position Dor R:
push the DIRECT SELECT lever up or down to the first point of resistance.
X If the transmission is in position P: depress
the brake pedal and push the DIRECT
SELECT lever up or down to the first point of
resistance.
If you switch the engine off with the trans-
mission in position Ror D, the automatic
transmission shifts to Nautomatically.
With the SmartKey: if you then open the
driver's door or the front-passenger door or
remove the SmartKey from the ignition, the
automatic transmission shifts to Pautomati-
cally.
With the Start/Stop button: if you then
open the driver's door or the front-passenger door, the automatic transmission shifts to P
automatically.
If you want the automatic transmission to
remain in neutral N, e.g. when having the
vehicle cleaned in an automatic car wash with a towing system:
Using the SmartKey:
X Switch on the ignition.
X Depress the brake pedal and keep it
depressed.
X Shift to neutral N.
X Release the brake pedal.
X Release the electric parking brake.
X Switch off the ignition and leave the Smart-
Key in the ignition lock.
With the Start/Stop button: X Remove the Start/Stop button from the
ignition lock.
X Insert the SmartKey into the ignition lock.
X Switch on the ignition.
X Depress the brake pedal and keep it
depressed.
X Shift to neutral N.
X Release the brake pedal. 150
Automatic transmissionDriving and parking

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

Holding the vehicle stationary on uphill
gradients G
WARNING
If the clutch overheats, the electronic man-
agement system is automatically deactivated. This interrupts the power transmission. The
vehicle may, for example, roll backwards on
gradients. There is a risk of an accident.
Never hold the vehicle stationary on uphill
gradients by depressing the accelerator.
The clutch may overheat if you hold the vehi- cle stationary on uphill gradients by depress- ing the accelerator pedal. If the clutch over-
heats, a warning tone sounds.
All vehicles (except AMG vehicles): the
Stop
Stop Vehicle Vehicle Shift
Shiftto
toP
PLeave
Leave Engine
Engine
Running
Running display message appears in the mul-
tifunction display. You will only be able to
continue your journey once the clutch has
cooled down and the display message in the
multifunction display has disappeared.
AMG vehicles: theTrans. Oil Overhea‐ Trans. Oil Overhea‐
ted Drive on with Care
ted Drive on with Care display message
appears in the multifunction display.
Never hold the vehicle stationary on uphill
gradients by depressing the accelerator.
Instead, only ever hold the vehicle stationary
on uphill gradients by:
R depressing the brake pedal
R activating the HOLD function
R engaging the electric parking brake
Kickdown Use kickdown for maximum acceleration.
X Depress the accelerator pedal beyond the
pressure point.
The automatic transmission shifts to a
lower gear depending on the engine speed.
X Ease off the accelerator pedal once the
desired speed is reached.
The automatic transmission shifts back up.
AMG vehicles: it is only possible to use kick-
down in the automatic drive program and the temporary manual drive program
M. When
manual drive program Mis permanently acti-
vated, kickdown is not possible.
For further information on kickdown in man-
ual drive program M(Y page 155).
Rocking the vehicle free Shifting the transmission repeatedly between
gears Dand Rmay help to free the vehicle if it
has become stuck in slush or snow. The vehi- cle's engine management system limits the
speed to a maximum of 5 mph (9 km/h) when
shifting back and forth. To shift back and forth
between transmission positions Dand R,
move the DIRECT SELECT lever up and down past the point of resistance. Program selector button
The program selector button allows you to
choose between drive programs with differ-
ent driving characteristics. X
All vehicles (except AMG vehicles):
press program selector button :.
The selected drive program appears in the
multifunction display. Automatic transmission
153Driving and parking Z

X
AMG vehicles: press program selector
button :.
The selected drive program appears in the
multifunction display.
When the engine is started, the automatic
transmission always switches to automatic
drive program E(drive program Cin AMG
vehicles).
All vehicles (except AMG vehicles) E
Economy Comfortable, economical
driving
S
Sport Sporty driving style
M
Manual Manual gear shifting
AMG vehicles
C
Controlled
Efficiency Comfortable, economical
driving
S
Sport Sporty driving style
M
Manual Manual gear shifting
For further information on the automatic drive
program, see (Y page 154). Steering wheel paddle shifters
:
Left steering wheel paddle shifter (shifts
down)
; Right steering wheel paddle shifter (shifts
up)
In drive program M, you can change gear
yourself using the steering wheel paddle shift-
ers.
If you pull the left or right steering wheel pad- dle shifter when in automatic drive program E
(drive program Con AMG vehicles) or S, the
automatic transmission shifts into drive pro-
gram Mfor a limited time. Depending on
which paddle shifter is pulled, the automatic
transmission immediately shifts into the next
gear down or up.
AMG vehicles: you can activate drive pro-
gram MRACE START (Y page 180) using the
steering wheel paddle shifters.
You can only change gear with the steering
wheel paddle shifters when the transmission
is in position D.
For further information on the manual drive
program, see (Y page 155). Automatic drive program
Drive program E(drive program Con MAG
vehicles) is characterized by the following:
R comfort-oriented engine settings.
R optimal fuel consumption resulting from
the automatic transmission shifting up
sooner. 154
Automatic transmissionDriving and pa
rking

R
the vehicle pulling away more gently in
forward and reverse gears, unless the
accelerator pedal is depressed fully.
R increased sensitivity. This improves driving
stability on slippery road surfaces, for
example.
R the automatic transmission shifting up
sooner. This results in the vehicle being
driven at lower engine speeds and the
wheels being less likely to spin.
Drive program Sis characterized by the fol-
lowing:
R sporty engine settings.
R the automatic transmission shifting up
later.
R the fuel consumption possibly being higher
as a result of the later automatic transmis- sion shift points. Manual drive program
General information In manual drive program
M, you can change
gear yourself by using the steering wheel pad-
dle shifters. For this, the transmission must
be in position D. The gear currently selected
and engaged is shown in the multifunction
display.
Manual drive program Mdiffers from drive
programs E(drive program Con AMG vehi-
cles) and Swith regard to spontaneity,
responsiveness and smoothness of gear
changes. Gear Driving situations
=
You can use the engine's braking
effect 5
You can use the braking effect of
the engine on downhill gradients
and for driving:
R on steep mountain roads
R in mountainous terrain
R in arduous conditions 4
To use the braking effect of the
engine on extremely steep downhill
gradients and on long downhill
stretches Switching on the manual drive program
Activating permanently
X Press the program selector button
(Y page 153) repeatedly until Mappears in
the multifunction display.
Manual drive program Mremains active
until drive program E(drive program Con
AMG vehicles) or Sis selected.
Activating temporarily X Pull the right or left steering wheel paddle
shifter (Y page 154).
Manual drive program Mis temporarily
active. Depending on which paddle shifter
is pulled, the automatic transmission
immediately shifts into the next gear down
or up.
When manual drive program Mis activated via
the steering wheel paddle shifters, the tem-
porarily active manual drive program Mwill be
deactivated automatically after a limited
time, if the driving situation permits. The auto-
matic transmission switches to the previously activated drive program E(drive program Con
AMG vehicles) or S. When driving on downhill
gradients, the temporarily active manual
drive program Mwill only be deactivated if the
accelerator pedal is depressed while the vehi-
cle is rolling downhill. Automatic transmission
155Driving and parking Z