engine MERCEDES-BENZ A CLASS 2012 Workshop Manual

i
If indicator lamp ; is off, the ECO start/
stop function has been deactivated man-
ually or as the result of a malfunction. The
engine will then not be switched off auto-
matically when the vehicle stops. 148
Driving
Driving and parking

Problems with the engine
Problem Possible causes/consequences and
M SolutionsThe engine does not
start. The HOLD function or DISTRONIC PLUS is activated.
X
Deactivate the HOLD function (Y page 179) or DISTRONIC
PLUS (Y page 173).
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.
X Turn the key back to position 0 in the ignition lock before
attempting to start the engine again.
X Try to start the engine again (Y page 143). Avoid excessively
long

and frequent attempts to start the engine, as this will drain
the battery.
If the engine does not start after several attempts:
X Consult a qualified specialist workshop. The engine does not
start.

The starter motor
can be heard. The
reserve fuel warning
lamp is lit and the fuel
gauge display shows 0. The fuel tank is empty.
X
Refuel the vehicle. 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 308).
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. a Mercedes-Benz
Service Centre. Driving
149
Driving and parking Z

Problem Possible causes/consequences and
M SolutionsVehicles with a petrol
engine:
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 display is showing
more than 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 288). Observe the warning
notes as you do so and top up the coolant if necessary. If the coolant level is correct, the engine radiator fan may be faulty.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
X
If the coolant temperature is below 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in
mountainous terrain and stop-start traffic. Manual transmission
Gear lever
! Only engage gear when the clutch pedal
is depressed.
! When shifting to 5th and 6th gear, you
must

press the shift lever to the right. Oth-
erwise, you could shift unintentionally into
3rd or 4th gear and damage the engine or
transmission.
If you shift down at too high a speed (trans-
mission braking), this can cause the engine
to overrev, leading to engine damage.
Do not use the clutch bite point to keep the
vehicle stationary on uphill gradients.
There is otherwise a risk of damaging the
clutch.
! On long and steep downhill gradients,
especially if the vehicle is laden or towing a trailer, you must shift into gear
1, 2 or 3
in
good time. This uses the engine's braking
effect. This relieves the load on the brake
system and prevents the brakes from over-
heating and wearing too quickly. Gear lever
k
Reverse gear
1 to 6 Forward gears150
Manual transmission
Driving and parking

Shifting to neutral (N)
X
Depress the clutch pedal fully.
X Move the gear lever to position N:. Engaging reverse gear
! Only shift into reverse gear R when the
vehicle is stationary. Otherwise, you could
damage the transmission.
X Pull the gear lever up, push it to the left and
then pull it back.
i The ECO start/stop function is not avail-
able when reverse gear is engaged.
For further information on the ECO start/
stop function, see ( Y page 146).Gearshift recommendation
The gearshift recommendations assist you in
adopting an economical driving style. The rec-
ommended gear is shown in the multifunction
display. X
Shift gear according to gearshift recom-
mendation : when shown in the multi-
function display of the instrument cluster. Automatic transmission
Important safety notes
G
WARNING
If the engine speed is above the idling speed
and you engage transmission position D or
R,

the vehicle could pull away suddenly. There
is a risk of an accident.
When engaging transmission position D or R,
always firmly depress the brake pedal and do
not simultaneously accelerate. G
WARNING
The automatic transmission switches to neu-
tral
position N when 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.
i 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 P and
R apply the electric parking brake DIRECT SELECT lever
Overview of transmission positions All vehicles (except AMG vehicles):
the
DIRECT SELECT lever is on the right of the
steering column.
Information about the selector lever on AMG
vehicles ( Y page 153). Automatic transmission
151Driving and parking Z

j
Park position with parking lock
k Reverse gear
i Neutral
h Drive
i The DIRECT SELECT lever always returns
to its original position. The current trans-
mission
position P, R, N or D appears in the
transmission position display
(Y page 152) in the multifunction display.
Transmission position and drive pro-
gram display The current transmission position and drive
program appear in the multifunction display.
:
Transmission position display
; Drive program display
i The arrows in the transmission position
display

show how and into which transmis-
sion positions you can change using the
DIRECT SELECT lever.
! 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 D and drive program E or
S. Engaging park position P X
Push the DIRECT SELECT lever in the direc-
tion of arrow P.
Transmission

position display P is shown in
the multifunction display.
i When you engage park position P, make
sure

that the transmission position display
shows P in the multifunction display.
i You can only engage park position P when
the vehicle is stationary.
i The automatic transmission shifts into
park position P automatically:
R if you open the driver's door while the
vehicle is stationary in transmission posi-
tion D or R
R if you open the door while travelling at
very low speeds in transmission position
D or R
In addition, a warning tone sounds and a
display message is shown.
i Depressing the brake and pushing the
DIRECT SELECT lever up or down disen-
gages the parking lock. The transmission is
in N neutral.
At transmission fluid temperatures below
Ò20 †, you can only shift out of park posi-
tion P into another transmission position
when the engine is running.
In order to shift from park position P
directly into R or D:
R depress the brake pedal and
R push the DIRECT SELECT lever up or
down past the first point of resistance
! If the engine speed is too high, do not shift
the automatic transmission directly from
D to R, from R to D or directly to P. Other-
wise, the automatic transmission could be
damaged. 152
Automatic transmission
Driving and parking

A
Neutral
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:
only shift the transmission to posi-
tion N if the vehicle is in danger of
skidding, e.g. on icy roads.
When you switch off the engine, the
automatic transmission automati-
cally shifts into neutral N.7
Drive
The automatic transmission
changes gear automatically. All
forward gears are available.
Changing gear
The
automatic transmission shifts to the indi-
vidual gears automatically when it is in trans-
mission position D. Gearshifting is deter-
mined by:
R the selected drive program ( Y page 155)
R the position of the accelerator pedal
R the road speed Driving tips
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
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 vehicle Shift to P Leave engine
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: the Trans. oil overhea‐
ted Drive on with care display message
appears in the multifunction display.
Do not hold the vehicle stationary on uphill
gradients by depressing the accelerator
pedal. Instead, only ever hold the vehicle sta-
tionary on uphill gradients by:
R depressing the brake pedal
R activating the HOLD function
R engaging the electric parking brake
Kickdown AMG vehicles:
it
is only possible to use kick-
down in temporary manual drive program M.
For further information on the manual drive
program M, see ( Y page 156).
Use kickdown for maximum acceleration:
X Depress the accelerator pedal beyond the
pressure point.
The 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.154
Automatic transmission
Driving and parking

Towing a trailer
Trailer towing is not permissible on the fol-
lowing models:
R
A 45 AMG 4MATIC
R Vehicles with the AMG Sports package
X Drive in the middle of the engine speed
range on uphill gradients.
X Depending on the uphill or downhill gradi-
ent,
select a lower gear (Y page 166), even
if cruise control, DISTRONIC PLUS, or
SPEEDTRONIC are activated. Program selector button
General notes The program selector button allows you to
choose between drive programs with differ-
ent driving characteristics.
Example: program selector button
E Economy Comfortable, economical
driving
S Sport Sporty driving style
M Manual Manual gearshifting
X
Press program selector button : repeat-
edly

until the letter for the desired gearshift
program appears in the multifunction dis-
play.
i The automatic transmission switches to
automatic drive program E each time the
engine is started. i
For further information on the automatic
drive program, see

(Y page 156).
AMG vehicles C Controlled
Efficiency Comfortable, economical
driving
S Sport Sporty driving style
M Manual Manual gearshifting
X
Press program selector button : repeat-
edly

until the letter for the desired gearshift
program appears in the multifunction dis-
play.
i The automatic transmission switches to
automatic drive program C each time the
engine is started.
i For further information on the automatic
drive program, see

(Y page 156). Automatic transmission
155
Driving and parking Z

Steering wheel gearshift paddles
:
Left steering wheel gearshift paddle
(shifts down)
; Right steering wheel gearshift paddle
(shifts up)
In drive program M, you can change gear
yourself using the steering wheel gearshift
paddles.
If
you pull the left or right steering wheel gear-
shift paddle when in automatic drive program
E (drive program C on AMG vehicles) or S, the
automatic transmission shifts into drive pro-
gram M for a limited time. Depending on
which gearshift paddle is pulled, the auto-
matic transmission immediately shifts into
the next gear down or up.
AMG vehicles: you can activate drive pro-
gram M RACE START (Y page 181) using the
steering wheel gearshift paddles.
i You can only change gear with the steer-
ing wheel gearshift paddles when the trans-
mission is in position D.
i For further information on the manual
drive program, see ( Y page 156).Automatic drive program
Drive program E (drive program C on AMG
vehicles) is characterised by the following:
R comfort-oriented engine settings.
R optimal fuel consumption resulting from
the automatic transmission shifting up
sooner. R
the vehicle pulling away more gently in
forward

and reverse gears unless the accel-
erator 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 S is characterised by the fol-
lowing:
R sporty engine settings.
R the automatic transmission shifting up
later.
R as a result of the later automatic transmis-
sion shift points, the fuel consumption pos-
sibly being higher. Manual drive program
Introduction In manual drive program
M, you can change
gear yourself by using the steering wheel
gearshift paddles. For this, the transmission
must be in position D. The gear currently
selected and engaged is shown in the multi-
function display.
Manual drive program M differs from drive
programs E (drive program C on AMG vehi-
cles) and S with regard to spontaneity,
responsiveness and smoothness of gear
changes. Gear Driving situations
=
To use the engine's braking effect156
Automatic transmission
Driving and parking

5
To 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 Activating the manual drive program
Activating permanently
X
Press the program selector button
(Y

page 155) repeatedly until M appears in
the multifunction display.
Manual drive program M remains active
until drive program E (drive program C on
AMG vehicles) or S is engaged.
Activating temporarily
X Pull the right or left steering wheel gearshift
paddle

(Y page 156).
M is shown in the multifunction display.
Manual drive program M is temporarily
active. Depending on which gearshift pad-
dle is pulled, the automatic transmission
immediately shifts into the next gear down
or up.
i When manual drive program M is activa-
ted via the steering wheel gearshift pad-
dles, the temporarily active manual drive
program M will be deactivated automati-
cally after a limited time, if the driving sit-
uation permits. The automatic transmis-
sion switches to the previously activated
drive program E (drive program C on AMG
vehicles) or S. When driving on downhill
gradients, the temporarily active manual
drive program M

will only be deactivated if
the accelerator pedal is depressed while
the vehicle is rolling downhill. Shifting up X
Pull the right-hand steering wheel gearshift
paddle

(Y page 156).
The automatic transmission shifts up to the
next gear.
i All vehicles (except AMG vehicles): in
order to prevent engine damage the auto-
matic

transmission automatically shifts up:
R if the maximum engine speed on the cur-
rently engaged gear is reached and
R you depress the accelerator pedal.
AMG vehicles:
! In manual gearshift program M, the auto-
matic transmission does not shift up auto-
matically even when the engine limiting
speed for the current gear is reached.
When the engine limiting speed is reached,
the fuel supply is cut to prevent the engine
from overrevving. You must make sure that
the engine speed does not reach the red
area of the rev counter. Otherwise, there is
a risk of engine damage.
AMG vehicles !
In
manual gearshift program M, the auto-
matic transmission does not shift up auto-
matically even when the engine limiting
speed for the current gear is reached.
When the engine limiting speed is reached,
the fuel supply is cut to prevent the engine
from overrevving. You must make sure that
the engine speed does not reach the red
area of the rev counter. Otherwise, there is
a risk of engine damage. :
Gear indicator
; Upshift indicator Automatic transmission
157
Driving and parking Z

Before the engine speed reaches the red area,
an
upshift indicator will be shown in the mul-
tifunction display.
X If the colour in the speedometer multifunc-
tion

display changes to red and the UP dis-
play message is shown, shift up a gear.
Downshifting X
Pull the left-hand steering wheel gearshift
paddle

(Y page 156).
The automatic transmission shifts down to
the next gear.
i If you slow down or stop without shifting
down, the automatic transmission auto-
matically shifts down.
i For maximum acceleration, pull the left-
hand steering wheel gearshift paddle until
the

transmission selects the optimum gear
for the current speed.
i If the engine exceeds the maximum
engine speed when shifting down, the auto-
matic transmission protects against engine
damage by not shifting down.
Kickdown AMG vehicles:
it
is only possible to use kick-
down in temporary manual drive program M.
You can also use kickdown for maximum
acceleration in manual drive program M.
X Depress the accelerator pedal beyond the
pressure point.
The transmission shifts to a lower gear
depending on the engine speed.
X Shift back up once the desired speed is
reached.
i During kickdown, you cannot shift gears
using

the steering wheel gearshift paddles.
i If you apply full throttle, the automatic
transmission shifts up to the next gear
when the maximum engine speed is
reached. This prevents the engine from
overrevving. Deactivating the manual drive program X
Press the program selector button
(Y page 155) repeatedly until E or S
appears in the multifunction display.
Deactivating the temporary manual drive
program
X Pull and hold the right steering wheel gear-
shift paddle until the automatic transmis-
sion shifts into the last active automatic
drive program E (drive program C on AMG
vehicles) or S.
i When manual drive program M is deacti-
vated, the automatic transmission in auto-
matic

drive program E (drive program C on
AMG vehicles) or S may shift from the cur-
rent gear into a higher or lower gear. This
is dependent on the position of the accel-
erator pedal, speed and load. 158
Automatic transmission
Driving and parking