brake MERCEDES-BENZ CLA-Class 2015 C117 Service Manual

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

Problems with fuel and the fuel tank
Problem
Possible causes/consequences and
M
MSolutions Fuel is leaking from the
vehicle. The fuel line or the fuel tank is faulty.
G WARNING
Risk of explosion or fire. X Turn the SmartKey to position 0immediately and remove it
(Y page 141).
X Do not restart the engine under any circumstances.
X Consult a qualified specialist workshop. The fuel filler flap can-
not be opened. The fuel filler flap is not unlocked.
X Unlock the vehicle (Y page 74). The SmartKey battery is discharged or nearly discharged.
X Unlock the vehicle using the mechanical key (Y page 76).The fuel filler flap is unlocked, but the opening mechanism is jam-
med.
X Consult a qualified specialist workshop. Parking
Important safety notes
G
WARNING
Flammable material such as leaves, grass or
twigs may ignite if they come into contact with hot parts of the exhaust system or exhaust
gas flow. There is a risk of fire.
Park the vehicle so that no flammable mate-
rials come into contact with parts of the vehi- cle which are hot. Take particular care not to
park on dry grassland or harvested grain
fields. G
WARNING
If you leave children unsupervised in the vehi- cle, they could set it in motion by, for example:
R release the parking brake.
R shift the automatic transmission out of the
parking position P.
R start the engine. In addition, they may operate vehicle equip-
ment and become trapped. 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 unsupervised in the vehicle.
! Always secure the vehicle correctly
against rolling away. Otherwise, the vehicle
or its drivetrain could be damaged.
To ensure that the vehicle is secured against
rolling away unintentionally:
R the electric parking brake must be applied.
R the transmission must be in position Pand
the transmission position display must
show P.
R the SmartKey must be removed from the
ignition lock.
R on uphill or downhill gradients, the front
wheels must be turned towards the curb. 160
ParkingDriving and parking

Switching off the engine
Important safety notes 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.
Vehicles with automatic transmission X
Apply the electric parking brake.
X All vehicles (except AMG vehicles): shift
the transmission to position P.X
AMG vehicles: press button:.
X With the SmartKey: turn the SmartKey to
position 0in the ignition lock and remove it.
The immobilizer is activated.
X With the Start/Stop button: press the
Start/Stop button (Y page 141).
The engine stops and all the indicator
lamps in the instrument cluster go out.
When the driver's door is closed, this cor-
responds to key position 1. When the driv-
er's door is open, this corresponds to key
position 0: "Key removed".
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.
X Release the electric parking brake.
X Switch off the ignition and leave the Smart-
Key in the ignition lock.
If you attempt to turn off the engine when the selector lever is not in position P:
R a message appears in the multifunction dis-
play
R a warning signal sounds Parking
161Driving and parking Z

Electric parking brake
General notes G
WARNING
If you leave children unsupervised in the vehi- cle, they could set it in motion by, for example:
R release the parking brake.
R shift the automatic transmission out of the
parking position P.
R start the engine.
In addition, they may operate vehicle equip-
ment and become trapped. 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 unsupervised in the vehicle.
The function of the electric parking brake is
dependent on the on-board voltage. If the on-
board voltage is low or there is a malfunction in the system, it may not be possible to apply
the released parking brake.
X If this is the case, only park the vehicle on
level ground and secure it to prevent it roll- ing away.
X Shift the automatic transmission to posi-
tion P.
It may not be possible to release an applied
parking brake if the on-board voltage is low or
there is a malfunction in the system. Contact a qualified specialist workshop.
The electric parking brake performs a func-
tion test at regular intervals while the engine
is switched off. The sounds that can be heard
while this is occurring are normal. Applying/releasing manually X
To engage: push handle :.
When the electric parking brake is applied, the red F(USA only) or !(Canada
only) indicator lamp lights up in the instru-
ment cluster.
The electric parking brake can also be
applied when the SmartKey is removed.
X To release: pull handle:.
The red F(USA only) or !(Canada
only) indicator lamp in the instrument clus-
ter goes out.
The electric parking brake can only be
released:
R when the SmartKey is in position 1or 2in
the ignition lock (Y page 141) or
R if the ignition was switched on using the
Start/Stop button
Applying automatically The electric parking brake is automatically
applied when the transmission is in position
P
and:
R the engine is switched off or
R the driver is not wearing a seat belt and the
driver's door is opened.
To prevent the electric parking brake from
being automatically applied, pull handle :.162
ParkingDriving and parking

The electric parking brake is also engaged
automatically if:
R DISTRONIC PLUS brings the vehicle to a
standstill or
R the HOLD function is keeping the vehicle
stationary
R Active Parking Assist is keeping the vehicle
stationary
In addition, at least one of the following con-
ditions must be fulfilled:
R there is a system malfunction.
R the power supply is insufficient.
R the vehicle is stationary for a lengthy
period.
The red F(USA only) or !(Canada
only) indicator lamp in the instrument cluster goes out.
The electric parking brake is not automati-
cally engaged if the engine is switched off by
the ECO start/stop function.
Releasing automatically Your vehicle's electric parking brake is auto-
matically released if all of the following con-
ditions are met:
R the engine is running.
R the transmission is in position Dor R.
R the seat belt has been fastened.
R you depress the accelerator pedal.
If the transmission is in position R, the trunk
lid must be closed.
If your seat belt is not fastened, the following conditions must be fulfilled to automatically
release the electric parking brake:
R the driver's door is closed.
R you have shifted out of transmission posi-
tion Por you have previously driven faster
than 2 mph (3 km/h).
Ensure that you do not depress the acceler-
ator pedal unintentionally. Otherwise the
parking brake will be released and the vehicle will start to move. Emergency braking The vehicle can also be braked during an
emergency by using the electric parking
brake.
X While driving, push handle :of the electric
parking brake (Y page 162).
The vehicle is braked as long as you keep
handle :of the electric parking brake
pressed. The longer the electric parking
brake handle :is depressed, the greater
the braking force.
During braking:
R a warning tone sounds
R the Release park. brake
Release park. brake message
appears
R the red F(USA only) or !(Canada
only) indicator lamp in the instrument clus- ter flashes
When the vehicle has been braked to a stand- still, the electric parking brake is engaged. Parking the vehicle for a long period
If you leave the vehicle parked for longer than
four weeks, the battery may be damaged by
exhaustive discharging.
If you leave the vehicle parked for longer than
six weeks, the vehicle may suffer damage as a result of lack of use.
X Visit a qualified specialist workshop and
seek advice.
i You can obtain information about trickle
chargers from a qualified specialist work-
shop. Driving tips
General notes
Important safety notes G
WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available Driving tips
163Driving and parking
Z

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 you operate mobile communication equip-
ment while driving, you will be distracted from traffic conditions. You could also lose controlof the vehicle. There is a risk of an accident.
Only operate this equipment when the vehicleis stationary.
Observe the legal requirements for the coun- try in which you are driving. Some jurisdic-
tions prohibit the driver from using a mobile
phone while driving a vehicle.
If you make a call while driving, always use
hands-free mode. Only operate the telephone
when the traffic situation permits. If you are
unsure, pull over to a safe location and stop
before operating the telephone.
Bear in mind that at a speed of only 30 mph
(approximately 50 km/h), the vehicle covers
a distance of 44 ft (approximately 14 m) per
second.
Drive sensibly – save fuel Observe the following tips to save fuel:
R The tires should always be inflated to the
recommended tire pressure.
R Remove unnecessary loads.
R Remove roof racks when they are not nee-
ded.
R Warm up the engine at low engine speeds.
R Avoid frequent acceleration or braking.
R Have all maintenance work carried out as
indicated by the service intervals in the
Maintenance Booklet or by the service
interval display.
Fuel consumption also increases when driv-
ing in cold weather, in stop-start traffic and in
hilly terrain. Drinking and driving G
WARNING
Drinking and driving and/or taking drugs and driving are very dangerous combinations.
Even a small amount of alcohol or drugs can
affect your reflexes, perceptions and judg-
ment.
The possibility of a serious or even fatal acci-
dent is greatly increased when you drink or
take drugs and drive.
Do not drink or take drugs and drive or allow
anyone to drive who has been drinking or tak-
ing drugs.
Emission control 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.
Certain engine systems are designed to keep
the level of poisonous components in exhaust fumes within legal limits.
These systems only work at peak efficiency if they are serviced exactly in accordance with
the manufacturer's specifications. For this
reason, only have work on the engine carried
out by qualified and authorized Mercedes-
Benz technicians.
The engine settings must not be changed
under any circumstances. Furthermore, all
specific service work must be carried out at
regular intervals and in accordance with the
Mercedes-Benz service requirements. Details
can be found in the Maintenance Booklet. 164
Driving tipsDriving and parking

ECO display
The ECO display provides feedback on how
economical your driving characteristics are.
The ECO display assists you in achieving the
most economical driving style for the selec-
ted settings and prevailing conditions. Your
driving style can significantly influence the
vehicle's consumption.
The ECO display consists of three bars:
R Acceleration
Acceleration
R Constant Constant
R Coasting
Coasting
The percent value is the average value of the three bars. The three bars and the mean value
begin at the value of 50%. A higher percent-
age indicates a more economical driving
style.
The ECO display does not indicate the actual fuel consumption. A fixed percentage count
in the ECO display does not indicate a fixed
consumption.
Apart from driving style, consumption is
dependent on many factors such as, e.g.:
R load
R tire pressure
R cold start
R choice of route
R electrical consumers switched on
These factors are not included in the ECO dis-
play.
The evaluation of your driving style is carried
out using the following three categories: R
Acceleration
Acceleration (evaluation of all accelera-
tion processes):
- The bar fills up: moderate acceleration,
especially at higher speeds
- The bar empties: sporty acceleration
R Constant
Constant (assessment of driving behavior
at all times)
- The bar fills up: constant speed and
avoidance of unnecessary acceleration
and deceleration
- The bar empties: fluctuations in speed
R Coasting Coasting (assessment of all deceleration
processes)
- The bar fills up: anticipatory driving,
keeping your distance and early release
of the accelerator. The vehicle can coast without use of the brakes.
- The bar empties: frequent braking
An economical driving style specially requires driving at moderate engine speeds.
To achieve a higher value in the categories
Acceleration Acceleration andConstant Constant:
R observe the gearshift recommendations.
R drive in drive program E.
On long journeys at a constant speed, e.g. on
the highway, only the bar for Constant
Constantwill
change.
The ECO display summarizes the driving char- acteristics from the start of the journey to its completion. For this reason, the bars change
dynamically at the beginning of the journey.
On longer journeys, there are fewer changes. For more dynamic changes, carry out a man- ual reset.
For further information on the ECO display,
see (Y page 204). Braking
Important safety notes G
WARNING
If you shift down on a slippery road surface in an attempt to increase the engine's braking Driving tips
165Driving and parking
Z

effect, the drive wheels could lose their grip.
There is an increased danger of skidding and
accidents.
Do not shift down for additional engine brak-
ing on a slippery road surface.
Downhill gradients !
On long and steep gradients, you must
reduce the load on the brakes by shifting to
a lower gear in good time. This allows you to
take advantage of the engine's braking
effect. For this, you need to have selected
manual drive program M. This helps you to
avoid overheating the brakes and wearing
them out excessively.
When you take advantage of the engine's
braking effect, a drive wheel may not turn
for some time, e.g. on a slippery road sur-
face. This could cause damage to the drive train. This type of damage is not covered bythe Mercedes-Benz warranty.
Briefly depressing the accelerator pedal on
downhill gradients while the manual drive
program Mis temporarily activated: the auto-
matic transmission may switch to the last
active automatic drive program Eor S. The
automatic transmission may shift to a higher
gear. This can reduce the engine's braking
effect.
Heavy and light loads G
WARNING
If you rest your foot on the brake pedal while
driving, the braking system can overheat. This increases the stopping distance and can even
cause the braking system to fail. There is a
risk of an accident.
Never use the brake pedal as a footrest. Never
depress the brake pedal and the accelerator
pedal at the same time.
! Depressing the brake pedal constantly
results in excessive and premature wear to
the brake pads. If the brakes have been subjected to a heavy
load, do not stop the vehicle immediately.
Drive on for a short while. This allows the air-
flow to cool the brakes more quickly.
Wet roads If you have driven for a long time in heavy rain
without braking, there may be a delayed reac- tion from the brakes when braking for the firsttime. This may also occur after the vehicle has
been washed or driven through deep water.
You have to depress the brake pedal more
firmly. Maintain a greater distance from the
vehicle in front.
After driving on a wet road or having the vehi-
cle washed, brake firmly while paying atten-
tion to the traffic conditions. This will warm up the brake discs, thereby drying them more
quickly and protecting them against corro-
sion.
Limited braking performance on salt-
treated roads If you drive on salted roads, a layer of salt
residue may form on the brake discs and
brake pads. This can result in a significantly
longer braking distance.
R In order to prevent any salt build-up, apply
the brakes occasionally while paying atten-
tion to the traffic conditions.
R Carefully depress the brake pedal and the
beginning and end of a journey.
R Maintain a greater distance to the vehicle
ahead.
Servicing the brakes !
If the red brake warning lamp lights up in
the instrument cluster and you hear a warn- ing tone while the engine is running, the
brake fluid level may be too low. Observe
additional warning messages in the multi-
function display.
The brake fluid level may be too low due to brake pad wear or leaking brake lines. 166
Driving tipsDriving and parking

Have the brake system checked immedi-
ately. This work should be carried out at a
qualified specialist workshop.
! A function or performance test should
only be carried out on a 2-axle dynamom-
eter. If you are planning to have the vehicle tested on such a dynamometer, contact an
authorized Mercedes-Benz Center to
obtain further information first. Otherwise,
you could damage the drive train or the
brake system.
! As the ESP ®
system operates automati-
cally, the engine and the ignition must be
switched off (the SmartKey must be in posi-
tion 0or 1in the ignition lock) if:
R the electric parking brake is tested on a
brake dynamometer (for a maximum of
ten second s)
R the vehicle is towed with the front axle
raised.
Braking triggered automatically by ESP ®
may seriously damage the brake system.
All checks and maintenance work on the
brake system must be carried out at a quali-
fied specialist workshop. Consult a qualified
specialist workshop to arrange this.
Have brake pads installed and brake fluid
replaced at a qualified specialist workshop.
If the brake system has only been subject to
moderate loads, you should test the function- ality of your brakes at regular intervals.
You can find a description of Brake Assist
(BAS) on (Y page 64).
Mercedes-Benz recommends that you only
have brake pads/linings installed on your
vehicle which have been approved for
Mercedes-Benz vehicles or which correspond to an equivalent quality standard. Brake
pads/linings which have not been approved
for Mercedes-Benz vehicles or which are not
of an equivalent quality could affect your vehi-
cle's operating safety.
Mercedes-Benz recommends that you only
use brake fluid that has been specially
approved for your vehicle by Mercedes-Benz, or which corresponds to an equivalent quality
standard. Brake fluid which has not been
approved for Mercedes-Benz vehicles or
which is not of an equivalent quality could
affect your vehicle's operating safety.
Checking brake lining thickness You can measure the break pad/lining thick-
ness using a test gage. Color-coding (green or
red) on the test gage allows you to determine whether the brake pad/lining thickness is still
sufficient. The test gage is in the vehicle docu-
ment wallet in the glove box. Front wheel Driving
tips
167Driving an d parking Z