check engine MERCEDES-BENZ CLS-Class 2015 W218 Owner's Guide

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 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 315). 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. Selector lever (AMG vehicles)
Overview of transmission positions j
Park position with parking lock
k Reverse gear
i Neutral
h Drive
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 automatic drive pro-
gram Cor S. Automatic transmission
157Driving and parking Z

Transmission positions
B Park position
Only shift the transmission into
position
Pwhen the vehicle is sta-
tionary (Y page 172). The parking
lock should not be used as a brake when parking. Always apply the
parking brake in addition 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 into
position
Rwhen the vehicle is sta-
tionary. 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 only to posi-
tion Nif the vehicle is in danger of
skidding, 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 162)
R the position of the accelerator pedal
(Y page 161)
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 Automatic transmission
161Driving and parking Z

Problems with the transmission
Problem
Possible causes/consequences and
M
MSolutions The transmission has
problems shifting gear. The transmission is losing oil.
X Have the transmission checked at a qualified specialist work-
shop immediately. The acceleration ability
is deteriorating.
The transmission no
longer changes gear. The transmission is in emergency mode.
It is only possible to shift into
secondgear and reverse gear.
X Stop the vehicle.
X Shift the transmission to position P.
X Switch off the engine.
X Wait at least ten seconds before restarting the engine.
X Shift the transmission to position Dor R.
If D is selected, the transmission shifts into secondgear; ifRis
selected, the transmission shifts into reverse gear.
X Have the transmission checked at a qualified specialist work-
shop immediately. Refueling
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. G
WARNING
Electrostatic buildup can create sparks and
ignite fuel vapors. There is a risk of fire and
explosion.
Always touch the vehicle body before opening the fuel filler flap or touching the fuel pump
nozzle. Any existing electrostatic buildup is
thereby discharged. Refueling
167Driving and parking Z

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.
Have the brake system checked immedi-
ately. This work should be carried out at a
qualified specialist workshop.
! Vehicles with 4MATIC:
function or per-
formance tests may only be carried out on
a 2-axle dynamometer. If you are planning
to have the vehicle tested on such a dyna-
mometer, contact an authorized Mercedes-
Benz Center to obtain further information
first. Otherwise, you could damage the
drive train or the brake system.
! Vehicles with 4MATIC:
as the ESP®
sys-
tem operates automatically, the engine and
the ignition must be switched off (Smart-
Key in position 0or 1in the ignition lock or
Start/Stop button in position 0or 1) while
the parking brake is being tested on a brake
dynamometer.
Braking maneuvers triggered automatically
by ESP ®
may seriously damage the brake
system. !
Vehicles with 4MATIC:
as the ESP®
sys-
tem operates automatically, the engine and
the ignition system must be switched off
(SmartKey in position 0or 1in the ignition
lock or Start/Stop button in position 0or 1)
when:
R testing the parking brake on a brake
dynamometer.
R you intend to have the vehicle towed with
one of the axles raised.
Braking maneuvers 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. To do so, press firmly on the brake pedal when driv-
ing at a high speed. This improves the grip of
the brake pads.
You can find a description of Brake Assist
(BAS) on (Y page 71) or of BAS PLUS on
(Y page 71).
The braking characteristics of the vehicle can be seriously impaired if:
R brake pads other than those recommended
are installed
R the recommended brake fluid is not used
Safe braking can no longer be guaranteed.
AMG high-performance and ceramic
brakes The high-performance brake system is only
available on AMG vehicles.176
Driving tipsDriving and parking

The AMG brake systems are designed for
heavy loads. This may lead to noise when
braking. This will depend on:
R speed
R braking force
R environmental conditions, such as temper-
ature and humidity
The wear of individual components of the
brake system, such as the brake pads/linings or brake discs, depends on the individual driv-
ing style and operating conditions.
For this reason, it is impossible to state a
mileage that will be valid under all circum-
stances. An aggressive driving style will lead
to high wear. You can obtain further informa-
tion about this from your authorized
Mercedes-Benz Center.
New and replaced brake pads and discs only
reach their optimum braking effect after sev-
eral hundred kilometers of driving. Compen-
sate for this by applying greater force to the
brake pedal. Keep this in mind, and adapt
your driving and braking accordingly during
this break-in period.
Excessive heavy braking results in corre-
spondingly high brake wear. Observe the
brake wear warning lamp in the instrument
cluster and note any brake status messages
in the multifunction display. Especially for
high performance driving, it is important to
maintain and have the brake system checked regularly. Driving on wet roads
Hydroplaning If water has accumulated to a certain depth
on the road surface, there is a danger of
hydroplaning occurring, even if:
R
you drive at low speeds.
R the tires have adequate tread depth. For this reason, in the event of heavy rain or in
conditions in which hydroplaning may occur,
you must drive in the following manner:
R lower your speed.
R avoid ruts.
R avoid sudden steering movements.
R brake carefully.
Driving on flooded roads !
Do not drive through flooded areas.
Check the depth of any water before driving through it. Drive slowly through standing
water. Otherwise, water may enter the
vehicle interior or the engine compartment.
This can damage the electronic compo-
nents in the engine or the automatic trans- mission. Water can also be drawn in by the
engine's air suction nozzles and this can
cause engine damage. Winter driving
G
WARNING
If you shift down on a slippery road surface in an attempt to increase the engine's braking
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. G
DANGER
If the exhaust pipe is blocked or adequate
ventilation is not possible, poisonous gases
such as carbon monoxide (CO) may enter the vehicle. This is the case, e.g. if the vehicle
becomes trapped in snow. There is a risk of
fatal injury.
If you leave the engine or the auxiliary heating
running, make sure the exhaust pipe and area
around the vehicle are clear of snow. To
ensure an adequate supply of fresh air, open a window on the side of the vehicle that is not
facing into the wind. Driving tips
177Driving and parking Z

If a system malfunction occurs, the vehicle is
braked to a standstill. To drive on, depress the
accelerator again. Rear view camera
General notes Example: CLS Coupe
Rear view camera :is an optical parking and
maneuvering aid. It shows the area behind
your vehicle with guidelines in the Audio 20 or
COMAND display.
The area behind the vehicle is displayed as a
mirror image, as in the rear view mirror.
i The text shown in the Audio 20 or
COMAND display depends on the language
setting. The following are examples of rear view camera messages in the COMAND
display.
Important safety notes The rear view camera is only an aid. It is not a
replacement for your attention to your imme- diate surroundings. You are always responsi-
ble for safe maneuvering and parking. When
maneuvering or parking, make sure that there are no persons, animals or objects in the area
in which you are maneuvering.
Under the following circumstances, the rear
view camera will not function, or will function
in a limited manner:
R if the trunk lid or tailgate is open
R in heavy rain, snow or fog R
at night or in very dark places
R if the camera is exposed to very bright light
R if the area is lit by fluorescent bulbs or LED
lighting (the display may flicker)
R if there is a sudden change in temperature,
e.g. when driving into a heated garage in
winter
R if the camera lens is dirty or obstructed.
Observe the notes on cleaning
(Y page 321)
R if the rear of your vehicle is damaged. In this
event, have the camera position and setting
checked at a qualified specialist workshop
The field of vision and other functions of the
rear view camera may be restricted due to
additional accessories on the rear of the vehi-
cle (e.g. license plate holder, bicycle rack).
On vehicles with height-adjustable chassis,
leaving the standard height can result in inac- curacies in the guide lines, depending on
technical conditions.
i The rear view camera is protected from
raindrops and dust by means of a flap.
When the rear view camera is activated,
this flap opens.
The flap closes again when:
R you have finished the maneuvering proc-
ess
R you switch off the engine
R you open the trunk
Observe the notes on cleaning
(Y page 321).
For technical reasons, the flap may remain
open briefly after the rear view camera has been deactivated.
Activating/deactivating the rear view
camera X
To activate: make sure that the SmartKey
is in position 2in the ignition lock.
X Make sure that the Activation by R Activation by R
gear
gear function is selected in Audio 20 or Driving systems
205Driving and parking Z

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 26). Important safety notes
G
WARNING
If you operate information systems and com-
munication equipment integrated in the vehi- cle while driving, you will be distracted from
traffic conditions. You could also lose control of the vehicle. There is a risk of an accident.
Only operate the equipment when the traffic
situation permits. If you are not sure that this
is possible, park the vehicle paying attention
to traffic conditions and operate the equip-
ment when the vehicle is stationary.
You must observe the legal requirements for
the country in which you are currently driving when operating the on-board computer. G
WARNING
If the instrument cluster has failed or mal-
functioned, you may not recognize function
restrictions in systems relevant to safety. The operating safety of your vehicle may be
impaired. There is a risk of an accident.
Drive on carefully. Have the vehicle checked
at a qualified specialist workshop immedi-
ately.
The on-board computer only shows messages
or warnings from certain systems in the mul- tifunction display. You should therefore make sure your vehicle is operating safely at all
times.
If the operating safety of your vehicle is
impaired, pull over as soon as it is safe to do
so. Contact a qualified specialist workshop.
For an overview, see the instrument panel
illustration (Y page 33). Displays and operation
Coolant temperature display
G
WARNING
Opening the hood when the engine is over-
heated or when there is a fire in the engine
compartment could expose you to hot gases
or other service products. There is a risk of
injury.
Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department.
! A display message is shown if the coolant
temperature is too high.
If the coolant temperature is over 248 ‡
(120 †), do not continue driving. The
engine will otherwise be damaged.
The coolant temperature gauge is in the
instrument cluster on the left-hand side
(Y page 33).
Under normal operating conditions and with
the specified coolant level, the coolant tem-
perature may rise to 248 ‡ (120 †). Tachometer
! Do not drive in the overrevving range, as
this could damage the engine.
The red band in the tachometer indicates the
engine's overrevving range.
The fuel supply is interrupted to protect the
engine when the red band is reached. 226
Displays and operationOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions #
Check Brake Pad Check Brake Pad
Wear Wear The brake pads/linings have reached their wear limit.
X Visit a qualified specialist workshop. G
mbrace Inoperative mbrace Inoperative One or more main features of the mbrace system are malfunc-
tioning.
X Have the mbrace system checked at a qualified specialist work-
shop. Collision Preven‐ Collision Preven‐
tion Assist Plus tion Assist Plus
Currently Unavail‐ Currently Unavail‐
able See Opera‐ able See Opera‐
tor's Manual tor's Manual COLLISION PREVENTION ASSIST PLUS is temporarily not opera-
tional. Possible causes are:
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tions or other sources of electromagnetic radiation.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
When the causes stated above no longer apply, the display mes-
sage disappears.
COLLISION PREVENTION ASSIST PLUS is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 170).
X Restart the engine. Collision Preven‐ Collision Preven‐
tion Assist Plus tion Assist Plus
Inoperative Inoperative COLLISION PREVENTION ASSIST PLUS is temporarily inoperative
due to a malfunction. Adaptive Brake Assist may also have failed.
X Visit a qualified specialist workshop. PRE-SAFE
PRE-SAFE
Inoperative See Inoperative See
Operator's Manual Operator's Manual
Important functions of PRE-SAFE
®
have failed. All other occupant
safety systems, e.g. air bags, remain available.
X Visit a qualified specialist workshop immediately. Display
messages
249On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions Adaptive Highbeam
Adaptive Highbeam
Assist Currently Assist Currently
Unavailable See Unavailable See
Operator's Manual Operator's Manual Adaptive Highbeam Assist is deactivated and temporarily inoper-
ative. Possible causes are:
R the windshield in the camera's field of vision is dirty.
R visibility is impaired due to heavy rain, snow or fog.
X Clean the windshield.
If the system detects that the camera is fully operational again, the
Adaptive
Adaptive Highbeam
HighbeamAssist
Assistavailable
available again
againmessage is dis-
played.
Adaptive Highbeam Assist is operational again. Adaptive Highbeam Adaptive Highbeam
Assist Inoperative Assist Inoperative Adaptive Highbeam Assist is faulty.
X
Visit a qualified specialist workshop. Engine
Display messages
Possible causes/consequences and
M MSolutions +
Check Coolant Check Coolant
Level See Opera‐ Level See Opera‐
tor's Manual tor's Manual The coolant level is too low.
! Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
X Add coolant, observing the warning notes before doing so
(Y page 315).
X If coolant needs to be added more often than usual, have the
engine coolant system checked at a qualified specialist work-
shop. ? The fan motor is faulty.
X At coolant temperatures below 248 ‡ (120 †), drive to the
nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-and-go traffic. 258
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions #
Stop Vehicle See Stop Vehicle See
Operator's Manual Operator's Manual The battery is no longer being charged and the battery charge level
is too low.
A warning tone also sounds.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 170).
X Observe the instructions in the #See SeeOperator's
Operator's Manual
Manual
display message.
X Consult a qualified specialist workshop. #
Start Engine See Start Engine See
Operator's Manual Operator's Manual The engine is switched off and the battery charge level is too low.
X Switch off electrical consumers that you do not need, such as
the rear window defroster and interior lighting.
X Leave the engine running for a few minutes or drive a long dis-
tance.
The battery is being charged. 4
Check Engine Oil Check Engine Oil
At Next Refueling At Next Refueling The engine oil level has dropped to the minimum level.
A warning tone also sounds.
! Avoid long journeys with too little engine oil. The engine will
otherwise be damaged.
X Check the oil level when next refueling, at the latest
(Y page 313).
X If necessary, add engine oil (Y page 314).
X Have the engine checked at a qualified specialist workshop if
engine oil needs to be added more often than usual.
Information on approved engine oils can be obtained from any
qualified specialist workshop or on the Internet at http://
bevo.mercedes-benz.com. 4
Check Engine Oil Check Engine Oil
Level Level
(Add
(Add1
1quart)
quart) AMG vehicles: the engine oil level is too low.
!
Avoid long journeys with too little engine oil. The engine will
otherwise be damaged.
X Check the oil level when next refueling, at the latest
(Y page 313).
X If necessary, add engine oil (Y page 314).
X Have the engine checked at a qualified specialist workshop if
engine oil needs to be added more often than usual.
Information on approved engine oils can be obtained from any
qualified specialist workshop or on the Internet at http://
bevo.mercedes-benz.com. 260
Display
messagesOn-board computer and displays