2011 MERCEDES-BENZ CLS-CLASS check engine

Display messages
Possible causes/consequences and
X Solutions? Coolant
Stop
Vehicle,
turn
engine
off. The poly-V-belt could be broken.
X
Stop the vehicle immediately as soon as it is safe to do so.
X Turn off the engine immediately.
X Check the poly-V-belt.
X If it is broken: Do not continue to drive. Otherwise the
engine will overheat due to an inoperative water pump
which may result in damage to the engine. Contact an
authorized Mercedes-Benz Center.
X If it is intact: Do not continue to drive the vehicle with this
message displayed. Doing so could result in serious engine
damage that is not covered by the Mercedes-Benz Limited
Warranty.
X Observe the coolant temperature indicator in the
instrument cluster.
X Drive to the nearest authorized Mercedes-Benz Center
immediately. ? The radiator cooling fan is malfunctioning.
X
Observe the coolant temperature indicator in the
instrument cluster.
If

the coolant temperature is below 248‡ (120†), you may
continue driving to an authorized Mercedes-Benz Center.
X Avoid placing heavy loads on the engine (e.g. by driving
uphill) as well as stop-and-go traffic.
X Have the fan replaced as soon as possible. # The battery is no longer charging.
Possible causes:
R
alternator malfunctioning
R broken poly-V-belt
R a malfunction in the electronic system
X Stop immediately in a safe location or as soon as it is safe
to do so and check the poly-V-belt.
X If it is broken: Do not continue to drive. Otherwise the
engine will overheat due to an inoperative water pump
which may result in damage to the engine. Contact an
authorized Mercedes-Benz Center.
X If it is intact: Drive to the nearest authorized Mercedes-
Benz Center immediately. Adjust driving to be consistent
with reduced braking responsiveness. Vehicle status messages in the multifunction display
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Display messages
Possible causes/consequences and
X Solutions# Low
Voltage
Start
Engine The battery has insufficient voltage.
X
Start the engine. 4 Check oil
level at
next
refueling. The engine oil has dropped to a critical level.
X
Check the engine oil level ( Y page 179) and add engine oil
as required ( Y page 180).
X If you must add engine oil frequently, have the engine
checked for possible leaks. If the message
Check
oil level at next
refueling. appears while the engine is
running and at operating temperature, the
engine oil level has dropped to approximately
the minimum level.
The message will be stored in the vehicle
status message memory after you have
cleared it from the multifunction display.
Visually check for oil leaks. If there are no
obvious oil leaks, drive to the nearest service
station to refill your engine oil to the required
level. For information on approved engine oils
contact
an authorized Mercedes-Benz Center
or visit www.mbusa.com (USA only).
! Engine oil level warnings should not be
ignored. Extended driving with the symbol
displayed could result in serious engine
damage that is not covered by the
Mercedes-Benz Limited Warranty. Display messages
Possible causes/consequences and
X SolutionsC The fuel level is low.
X
Refuel at the next gas station. 7 Reserve
Fuel The fuel level has dropped below the reserve mark.
X
Refuel at the next gas station. 7 Gas Cap
Is Open A loss of pressure has been detected in the fuel system. The
fuel cap may not be closed properly or the fuel system may
be leaking.
X
Check the fuel cap ( Y page 177).
X If it is not closed properly: Close the fuel cap.
X If it is closed properly: Have the fuel system checked at
an authorized Mercedes-Benz Center. ¸ Replace
Air Filter The air filter is clogged.
X
Have the air filter checked at an authorized Mercedes-Benz
Center. 246
Vehicle status messages in the multifunction display
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Brake
Problem
Possible causes/consequences and
X Solutions!
The yellow ABS
indicator lamp
comes on while
the engine is
running. The ABS has detected a malfunction and switched off. The BAS,
the ESP
®
, the EBP, and the PRE-SAFE ®
system are also switched
off.
The brake system is still functioning normally but without the
systems specified above available.
If the ABS control unit is malfunctioning, other systems such as
the
navigation system or the automatic transmission may also be
malfunctioning.
X Continue driving with added caution. Wheels may lock during
hard braking, reducing steering capability.
X Adjust driving to be consistent with reduced braking
responsiveness.
X Read and observe messages that may appear in the
multifunction display

(Y page 228).
X Have the system checked at an authorized Mercedes-Benz
Center as soon as possible.
Failure to follow these instructions increases the risk of an
accident. !
The yellow ABS
indicator lamp
comes on while
the engine is
running. The ABS has switched off due to insufficient power supply.
The battery might not be charged sufficiently.
When the voltage is above the required value again, the ABS is
operational again. The ABS indicator lamp should go out.
X
Continue driving with added caution. Wheels may lock during
hard braking, reducing steering capability.
X Adjust driving to be consistent with reduced braking
responsiveness.
X Read and observe messages that may appear in the
multifunction display

(Y page 228).
X If the ABS indicator lamp does not go out: Have the alternator
and the battery checked. $ (USA only)
J (Canada only)
The red brake warning
lamp comes on while
driving and an acoustic
warning sounds. You are driving with the parking brake engaged.
X
Release the parking brake. 252
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Problem
Possible causes/consequences and
X Solutions$ (USA only)
J (Canada only)
The red brake warning
lamp comes on while
the engine is running
and an acoustic
warning sounds. There is insufficient brake fluid in the reservoir.
Risk of accident!
X
Do not drive any further. Stop the vehicle in a safe location as
soon as it is safe to do so.
X Engage the parking brake.
X Read and observe messages that may appear in the
multifunction display
(Y page 228).
X Contact an authorized Mercedes-Benz Center.
Do not add brake fluid! This will not solve the problem. G
Warning!
Driving with the brake warning lamp
illuminated can result in an accident. Have
your

brake system checked immediately if the
brake warning lamp stays on. Do not add
brake fluid before checking the brake system.
Overfilling the brake fluid reservoir can result
in spilling brake fluid on hot engine parts and the brake fluid catching fire. You can be
seriously burned.
! If

you find that the brake fluid in the brake
fluid reservoir has fallen to the minimum
mark or below, have the brake system
checked for brake pad thickness and leaks.
Safety systems Problem
Possible causes/consequences and
X Solutions7
The red seat belt
telltale comes
on for a
maximum of
6 seconds after
starting the
engine. The seat belt telltale reminds you and your passengers to fasten
your seat belts before driving off.
X
Fasten your seat belts.
Regardless of whether the seat belts are fastened or not, the seat
belt telltale always comes on and remains lit for 6 seconds after
starting the engine. 7
The red seat belt
telltale comes
on. In addition
you hear a
warning chime
for a maximum
of 6 seconds
after

starting the
engine. You have forgotten to fasten your seat belt.
X
Fasten your seat belt.
The warning chime stops sounding. What to do if …
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Problem
Possible causes/consequences and
X Solutions7
The red seat belt
telltale comes
on while the
vehicle is
standing still
and
the engine is
running or while
driving. You and/or your front passenger have forgotten to fasten your
seat belts.
X
Fasten your seat belts.
The seat belt telltale goes out. There are items placed on the front passenger seat and therefore
the system senses the front passenger seat as being occupied.
X
Remove the items from the front passenger seat and put them
in a safe place.
The seat belt telltale goes out. 7
The red seat belt
telltale flashes
while driving. In
addition, an
intermittent
warning chime
sounds with
increasing
intensity. The vehicle’s speed once exceeded 15 mph (25 km/h) and you
and/or your front passenger have forgotten to fasten your seat
belts.
X
Fasten your seat belts.
The seat belt telltale goes out and the warning chime stops
sounding. There are items placed on the front passenger seat and therefore
the system senses the front passenger seat as being occupied.
X
Remove the items from the front passenger seat and put them
in a safe place.
The seat belt telltale goes out and the warning chime stops
sounding. i
After
60 seconds with an unfastened seat belt the warning chime stops sounding and the
seat belt telltale illuminates continuously. The seat belt telltale will only go out if both, the
driver and front passenger’s seat belt are fastened, or the vehicle is standing still and a front
door is opened. Problem
Possible causes/consequences and
X Solutions+
The red SRS
indicator lamp
comes on while
driving. There is a malfunction in the restraint systems. The air bags or
Emergency

Tensioning Devices (ETDs) could deploy unexpectedly
or fail to activate in an accident.
X Drive with added caution to the nearest authorized Mercedes-
Benz Center. G
Warning!
In the event a malfunction of the SRS is
indicated
as outlined above, the SRS may not
be operational. For your safety, we strongly recommend that
you contact an authorized Mercedes-Benz
Center immediately to have the system
checked. Otherwise the SRS may not be
activated

when needed in an accident, which
could result in serious or fatal injury, or it 254
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might deploy unexpectedly and unnecessarily
which could also result in injury.
Problem
Possible causes/consequences and
X Solutionsd
The yellow ESP ®
warning lamp
comes on while
the engine is
running. The ESP
®
has been switched off.
Risk of accident!
When
the ESP ®
is switched off it will not stabilize the vehicle if the
system recognizes that the vehicle starts to skid or that a wheel
is spinning.
X Switch the ESP ®
back on.
Exceptions:
(Y page 60).
X If leaving the ESP ®
switched off, adapt your speed and driving
to the prevailing road and weather conditions.
X If the ESP ®
cannot be switched back on: Have the system
checked at an authorized Mercedes-Benz Center as soon as
possible. d
The yellow ESP ®
warning lamp
comes on while
the engine is
running. The ESP
®
is not operational due to a malfunction.
Risk of accident!
X Read and observe additional messages that may appear in the
multifunction display.
X Continue driving with added caution. Wheels may lock during
hard braking, reducing steering capability.
X Adapt your speed and driving to the prevailing road and weather
conditions.
X Have the system checked at an authorized Mercedes-Benz
Center as soon as possible. d
The yellow ESP ®
warning lamp
flashes while
driving. The ESP
®
or the Electronic Traction System (ETS) has come into
operation because of detected traction loss in at least one tire.
X When driving off, apply as little throttle as possible.
X While driving, ease up on the accelerator pedal.
X Adapt your speed and driving to the prevailing road and weather
conditions.
X Do not deactivate the ESP ®
.
Exceptions:
(Y page 60).
Failure to follow these instructions increases the risk of an
accident. What to do if …
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Engine
Problem
Possible causes/consequences and
X Solutions= (USA only)
; (Canada only)
The yellow engine
malfunction indicator
lamp comes on when
the engine is running. There may be a malfunction in
R
the fuel management system
R the ignition system
R the emission control system
R systems which affect emissions
Such malfunctions may result in excessive emissions values and
may
switch the engine to limp-home (emergency operation) mode.
X Have the vehicle checked as soon as possible at an authorized
Mercedes-Benz Center.
i Some states may by law require you to visit a workshop as
soon

as the engine malfunction indicator lamp comes on. Check
local requirements. = (USA only)
; (Canada only)
The yellow engine
malfunction indicator
lamp comes on when
the engine is running. A loss of pressure has been detected in the fuel system. The fuel
cap may not be closed properly or the fuel system may be leaky.
X
Check the fuel cap ( Y page 176).
X If it is not closed properly: Close the fuel cap.
X If it is closed properly: Have the fuel system checked by an
authorized Mercedes-Benz Center. ?
The red coolant
temperature
warning lamp
comes on when
the engine is
running. There is insufficient coolant in the reservoir.
If this warning lamp comes on frequently, there is a leak in the
cooling system.
If the coolant level is correct, the electric radiator fan may be
broken.
X
Immediately add coolant to prevent engine from overheating
(Y page 180).
X Have the cooling system checked.
X If the coolant temperature is below 248‡ (120†), you can
continue driving to the nearest authorized Mercedes-Benz
Center.
X Avoid high engine loads (e.g. driving uphill) and stop-and-go
driving. What to do if …
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Do not rub the battery with rags or cloths. The
battery could explode if touched due to
electrostatic charge or due to spark
formation.
! The battery is a Valve- Regulated Lead
Acid (VRLA) battery, also referred to as
“fleece” battery.
Such
batteries do not require topping-up of
the electrolyte level. VRLA batteries
therefore do not have cell caps and the
battery cover is non-removable. Do not
attempt to open the battery as otherwise
the battery will be damaged.
VRLA batteries do not require topping-up of
the electrolyte level. They cannot be
opened to check the electrolyte level.
However, the battery condition must be
checked periodically by performing a
battery conductance test. Refer to
Maintenance Booklet for battery condition
testing intervals.
The factory-equipped battery may only be
replaced with a battery that
R has the same security features
R is of identical size
R is of identical voltage
R is of identical capacity
! As any other battery, the battery may
discharge if you do not operate the vehicle
for an extended period of time. Have the
battery disconnected at a qualified
workshop or an authorized Mercedes-Benz
Center in such a case. You may also
connect an accessory battery charge unit
expressly approved by Mercedes-Benz for
your vehicle model to maintain the battery
charge. Contact an authorized Mercedes-
Benz Center for further information.
The battery, the battery ventilation hose
and the lateral plug must always be
securely installed when the vehicle is in
operation. !
Never loosen or detach battery terminal
clamps while the engine is running or the
SmartKey is in the starter switch or
KEYLESS-GO button is in position 1.
Otherwise the alternator and other
electronic components could be severely
damaged.
Have the battery checked regularly at an
authorized Mercedes-Benz Center.
Refer to Maintenance Booklet for
maintenance intervals or contact an
authorized Mercedes-Benz Center for
further information.
i After battery power was interrupted, do
the following:
R Synchronize the power windows
(Y page 95).
R Synchronize the tilt/sliding sunroof
(Y page 154). Charging the battery
G
Warning!
Never charge a battery while still installed in
the vehicle unless the accessory battery
charge unit approved by Mercedes-Benz is
being used. Gases may escape during
charging and could cause an explosion that
may

result in personal injury, paint damage or
corrosion.
An accessory battery charge unit specially
adapted for Mercedes-Benz vehicles and
tested and approved by Mercedes-Benz is
available. It permits the charging of the
battery in its installed position. Contact an
authorized Mercedes-Benz Center for
information and availability.
Charge battery in accordance with the
separate instructions for the accessory
battery charger.
Have the battery charged at an authorized
Mercedes-Benz Center. If you charge the Battery
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