warning MERCEDES-BENZ CLS 2012 Owners Manual

Display messages
General information
GWARNING
All categories of messages contain important information which should be taken note of and,
where a malfunction is indicated, addressed as soon as possible at an authorized Mercedes-Benz
Center.
Failure to repair the condition noted may cause damage not covered by the Mercedes-Benz
Limited Warranty, or result in property damage or personal injury.
Display messages appear in the multifunction display.
Display messages with graphic displays may be shown in simplified form in the Operator's
Manual and may differ from the messages shown in the multifunction display.
Please respond in accordance with the display messages and follow the additional notes in
this Operator's Manual.
Certain display messages are accompanied by an audible warning tone or a continuous tone.
When you stop and park the vehicle, please observe the notes on the HOLD function
( Y page 166) and parking ( Y page 150).
Hiding display messages
You can hide some display messages with a low priority.
XPress the a or % button on the steering wheel to hide the display message.
The display message is cleared.
Display messages with a high priority are shown in red.
You cannot hide display messages of the highest priority. The multifunction display shows
these messages continuously until the causes for the messages have been remedied.
Message memory
The on-board computer saves certain display messages. You can call up the display messages
in the message memory .
XPress the = or ; button on the steering wheel to select the Serv. menu.
If there are display messages, the multifunction display shows, for example, 2 Messages.XPress the 9 or : button to select the entry, e.g. 2 Messages.XConfirm with a.XPress the 9 or : button to scroll through the display messages.
When the ignition is switched off, all display messages are deleted apart from some high-
priority display messages. Once the causes of the high-priority display messages have been
rectified, the corresponding display messages are also deleted.
216Display messagesOn-board computer and displays

Safety systemsDisplay messagesPossible causes/consequences and M Solutions!÷
Currently
Unavailable See
Operator's ManualGRisk of accident
ABS (Anti-lock Braking System), ESP ®
(Electronic Stability
Program), BAS (Brake Assist), PRE-SAFE ®
, the HOLD function and
hill start assist are temporarily unavailable.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster.
The self-diagnosis function might not be complete, for example.
ATTENTION ASSIST is deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XCarefully drive a suitable distance making slight steering
movements at a speed above 12 mph (20 km/h).
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
XDrive on carefully.XVisit a qualified specialist workshop.GRisk of accident
ABS, ESP ®
, BAS, PRE-SAFE ®
, the HOLD function and hill start
assist are temporarily unavailable.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster.
For example, the on-board voltage may be insufficient.
ATTENTION ASSIST is deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XDrive on carefully.
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
XDrive on carefully.XVisit a qualified specialist workshop.Display messages217On-board computer and displaysZ

Display messagesPossible causes/consequences and M Solutions!÷
Inoperative See
Operator's ManualGRisk of accident
ABS, ESP ®
, BAS, PRE-SAFE ®
, the HOLD function and hill start
assist are not available due to a malfunction.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
The $ (USA only)/ J (Canada only), ÷, å and !
warning lamps in the instrument cluster also light up.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
ATTENTION ASSIST is deactivated.
XDrive on carefully.XVisit a qualified specialist workshop immediately.÷
Inoperative See
Operator's ManualGRisk of accident
ESP ®
, BAS, PRE-SAFE ®
, the HOLD function and hill start assist are
not available due to a malfunction.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷ and å warning lamps light up in the
instrument cluster.
ATTENTION ASSIST is deactivated.
The brake system continues to function normally, but without the
functions listed above.
XDrive on carefully.XVisit a qualified specialist workshop.T !
÷
Inoperative See
Operator's ManualGRisk of accident
EBD (electronic brake force distribution), ABS, ESP ®
, BAS, PRE-
SAFE ®
, the HOLD function and hill start assist are not available
due to a malfunction.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷, å and ! warning lamps light up in
the instrument cluster and a warning tone sounds.
ATTENTION ASSIST is deactivated.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
XDrive on carefully.XVisit a qualified specialist workshop immediately.218Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M Solutions#
Check Brake Pad
WearThe brake pads/linings have reached their wear limit.XVisit a qualified specialist workshop.$ (USA
only) J (Canada
only)
Release Parking
BrakeYou are driving with the parking brake applied. A warning tone also
sounds.XRelease the parking brake$ (USA
only) J (Canada
only)
Check Brake Fluid
LevelGRisk of accident
There is not enough brake fluid in the brake fluid reservoir.
Additionally, the red $ (USA only)/ J (Canada only)
warning lamp lights up in the instrument cluster and a warning
tone sounds.
XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.XEngage the parking brake.XConsult a qualified specialist workshop.XDo not add brake fluid. This will not correct the malfunction.GWARNING
Driving with the message Check Brake Fluid Level displayed can result in an accident. Have
your brake system checked immediately.
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.
Display messages219On-board computer and displaysZ

Display messagesPossible causes/consequences and M SolutionsPRE-SAFE
Functions Limited
See Operator's
ManualGRisk of accident
PRE-SAFE ®
Brake is defective. BAS PLUS or the distance warning
signal may also have failed.
XVisit a qualified specialist workshop.6
SRS Malfunction
Service RequiredGRisk of injury
There is a malfunction in the SRS (Supplemental Restraint
System). The 6 warning lamp also lights up in the instrument
cluster.
XVisit a qualified specialist workshop.6
Front Left
Malfunction
Service Required or
Front Right
Malfunction
Service RequiredGRisk of injury
SRS has malfunctioned at the front on the left or right. The 6
warning lamp also lights up in the instrument cluster.
XVisit a qualified specialist workshop.6
Rear Left
Malfunction
Service Required or
Rear Right
Malfunction
Service RequiredGRisk of injury
SRS has malfunctioned at the rear on the left or right. The 6
warning lamp also lights up in the instrument cluster.
XVisit a qualified specialist workshop.6
Left Side Curtain
Airbag Malfunction
Service Required or
Right Side Curtain
Airbag Malfunction
Service RequiredGRisk of injury
There is a malfunction in the left-hand and/or right-hand window
curtain air bag. The 6 warning lamp also lights up in the
instrument cluster.
XVisit a qualified specialist workshop.GWARNING
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 might deploy unexpectedly and
unnecessarily which could also result in injury.
Display messages221On-board computer and displaysZ

Display messagesPossible causes/consequences and M SolutionsXVisit a qualified specialist workshop immediately.GWARNING
If the 45 indicator lamp remains off even after performing the above corrective steps, do
not have any children 12 years old and under and other small individuals use the front-passenger
seat until the system has been repaired.
Display messagesPossible causes/consequences and M SolutionsFront Passenger
Airbag Disabled
See Operator's
ManualThe front-passenger air bag and the front-passenger knee bag are
deactivated during the journey even though an adult or a person
larger than a certain size is occupying the front-passenger seat. If
additional forces are applied to the seat, the system may interpret
the occupant's weight as lower than it actually is.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XSwitch off the ignition.XHave the occupant get out of the vehicle.XKeep the seat unoccupied, close the front-passenger door and
switch on the ignition.
Observe the 45(Y page 43) indicator lamp and the
multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the 45 indicator lamp must light up and remain lit. When
the indicator lamp is on, OCS ( Y page 43) has deactivated the
front-passenger air bag and front-passenger knee bag.
R the Front Passenger Airbag Enabled See Operator's
Manual or Front Passenger Airbag Disabled See
Operator's Manual display messages must not appear in the
multifunction display. Wait for a period of at least 60 seconds
until the necessary system checks have been completed and to
make sure that the display messages do not appear in the
multifunction display.
If these conditions are met, the front-passenger seat can be
occupied again. Whether the 45 indicator lamp remains lit
or goes out depends on how OCS classifies the occupant.
If the conditions are not met, the system is not operating correctly.
XVisit a qualified specialist workshop immediately.Display messages223On-board computer and displaysZ

GWARNING
If the 45 indicator lamp remains lit with an adult occupant on the front-passenger seat
even after performing the above corrective steps, do not have any passenger use the front-
passenger seat until the system has been repaired.
Lights
i Display messages about LEDs:
This display message will only appear if all LEDs have failed.
Display messagesPossible causes/consequences and M Solutionsb
Check Left
Cornering Light
or Check Right
Cornering LightThe left or right-hand cornering light is defective.XVisit a qualified specialist workshop.b
Check Left Low
Beam or Check Right
Low BeamThe left or right-hand low-beam headlamp is defective.XVisit a qualified specialist workshop.b
Check Rear Left
Turn Signal
or Check Rear Right
Turn SignalThe rear left-hand or rear right-hand turn signal is defective.XVisit a qualified specialist workshop.b
Check Front Left
Turn Signal
or Check Front
Right Turn SignalThe front left-hand or front right-hand turn signal is defective.XVisit a qualified specialist workshop.b
Check Left Mirror
Turn Signal
or Check Right
Mirror Turn SignalThe turn signal in the left-hand or right-hand exterior mirror is
defective.XVisit a qualified specialist workshop.b
Check Center Brake
LampThe high-mounted brake lamp is faulty.XVisit a qualified specialist workshop.224Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M Solutionsb
Active Headlamps
InoperativeThe active light function is defective.XVisit a qualified specialist workshop.b
Malfunction See
Operator's ManualThe exterior lighting is defective.XVisit a qualified specialist workshop.b
AUTO Lamp Function
InoperativeThe light sensor is defective.XVisit a qualified specialist workshop.b
Switch Off LightsThe lights are still switched on when you leave the vehicle. A
warning tone also sounds.XTurn the light switch to Ã.Adaptive Highbeam
Assist InoperativeAdaptive Highbeam Assist is defective.XVisit a qualified specialist workshop.Adaptive Highbeam
Assist Currently
Unavailable See
Operator's ManualAdaptive Highbeam Assist is deactivated and temporarily
inoperative, if:
R the windshield is dirty in the camera's field of vision.
R visibility is impaired due to heavy rain, snow or fog.XClean the windshield.
Adaptive Highbeam Assist is available again, if:
R the dirt (e.g. slush) drops away while the vehicle is in motion.
R the system recognizes that the camera is fully operational again.
The Adaptive Highbeam Assist Now Available message is
displayed.
Engine
Display messagesPossible causes/consequences and M Solutions+
Check Coolant
Level See
Operator's ManualThe coolant level is too low.XAdd coolant, observing the warning notes when doing so
( Y page 282).XIf the coolant needs to be refilled more often than usual, have
the engine coolant system checked at a qualified specialist
workshop.226Display messagesOn-board computer and displays

GWARNING
Do not spill antifreeze on hot engine parts. Antifreeze contains ethylene glycol which may burn
if it comes into contact with hot engine parts. You could be seriously burned.
! The coolant level is too low. Avoid making long journeys with too little coolant in the cooling
system. The engine will otherwise be damaged.
The display messages and the corresponding symbol that indicate that the coolant level is
too low must not be ignored.
Display messagesPossible causes/consequences and M Solutions?
Coolant Level Low
Stop Vehicle Turn
Engine OffThe coolant is too hot.XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XMake sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.XWait until the display message disappears before restarting the
engine. Otherwise, there is a risk of engine damage.XPay attention to the coolant temperature display.XIf the temperature increases again, visit a qualified specialist
workshop immediately.The poly-V-belt may have torn.XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XOpen the hood.XCheck whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do not continue driving. The engine could otherwise overheat.
XConsult a qualified specialist workshop.
If the poly-V-belt is OK:
XWait until the display message disappears before restarting the
engine. Otherwise, there is a risk of engine damage.XPay attention to the coolant temperature display.XVisit a qualified specialist workshop.GWARNING
Driving when your engine is overheated can cause some fluids which may have leaked into the
engine compartment to catch fire. You could be seriously burned.
Steam from an overheated engine can cause serious burns which can occur just by opening the
engine hood. Stay away from the engine if you see or hear steam coming from it.
Stop the vehicle in a safe location away from other traffic. Turn off the engine, get out of the
vehicle and do not stand near the vehicle until the engine has cooled down.
Display messages227On-board computer and displaysZ

! If the coolant temperature exceeds 248 ‡(120 †) do not continue driving. The engine will
otherwise be damaged.Display messagesPossible causes/consequences and M Solutions?The engine fan is defective.XAt coolant temperatures under 248 ‡ (120 †), drive to the next
qualified specialist workshop.XAvoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic.#The battery is not being charged.
Possible causes are:
R a defective alternator
R a torn poly-V-belt
R a malfunction in the electronicsXPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XOpen the hood.XCheck whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do not continue driving. The engine could otherwise overheat.
XConsult a qualified specialist workshop.
If the poly-V-belt is OK:
XVisit a qualified specialist workshop.4
Check Engine Oil
At Next RefuelingThe engine oil level has dropped to a critical level.
A warning tone also sounds.XCheck the oil level ( Y page 281).XIf necessary, add engine oil ( Y page 282).XHave the engine checked for leaks if the engine oil needs to be
refilled more often than usual.
Information on approved engine oils can be obtained from any qualified specialist workshop
or on the Internet at http://www.mbusa.com (USA only).
! The oil level is too low. Avoid long journeys with too little engine oil. There is a risk of
engine damage.
The display messages and the corresponding symbol that indicate that the oil level is too
low must not be ignored.
228Display messagesOn-board computer and displays