2012 MERCEDES-BENZ CLS-Class C switch

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

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

Display messagesPossible causes/consequences and M Solutions¨
Pull Over Car Too
LowYou have pulled away while the vehicle level is still too low.
AIRMATIC sets the vehicle to the selected level after a short
period.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XWait until the display message disappears before pulling away.GRisk of accident
AIRMATIC is defective. A warning tone also sounds.
XDo not drive faster than 50 mph (80 km/h).XMake only slight steering movements. Otherwise, the front
fender or the tires could be damaged if the steering movement
is too large.XListen for scraping sounds.XPull over and stop the vehicle safely, paying attention to road
and traffic conditions, and select a higher vehicle level.
Depending on the malfunction, it may be possible to raise the
vehicle.XVisit a qualified specialist workshop.¨
MalfunctionGRisk of accident
The AIRMATIC function is restricted. The vehicle's handling
characteristics may be affected.
XDo not drive faster than 50 mph (80 km/h).XVisit a qualified specialist workshop.HOLD
OffThe HOLD function is deactivated. The vehicle is skidding.
A warning tone also sounds.XReactivate the HOLD function later ( Y page 166).Radar Sensors
Deactivated See
Operator's ManualThe radar sensor system is deactivated.XSwitch on the radar sensor system ( Y page 211).230Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M SolutionsBlind Spot Assist
Inoperative or
Active Blind Spot
Assist InoperativeBlind Spot Assist or Active Blind Spot Assist is defective.
The yellow 9 indicator lamps also light up in the exterior
mirrors.XVisit a qualified specialist workshop.Park Assist
CanceledThe driver's door is open and the driver's seat belt has not been
fastened.XRepeat the parking process with the seat belt fastened and the
driver's door closed.You have inadvertently touched the multifunction steering wheel
while steering intervention was active.XWhile steering intervention is active, make sure that the
multifunction steering wheel is not touched.The vehicle has started to skid and ESP ®
has intervened.XUse Active Parking Assist again later ( Y page 175).Park Assist
InoperativeYou have just performed a large number of turning or parking
maneuvers.
Active Parking Assist will become available again after
approximately 10 minutes ( Y page 175).XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XSwitch off and restart the engine.XIf the warning message does not disappear: consult a qualified
specialist workshop.PARKTRONIC is defective.XVisit a qualified specialist workshop.Park Assist
FinishedThe vehicle is parked. A warning tone also sounds.
The display message disappears automatically.DISTRONIC PLUS
OffDISTRONIC PLUS has been deactivated ( Y page 157). If it was
deactivated automatically, a warning tone also sounds.DISTRONIC PLUS
Now AvailableDISTRONIC PLUS is operational again after having been
temporarily unavailable. You can now reactivate DISTRONIC PLUS
( Y page 157).232Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M SolutionsD
Power Steering
Malfunction See
Operator's ManualGRisk of accident
The power steering assistance is defective.
You will need to use more force to steer.
A warning tone also sounds.
XCheck whether you are able to apply the extra force required.XIf you are able to steer safely: carefully drive on to a qualified
specialist workshop.XIf you are unable to steer safely: do not drive on. Contact the
nearest qualified specialist workshop.¥
Check Washer FluidThe washer fluid level in the washer fluid reservoir has dropped
below the minimum.XAdd washer fluid ( Y page 283).
SmartKey
Display messagesPossible causes/consequences and M SolutionsÂ
Key Does Not
Belong to VehicleYou have put the wrong SmartKey in the ignition lock.XUse the correct SmartKey.Â
Take Your Key from
IgnitionThe SmartKey is in the ignition lock.XRemove the SmartKey.Â
Obtain a New KeyThe SmartKey needs to be replaced.XVisit a qualified specialist workshop.Â
Replace Key BatteryThe batteries of the KEYLESS-GO key are discharged.XChange the batteries ( Y page 76).Â
Don't Forget Your
KeyThe display message is shown for a maximum of 60 seconds and
is only a reminder.
You have opened the driver's door with the engine switched off.
The KEYLESS-GO key is not in the ignition lock.XRemember to take the KEYLESS-GO key with you when you
leave the vehicle.Display messages239On-board computer and displaysZ

Display messagesPossible causes/consequences and M SolutionsÂ
Key Not Detected
(Red display message)The KEYLESS-GO key is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle
centrally or start the engine.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XLocate the KEYLESS-GO key.The KEYLESS-GO key is not detected while the engine is running
because there is interference from a strong source of radio waves.
A warning tone also sounds.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XOperate the vehicle with the SmartKey in the ignition lock.Â
Key Not Detected
(White display
message)The KEYLESS-GO key cannot be detected at present.XChange the location of the key with the KEYLESS-GO functions
in the vehicle.
If the KEYLESS-GO key is still not detected:
XChange the location of the key with the KEYLESS-GO functions
in the vehicle.XOperate the vehicle with the SmartKey in the ignition lock.Â
Key still in
vehicleThe KEYLESS-GO key has been detected inside the vehicle during
locking.XRemove the KEYLESS-GO key from the vehicle.Â
Remove 'Start'
Button and Insert
KeyKEYLESS-GO is temporarily malfunctioning or is defective. A
warning tone also sounds.XInsert the SmartKey into the ignition lock and turn it to the
desired position.XVisit a qualified specialist workshop.Â
Close Doors to
Lock VehicleAt least one door is open. A warning tone also sounds.XClose all doors and lock the vehicle again.240Display messagesOn-board computer and displays