MERCEDES-BENZ E-Class CABRIOLET 2012 C207 Owner's Manual
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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 messages219On-board computer and displaysZ 
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Display messagesPossible causes/consequences and M SolutionsFront Passenger 
Airbag Enabled
See Operator's 
ManualThe front-passenger air bag is enabled during the journey, even
though:
R a child, a small adult or an object weighing less than the
system's weight threshold is located on the front-passenger
seat.
R the front-passenger seat is unoccupied.
The system may detect objects or forces applying additional
weight on the seat.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.XOpen the front-passenger door.XRemove the child and the child restraint system from the front-
passenger seat.XIf necessary, secure the child in a child restraint system on a
suitable rear seat.XMake sure that there are no objects on the seat adding to the
weight.
The system may otherwise detect the additional weight and
interpret the seat occupant's weight as greater than it actually
is.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.
R the  Front Passenger Airbag Enabled See Operator's 
Manual  or Front Passenger Airbag Disabl'd 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 fulfilled, 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 fulfilled, the system is not operating
correctly.
220Display messagesOn-board computer and displays 
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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 Disabl'd
See Operator's 
ManualThe front-passenger air bag is 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.
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 fulfilled, 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 fulfilled, the system is not operating
correctly.
XVisit a qualified specialist workshop immediately.Display messages221On-board computer and displaysZ 
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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 orCheck Right 
Cornering LightThe left or right-hand cornering light is defective.XCheck whether you are permitted to change the bulb yourself
( Y  page 122).
or
XVisit a qualified specialist workshop.b
Check Left Low 
Beam orCheck Right 
Low BeamThe left or right-hand low-beam headlamp is defective.XCheck whether you are permitted to change the bulb yourself
( Y  page 122).
or
XVisit a qualified specialist workshop.b
Check Rear Left 
Turn Signal orCheck 
Rear Right Turn 
SignalThe rear left-hand or rear right-hand turn signal is defective.XCheck whether you are permitted to change the bulb yourself
( Y  page 122).
or
XVisit a qualified specialist workshop.b
Check Front Left 
Turn Signal orCheck 
Front Right Turn 
SignalThe front left-hand or front right-hand turn signal is defective.XCheck whether you are permitted to change the bulb yourself
( Y  page 122).
or
XVisit a qualified specialist workshop.b
Check Left Mirror 
Turn Signal orCheck 
Right Mirror Turn 
SignalThe turn signal in the left-hand or right-hand exterior mirror is
defective.XCheck whether you are permitted to change the bulb yourself
( Y  page 122).
or
XVisit a qualified specialist workshop.222Display messagesOn-board computer and displays 
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Display messagesPossible causes/consequences and M Solutionsb
Check Center Brake 
LampThe high-mounted brake lamp is faulty.XCheck whether you are permitted to change the bulb yourself
( Y  page 122).
or
XVisit a qualified specialist workshop.b
Check Left Tail 
and Brake 
Lamps orCheck Right 
Tail and Brake 
LampsThe left or right-hand tail lamp/brake lamp is defective.XCheck whether you are permitted to change the bulb yourself
( Y  page 122).
or
XVisit a qualified specialist workshop.b
Check Left High 
Beam orCheck Right 
High BeamThe left or right-hand high beam is defective.XCheck whether you are permitted to change the bulb yourself
( Y  page 122).
or
XVisit a qualified specialist workshop.b
Check Left License 
Plate Lamp orCheck 
Right License 
Plate LampThe left or right-hand license plate lamp is defective.XCheck whether you are permitted to change the bulb yourself
( Y  page 122).
or
XVisit a qualified specialist workshop.b
Check Left Fog 
Lamp orCheck Right 
Fog LampThe left-hand or right-hand front fog lamp is defective.XCheck whether you are permitted to change the bulb yourself
( Y  page 122).
or
XVisit a qualified specialist workshop.b
Rear Fog LampThe rear fog lamp is defective.XCheck whether you are permitted to change the bulb yourself
( Y  page 122).
or
XVisit a qualified specialist workshop.Display messages223On-board computer and displaysZ 
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Display messagesPossible causes/consequences and M Solutionsb
Check Front Left 
Parking 
Lamp orCheck Front 
Right Parking LampThe front left or front right parking or standing lamp is defective.XCheck whether you are permitted to change the bulb yourself
( Y  page 122).
or
XVisit a qualified specialist workshop.b
Check Left Reverse 
Lamp orCheck Right 
Reverse LampThe left or right-hand backup lamp is defective.XCheck whether you are permitted to change the bulb yourself
( Y  page 122).
or
XVisit a qualified specialist workshop.b
Check Front Left 
Sidemarker 
Lamp orCheck Front 
Right Sidemarker 
LampThe left or right front side marker lamp is defective.XCheck whether you are permitted to change the bulb yourself
( Y  page 122).
or
XVisit a qualified specialist workshop.b
Check Rear Left 
Sidemarker 
Lamp orCheck Rear 
Right Sidemarker 
LampThe rear left or right side marker lamp is defective.XCheck whether you are permitted to change the bulb yourself
( Y  page 122).
or
XVisit a qualified specialist workshop.b
Check Left Daytime 
Running 
Light orCheck Right 
Daytime Running 
LightThe left or right-hand daytime running lamp is defective.XCheck whether you are permitted to change the bulb yourself
( Y  page 122).
or
XVisit a qualified specialist workshop.b
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.224Display messagesOn-board computer and displays 
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Display messagesPossible causes/consequences and M Solutionsb
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  c or à .Adaptive Highbeam 
Assist InoperativeAdaptive Highbeam Assist is faulty.XVisit a qualified specialist workshop.Adaptive Highbeam 
Assist Currently 
Unavailable See 
Operator's ManualAdaptive Highbeam Assist is deactivated and temporarily
inoperative. 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.XClean the windshield.
If the system detects that the camera is fully functional again, the
Adaptive Highbeam Assist Now Available  display message
is shown.
Adaptive Highbeam Assist is operational again.
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 276).XIf coolant needs to be added more often than usual, have the
engine coolant system checked at a qualified specialist
workshop.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 messages225On-board computer and displaysZ 
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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 not damaged:
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.
!  If the coolant temperature exceeds 248  ‡(120  †) do not continue driving. The engine will
otherwise be damaged.
226Display messagesOn-board computer and displays 
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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 not damaged:
XVisit a qualified specialist workshop.4
Check Engine Oil 
At Next RefuelingThe engine oil level has dropped to the minimum level.
A warning tone also sounds.XCheck the engine oil level at the latest when next refueling
( Y  page 275).XIf necessary, add engine oil ( Y page 275).XIf engine oil needs to be added more often than usual, have the
engine checked at a qualified specialist workshop.
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.
Display messages227On-board computer and displaysZ 
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Display messagesPossible causes/consequences and M Solutions8
Fuel Level LowThe fuel level has dropped into the reserve range.XRefuel at the nearest gas station.CThere is only a very small amount of fuel in the fuel tank.XRefuel at the nearest gas station without fail.8
Gas Cap LooseThe fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.XCheck that the fuel filler cap is correctly closed.
If the fuel filler cap is not correctly closed:
XClose the fuel filler cap.
If the fuel filler cap is correctly closed:
XVisit a qualified specialist workshop.
Driving systems
Display messagesPossible causes/consequences and  M SolutionsÀ
Attention Assist: 
Pause!Based on specific criteria, ATTENTION ASSIST has determined that
the driver is tired or paying less attention. A warning tone also
sounds.XIf necessary, take a break.
During long journeys, take regular breaks in good time so you get
enough rest.
À
Attention Assist 
InoperativeATTENTION ASSIST has failed.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 176).The HOLD function is deactivated. When the brake pedal is firmly
depressed, an activation condition is not fulfilled.
A warning tone also sounds.XCheck the activation conditions for the HOLD function
( Y  page 176).228Display messagesOn-board computer and displays