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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.
Lights
i Display messages concerning LEDs:
This display message will only appear if all LEDs have failed.
Display messagesPossible causes/consequences and M Solutionsb
Check Left
Corner'g Lite
or
Right Corner'g LiteThe left or right-hand cornering light is faulty. XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Check Left Low Beam
or
Check Right Low
BeamThe left or right-hand low-beam headlamp is faulty. XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Chk. Trailer Lt
Tail Lamp
or
Chk. Trailer Rt
Tail LampThe left or right-hand trailer tail light is faulty.XCheck whether you are permitted to change the bulb yourself.
or
XVisit a qualified specialist workshop.b
Check Trailer Lt.
Turn Sig.
or
Chk. Trailer Rt
Turn Sig.The left or right-hand trailer turn signal lamp is faulty.XCheck whether you are permitted to change the bulb yourself.
or
XVisit a qualified specialist workshop.b
Chk. Trailer Brake
LampThe trailer brake lamp is faulty.XCheck whether you are permitted to change the bulb yourself.
or
XVisit a qualified specialist workshop.Display messages183On-board computer and displaysBA 204.9 USA, CA Edition A 2011; 1; 6, en-USd2mwentsVersion: 3.0.3.62010-06-15T08:58:39+02:00 - Seite 183Z
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Display messagesPossible causes/consequences and M Solutionsb
Turn Signal Rear
Left
or
Chk. Rear Rt Turn
SignalThe rear left-hand or rear right-hand turn signal is faulty.XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Chk. Front Lt.
Turn Signal
or
Front right
indicatorThe front left-hand or front right-hand turn signal is faulty.XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Check Left Mirror
Signal
or
Check Right Mirror
SignalThe turn signal in the left-hand and/or right-hand exterior mirror
is faulty.XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Chk. Center Brake
LampThe high-mounted brake lamp is faulty.XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Chk. Lt. Tail
+Brake Lmp.
or
Chk. Rt. Tail
+Brake Lmp.The left or right-hand tail lamp/brake lamp is faulty.XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Check Left High
Beam
or
Check Right High
BeamThe left or right-hand high beam is faulty. XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.184Display messagesOn-board computer and displays
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Display messagesPossible causes/consequences and M Solutionsb
Chk. Left Lic. Pl
Lamp
or
Chk. Right Lic. Pl
LampThe left or right-hand license plate lamp is faulty. XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Check Left Fog Lamp
or
Check Right Fog
LampThe left-hand or right-hand front fog lamp is faulty. XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Chk. Rear Lt. Fog
Lamp
or
Chk. Rear Rt Fog
LampThe left-hand or right-hand rear fog lamp is faulty. XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Chk. Front Lt.
Park'g Lmp
or
Chk. Front Rt.
Park'g Lmp.The front left or front right standing lamp is faulty. XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Check Left Revers.
Lmp
or
Check Right
Revers. LampThe left or right-hand backup lamp is faulty. XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Chk. Front Lt
Sidemarker
or
Chk. Front Rt
SidemarkerThe front left or right side marker lamp is faulty. XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.Display messages185On-board computer and displaysBA 204.9 USA, CA Edition A 2011; 1; 6, en-USd2mwentsVersion: 3.0.3.62010-06-15T08:58:39+02:00 - Seite 185Z
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Display messagesPossible causes/consequences and M Solutionsb
Check Rear Lt.
Sidemarker
or
Chk. Rear Rt
SidemarkerThe rear left or right side marker lamp is faulty.XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Chk. Lt. Day
Running Lite
or
Chk. Rt. Day
Running LiteThe left or right-hand daytime running lamp is defective.XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Active Headlamps
InoperativeThe active light function is faulty.XVisit a qualified specialist workshop.b
Malfunction See
Operator's ManualThe exterior lighting is faulty.XVisit a qualified specialist workshop.b
AUTO Lamps
InoperativeThe light sensor is faulty. The low-beam headlamps are switched
on.XUSA only: switch off the daytime driving lights in the on-board
computer ( Y page 172).XSwitch the lights on and off using the light switch.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.
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 234).XIf coolant needs adding more often than usual, have the engine
coolant system checked at a qualified specialist workshop.186Display messagesOn-board computer and displays
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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 as soon as possible, paying
attention to road and traffic conditions.XMake sure that the air supply to the radiator is not blocked, e.g.
by snow, slush or ice.XWait until the display message disappears before restarting the
engine. There is otherwise 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 as soon as possible, 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. There is otherwise 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.
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! 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 faulty.XAt coolant temperatures below 248 ‡ (120 †), continue driving
to the next qualified specialist workshop.XAvoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-start driving.#The battery is not being charged.
Possible causes are:
R a faulty 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
Refueling 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 233).XIf necessary, add the engine oil ( Y page 234).XHave the engine checked for leaks if engine oil has 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://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.
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Display messagesPossible causes/consequences and M SolutionsCThere is only a small amount of fuel in the fuel tank.XRefuel at the nearest gas station.8
Fuel Level LowThe fuel level has dropped into the reserve range.XRefuel at the nearest gas station.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.XIf the fuel filler cap is not correctly closed: close the fuel filler
cap.XIf the fuel filler cap is closed: visit a qualified specialist
workshop.
Driving systems
Display messagesPossible causes/consequences and M SolutionsCruise Control
InoperativeCruise control is faulty.
A warning tone also sounds.XVisit a qualified specialist workshop.Cruise Control
--- mphA condition for activating cruise control has not been met.
You attempted to save a speed of less than 20 mph (30 km/h).XIf the situation allows, drive faster than 20 mph ( 30 km/h) and
save the speed.XCheck the activation conditions for cruise control
( Y page 149).
Tires
GWarning
Do not drive with a flat tire. A flat tire affects the ability to steer or brake the vehicle. You may
lose control of the vehicle. Continued driving with a flat tire will cause excessive heat build-up
and possibly a fire.
GWarning
Follow recommended tire inflation pressures.
Do not underinflate tires. Underinflated tires wear excessively and/or unevenly, adversely affect
handling and fuel economy, and are more likely to fail from being overheated.
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Do not overinflate tires. Overinflated tires can adversely affect handling and ride comfort, wear
unevenly, increase stopping distance, and result in sudden deflation (blowout) because they are
more likely to become punctured or damaged by road debris, potholes etc.Display messagesPossible causes/consequences and M SolutionsCheck
Tire Pressure SoonGRisk of accident
The tire pressure loss warning system has detected a significant
loss in pressure.
A warning tone also sounds.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.XCheck the tires and, if necessary, change the wheel
( Y page 280).XCheck the tire pressures and, if necessary, set to the correct
tire pressure.XRestart the tire pressure loss warning system when the tire
pressure is correct ( Y page 269).Check Tire Pressure
Then Restart Run
Flat IndicatorA display message from the tire pressure loss warning system was
shown and the system has not been restarted since.XSet the correct tire pressure in all four tires.XRestart the tire pressure loss warning system ( Y page 269).Run Flat Indicator
InoperativeThe tire pressure loss warning system is faulty.XVisit a qualified specialist workshop.Tire pressures
will be displayed
after driving a
few minutesThe tire pressure monitor is measuring the tire pressure.XDrive on.
The tire pressures appear in the multifunction display after you
have been driving for a few minutes.Tire Press. Monitor
InoperativeThe TPMS is faulty.XVisit a qualified specialist workshop.Tire Pressure
Monitor
Inoperative No
Wheel SensorsThe wheels mounted do not have a suitable tire pressure sensor.
The tire pressure monitor is deactivated.XMount wheels with suitable tire pressure sensors.
The TPMS is activated automatically after driving for a few
minutes.190Display messagesOn-board computer and displays
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