Page 369 of 494

Display messages Possible causes/consequences and
M Solutions
lamp remains lit or goes out depends on how OCS classifies the
occupant.
If the conditions are no
tfulfilled, the system is no toperating
correctly.
X Visit a qualified specialist workshop immediately. G
WARNING
If the 42 indicator lamp remains off even after performing the above corrective
steps, do not have any children twelve years old and under and other small individuals 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 messages Possible causes/consequences and
M Solutions
b
Check Left
Cornering
Light or
Check Right Cornering
Light The left or right-hand cornering light is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 256).
or
X Visit a qualified specialist workshop. b
Check Left Low
Beam or
Check Right
Low Beam The left or right-hand low-beam headlamp is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 256).
or
X Visit a qualified specialist workshop. b
Check Rear Left
Turn
Signal or
Check Rear Right Turn
Signal The rear left-hand or rear right-hand turn signal is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 256).
or
X Visit a qualified specialist workshop. Display messages
367On-board computer and displays Z
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Display messages Possible causes/consequences and
M Solutions
b
Check Front Left
Turn
Signal or
Check Front Right Turn
Signal The front left-hand or front right-hand turn signal is defective.
X
Chec kwhether you are permitted to change the bulb yourself
(Y page 256).
or
X Visit a qualified specialist workshop. b
Check Left Mirror
Turn
Signal or
Check Right Mirror Turn
Signal The turn signal in the left-hand or right-hand exterior mirror is
defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 256).
or
X Visit a qualified specialist workshop. b
Check
Center Brake
Lamp The high-mounted brake lamp is faulty.
X
Check whether you are permitted to change the bulb yourself
(Y page 256).
or
X Visit a qualified specialist workshop. b
Check Left Tail
and Brake
Lamp or
Check Right
Tail and Brake Lamp The left or right-hand tail lamp/brake lamp is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 256).
or
X Visit a qualified specialist workshop. b
Check Left High
Beam or
Check Right
High Beam The left or right-hand high beam is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 256).
or
X Visit a qualified specialist workshop. b
Check
Left License
Plate Lamp or
Check Right License
Plate Lamp The left or right-hand license plate lamp is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 256).
or
X Visit a qualified specialist workshop. 368
Display messagesOn-board computer and displays
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Display messages Possible causes/consequences and
M Solutions
b
Check Left Fog
Lamp or
Check Right
Fog Lamp The left-hand or right-hand fron
tfog lamp is defective.
X Check whether you are permitted to change the bulb yourself
(Y page 256).
or
X Visit a qualified specialist workshop. b
Check Rear Left
Fog Lamp or
Check Rear Right Fog Lamp The left-hand or right-hand rear fog lamp is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 256).
or
X Visit a qualified specialist workshop. b
Check Front Left
Parking
Lamp or
Check Front
Right Parking Lamp The front left or front right parking or standing lamp is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 256).
or
X Visit a qualified specialist workshop. b
Check
Left Reverse
Lamp or
Check Right
Reverse Lamp The left or right-hand backup lamp is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 256).
or
X Visit a qualified specialist workshop. b
Check Front Left
Sidemarker
Lamp or
Check Front
Right Sidemarker
Lamp The left or right front side marker lamp is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 256).
or
X Visit a qualified specialist workshop. b
Check Rear Left
Sidemarker
Lamp or
Check Rear Right Sidemarker
Lamp The rear left or right side marker lamp is defective.
X
Check whether you are permitted to change the bulb yourself
(Y page 256).
or
X Visit a qualified specialist workshop. Display messages
369On-board computer and displays Z
Page 372 of 494

Display messages Possible causes/consequences and
M Solutions
b
Check
Left Daytime
Running
Light or
Check Right Daytime
Running Light The lef
torright-hand daytime running lamp is defective.
X Check whether you are permitted to change the bulb yourself
(Y page 256).
or
X Visit a qualified specialist workshop. b
Active Headlamps
Inoperative The active light function is defective.
X
Visit a qualified specialist workshop. b
Malfunction See
Oper. Manual The exterior lighting is defective.
X
Visit a qualified specialist workshop. b
AUTO
Lamp Function
Inoperative The light sensor is defective.
X
Visit a qualified specialist workshop.
USA only:
X Switch off the daytime running lamps in the on-board computer
(Y page 349).
X Switch the lights on and off using the light switch. b
Please Switch Off
Lights The lights are still switched on when you leave the vehicle. A
warning tone also sounds.
X
Turn the light switch to $orc.
or
X If the rear fog lamp is switched on: press the light switch in to
the stop. Adaptive High-beam
Assist Inoperative Adaptive Highbeam Assist is faulty.
X
Visit a qualified specialist workshop. 370
Display messagesOn-board computer and displays
Page 373 of 494
Engine
Display messages Possible causes/consequences and
M Solutions
+
Check Coolant
Level See Oper.
Manual The coolant level is too low.
!
Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
X Add coolant, observing the warning notes before doing so
(Y page 424).
X If coolant needs to be added more often than usual, have the
engine coolant system checked at a qualified specialist
workshop. Displa
ymessages
371On-board computer and displays Z
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Display messages Possible causes/consequences and
M Solutions
? The fan motor is faulty.
X
At coolan ttemperatures under 248 ‡(120 †), drive to the next
qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic. ?
Coolant Low Stop
Vehicle Turn
Engine Off The coolant is too hot.
Aw
arning tone also sounds.
G WARNING
Do no tdrive when youre ngine is overheated. Thi scan cause some
fluids which may have leaked into the engine compartmen tto
catch fire.
Stea mfrom the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 289).
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Do not start the engine again until the display message goes out
and the coolant temperature is under 248 ‡ (120 †).
Otherwise, the engine could be damaged.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 248 ‡ (120 †). 372
Display messagesOn-board computer and displays
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Display messages Possible causes/consequences and
M Solutions
# The battery is no
tbeing charged.
Possible causes are:
R a defective alternator
R a torn poly-V-belt
R a malfunction in the electronics
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Open the hood.
X Check whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do not continue driving. The engine could otherwise overheat.
X Consult a qualified specialist workshop.
If the poly-V-belt is not damaged:
X Visit a qualified specialist workshop. 4
Check Engine Oil
at Next Refueling Vehicles with an oil dipstick
:the oil level has dropped to the
minimum level.
X Check the oil level when next refueling, at the latest
(Y page 421).
X If necessary, add engine oil (Y page 423).
X Have the engine checked at a qualified specialist workshop if
engine oil needs to be added more often than usual.
! Avoid long journeys with too little engine oil. The engine will
otherwise be damaged.
Information on approved engine oils can be obtained from any
qualified specialist workshop or on the Internet at http://
www.mbusa.com (USA only). 4
Check Engine Oil
Level (Add 1
quart) (USA only)
Check Engine Oil Level (Add 1
Liter) (Canada only) Vehicles without an oil dipstick: the engine oil level is too low.
X
Check the oil level when next refueling, at the latest
(Y page 421).
X If necessary, add engine oil (Y page 423).
X Have the engine checked at a qualified specialist workshop if
engine oil needs to be added more often than usual.
! Avoid long journeys with too little engine oil. The engine will
otherwise be damaged.
Information on approved engine oils can be obtained from any
qualified specialist workshop or on the Internet at http://
www.mbusa.com (USA only). Display messages
373On-board computer and displays Z
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Display messages Possible causes/consequences and
M Solutions
4
Engine Oil Level
Low Stop Vehicle
Turn Engine Off Vehicles without an oil dipstick
:the engine oil level is too low.
There is a risk of engine damage.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Apply the parking brake.
X Add engine oil (Y page 423) and check the oil level
(Y page 421). 4
Engine Oil Level
Too High Vehicles without an oil dipstick: you have added too much engine
oil. There is a risk of damage to the engine or to the catalytic
converter.
X
Have the excess oil siphoned off at a qualified specialist
workshop. Observe the legal requirements. 4
Engine Oil Level
Cannot measure
eng. oil level Vehicles without an oil dipstick: the measuring system is
defective.
X
Visit a qualified specialist workshop. 8
Reserve fuel level The fuel level has dropped into the reserve range.
X
Refuel at the nearest gas station. C There is only a very small amount of fuel in the fuel tank.
X
Refuel at the nearest gas station without fail. 8
Fuel filler cap
open The fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.
X
Check that the fuel filler cap is correctly closed.
If the fuel filler cap is not correctly closed:
X Close the fuel filler cap.
If the fuel filler cap is correctly closed:
X Visit a qualified specialist workshop. 374
Display messagesOn-board computer and displays