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329 Practical hints
What to do if …?
During severe operating conditions and
stop-and-go city traffic, the coolant tem-
perature may rise close to 248°F (120°C).
Display symbol
Display message
Possible cause
Possible solution
Ï
Coolant
Stop, engine off!
The coolant is too hot.
Stop the vehicle and turn off the en-
gine.
Only start the engine again after the
message disappears. You could other-
wise damage the engine.
Warning!
G
Driving when your engine is badly overheat-
ed 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 and can occur just by opening
the hood. Stay away from the engine if you
see or hear steam coming from it.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until the
engine has cooled down.
!The engine should not be operated with
the coolant temperature above 248°F
(120°C). Doing so may cause serious
engine damage which is not covered by
the Mercedes-Benz Limited Warranty.
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Page 330 of 464
330 Practical hintsWhat to do if …?Display symbol
Display message
Possible cause
Possible solution
Ï
Coolant
Stop, engine off!
The poly-V-belt could be broken.
Stop immediately and check the
poly-V-belt.
If it is broken:
Do not continue to drive. Otherwise
the engine will overheat due to an in-
operative water pump which may re-
sult in damage to the engine. Notify an
authorized Mercedes-Benz Center.
If it is intact:
Do not continue to drive the vehicle
with this message displayed. Doing so
could result in serious engine damage
that is not covered by the
Mercedes-Benz Limited Warranty.
Coolant
Visit workshop
The cooling fan for the coolant is malfunc-
tioning.
Observe the coolant temperature dis-
play.
Have the fan replaced as soon as pos-
sible.
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Page 331 of 464
331 Practical hints
What to do if …?
Display symbol
Display message
Possible cause
Possible solution
G
Display defective
Visit workshop!
The instrument cluster display is malfunc-
tioning.
Continue driving with added caution.
Visit an authorized Mercedes-Benz
Center as soon as possible.
The displays for several systems have
malfunctioned. Some systems them-
selves may also have malfunctioned.
Have the electronic systems checked
by an authorized Mercedes-Benz Cen-
ter.
±
Display defective
Visit workshop!
Certain electronic systems are unable to
relay information to the control system.
The following systems may have failed:
Coolant temperature display
Tachometer
Cruise control display
Have the electronic systems checked
by an authorized Mercedes-Benz Cen-
ter.
J
Doors open!
You are attempting to drive with one or
more doors open.
Close the doors.
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Page 332 of 464
332 Practical hintsWhat to do if …?Display symbol
Display message
Possible cause
Possible solution
:
USA only:Add 1 qt. engine oil
when next refuelingCanada only:Add 1 liter engine oil
when next refueling
The engine oil level is too low.
Add engine oil (
page 291) and check
the engine oil level (
page 289).
Engine oil level
Reduce oil level!
You have added too much engine oil.
There is a risk of damaging the engine or
the catalytic converter.
Have oil siphoned or drained off. Ob-
serve all legal requirements with re-
spect to its disposal.
Engine oil level
Stop, engine off!
There is no oil in the engine. There is a
danger of engine damage.
Carefully bring the vehicle to a halt as
soon as possible.
Turn off the engine.
Add engine oil (
page 291) and check
the engine oil level (
page 289).
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Page 333 of 464

333 Practical hints
What to do if …?
When the message
Add 1 qt. engine oil
when next refueling
(Canada:
1 liter
)
appears while the engine is running and at
operating temperature, the engine oil level
has dropped to approximately the
minimum level.When this occurs, the warning will first
come on intermittently and then stay on if
the oil level drops further.
Visually check for oil leaks. If no obvious oil
leaks are noted, drive to the nearest ser-
vice station where the engine oil should be
topped to the required level with an ap-
proved oil.
Display symbol
Display message
Possible cause
Possible solution
:
Engine oil
Visit workshop!
It may be that there is water in the engine
oil.
Have the engine oil checked.
Engine oil level
Visit workshop!
The engine oil has dropped to a critical
level.
Check the engine oil level
(page 289) and add oil as required
(page 291).
If you must add engine oil frequently,
have the engine checked for possible
leaks.
The measuring system is malfunctioning.
Have the measuring system checked
by an authorized Mercedes-Benz
Center.!The engine oil level warnings should
not be ignored. Extended driving with
the symbol displayed could result in
serious engine damage that is not
covered by the Mercedes-Benz Limited
Warranty.
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Page 334 of 464

334 Practical hintsWhat to do if …?Display symbol
Display message
Possible cause
Possible solution
A
Reserve fuel
The fuel level has dropped below the re-
serve mark.
Refuel at the next gas station
(page 284).
Y
Hood open!
You are driving with the hood open.
Close the hood (
page 288).
I
Remove key
You have forgotten to remove the
SmartKey.
Remove the SmartKey from the start-
er switch.
Replace key!
No additional code available for SmartKey
or SmartKey with KEYLESS-GO*
Visit an authorized Mercedes-Benz
Center as soon as possible.
Key
Check battery!
The SmartKey with KEYLESS-GO* batter-
ies are discharged.
Change the batteries (
page 350).
Key
not recognized!
The SmartKey with KEYLESS-GO* is not
recognized while the engine is running be-
cause
the SmartKey is not in the vehicle
there is strong radio-frequency inter-
ference
Stop the vehicle as soon as it is safe to
do so.
Search for the SmartKey.
Otherwise the vehicle cannot be centrally
locked nor can the engine be started
again after the engine has been stopped.
The SmartKey with KEYLESS-GO* is mo-
mentarily not recognized.
Change the position of the SmartKey
in the vehicle.
Operate the vehicle with the SmartKey
in the starter switch if necessary.
Keyless Go
Check system
The KEYLESS-GO* system is malfunction-
ing.
Visit an authorized Mercedes-Benz
Center as soon as possible.
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335 Practical hints
What to do if …?
Display symbol
Display message
Possible cause
Possible solution
I
Key recognized
in vehicle
A SmartKey with KEYLESS-GO* left in the
vehicle was recognized while locking the
vehicle from the outside.
Take the SmartKey out of the vehicle.
Key
do not forget key
This display appears (for a maximum of
60 seconds) if the driver’s door is opened
with the engine shut off and no SmartKey
in the starter switch.
Message is only a reminder.
Insert SmartKey in the starter switch.
Take the SmartKey with
KEYLESS-GO* with you when leaving
the vehicle.
.
3rd stop lamp
The high mounted brake lamp is malfunc-
tioning.
Visit an authorized Mercedes-Benz
Center as soon as possible.
Back- up lamp, left
The left backup lamp is malfunctioning.
Replace the bulb as soon as possible.
Back- up lamp, right
The right backup lamp is malfunctioning.
Replace the bulb as soon as possible.
Display defective
Visit workshop!
The display for the lamps or the system is
malfunctioning.
Visit an authorized Mercedes-Benz
Center as soon as possible.
Front foglamp, left
The left front fog lamp is malfunctioning.
Replace the bulb as soon as possible.
Front foglamp, right
The right front fog lamp is malfunctioning.
Replace the bulb as soon as possible.
High beam, left
The left high beam lamp is malfunction-
ing.
Replace the bulb as soon as possible.
High beam, right
The right high beam lamp is malfunction-
ing.
Replace the bulb as soon as possible.
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336 Practical hintsWhat to do if …?Display symbol
Display message
Possible cause
Possible solution
.
Lamp sensor
Visit workshop!
The lamp sensor is malfunctioning. The
headlamps switch on automatically.
In the control system, set lamp opera-
tion to manual (
page 145).
Switch on headlamps using the exteri-
or lamp switch.
Visit an authorized Mercedes-Benz
Center as soon as possible.
License plate lamp,
left
The left license plate lamp is malfunction-
ing.
Replace the bulb as soon as possible.
License plate lamp,
right
The right license plate lamp is malfunc-
tioning.
Replace the bulb as soon as possible.
Low beam, left
The left low beam lamp is malfunctioning.
Visit an authorized Mercedes-Benz
Center as soon as possible.
Low beam, right
The right low beam lamp is malfunction-
ing.
Visit an authorized Mercedes-Benz
Center as soon as possible.
Parking lamp,
front left
Substitute lamp on
The left parking lamps are malfunctioning.
A backup bulb is being used.
Visit an authorized Mercedes-Benz
Center as soon as possible.
Parking lamp,
front right
Substitute lamp on
The right parking lamps are malfunction-
ing. A backup bulb is being used.
Visit an authorized Mercedes-Benz
Center as soon as possible.
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