Page 305 of 434

304 Practical hintsWhat to do if …
During severe operating conditions, e.g.
stop-and-go traffic, the coolant tempera-
ture may rise close to 248°F (120°C).
Left display
Right display
Possible cause
Possible solution
•
Coolant
Stop, engine off!
The coolant is too hot.
Stop the vehicle and turn off the engine.
Only start the engine again after the message
disappears. You could otherwise 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 engine 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.
Page 306 of 434
305 Practical hints
What to do if …
Left display
Right display
Possible cause
Possible solution
•
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 en-
gine will overheat due to an inoperative water
pump which may result in damage to the en-
gine. Notify an authorized Mercedes-Benz
Center.
If it is intact:
Do not continue to drive with this message
displayed. Doing so could result in serious en-
gine damage that is not covered by the
Mercedes-Benz Limited Warranty.
•
Coolant
Visit
workshop!
The cooling fan for the coolant is
malfunctioning.
Observe the coolant temperature gauge.
Have the fan replaced as soon as possible.
Page 307 of 434

306 Practical hintsWhat to do if …Left display
Right display
Possible cause
Possible solution
G
Display malfunction
Visit
workshop!
The displays for several systems
have malfunctioned. Some systems
themselves may also have malfunc-
tioned.
Continue driving with added caution.
When the display is malfunctioning, warnings
and malfunction messages might not be dis-
played.
Have the electronic systems checked by an
authorized Mercedes-Benz Center.
±
Display defective
Visit workshop!
Certain electronic systems are un-
able to relay information to the con-
trol system. The following systems
may have failed:
Coolant temperature gauge
Tachometer
Cruise control display
Have the electronic systems checked by an
authorized Mercedes-Benz Center
(page 285).
J
Door open!
You are attempting to drive with
one or more doors open.
Close the doors.
_
Entry position
Do not drive!
Seat, mirrors and steering wheel
have not yet moved into their preset
driving positions.
Wait until the seat, mirrors and steering wheel
have moved to their driving positions.
The message disappears.
Page 308 of 434
307 Practical hints
What to do if …
Left display
Right display
Possible cause
Suggested solution
:
USA only:Add 1 qt engine oil
at next refuelingCanada only:Add 1 l engine oil
at next refueling
The engine oil level is too low.
Add engine oil (
page 257) and check the
engine oil level (page 255).
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 257) and check the
engine oil level (page 255).
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 excess oil siphoned or drained off. Ob-
serve all legal requirements with respect to its
disposal.
Page 309 of 434

308 Practical hintsWhat to do if …When the message
Add 1 qt engine oil
at next refueling (Canada:
1l
) 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.
If no oil leaks are noted, continue to drive
to the nearest service station where the
engine oil should be topped to the required
level with an approved oil.
Left display
Right display
Possible cause
Suggested 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 crit-
ical level.
Check the engine oil level (
page 255) and
add oil as required (
page 257).
If you must add engine oil frequently, have the
engine checked for possible leaks.
The measuring system is malfunc-
tioning.
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.
Page 310 of 434
309 Practical hints
What to do if …
Left display
Right display
Possible cause
Possible solution
A
Reserve fuel
The fuel level has dropped below
the reserve mark.
Refuel at the next gas station (
page 250).
Check
gas cap!
See Oper’s Man.
The fuel cap is not closed tightly.
Check the fuel cap (
page 250).
K
Visit
workshop!
The retractable hardtop is malfunc-
tioning.
Have the retractable hardtop checked by an
authorized Mercedes-Benz Center.
K
Lock
Vario-Roof
The retractable hardtop is not
locked properly.
Push or pull on the retractable hardtop switch
until the indicator lamp in the switch goes out
and the retractable hardtop is completely
open or closed (
page 184).
O
Close hood!
You are driving with the hood open.
Close the hood (
page 254).
I
Remove
key!
You have forgotten to remove the
SmartKey.
Remove the SmartKey from the starter
switch.
Replace
key!
The batteries in the SmartKey are
discharged.
Change the batteries (
page 328).
Page 311 of 434
310 Practical hintsWhat to do if …Left display
Right display
Possible cause
Possible solution
F
Key
Check battery!
The batteries in the SmartKey with
KEYLESS-GO* are discharged.
Change the batteries (
page 328).
Key
Do not forget!
This message appears (for a maxi-
mum 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.
KEYLESS GO
Check system
The KEYLESS-GO* system is mal-
functioning.
Visit an authorized Mercedes-Benz Center as
soon as possible.
KEYLESS-GO
Drive to
workshop!
The KEYLESS-GO* system is mal-
functioning.
Visit an authorized Mercedes-Benz Center as
soon as possible.
Page 312 of 434

311 Practical hints
What to do if …
Left display
Right display
Possible cause
Possible solution
F
Key
not recognized!
The SmartKey with KEYLESS-GO* is
not recognized while the engine is
running because
the SmartKey with
KEYLESS-GO* is not in the vehi-
cle
there is strong radio-frequency
interference
Stop the vehicle as soon as it is safe to do so.
Search for the SmartKey with KEYLESS-GO*
or continue to operate the vehicle with the
SmartKey.
Otherwise the vehicle cannot be centrally
locked nor can the engine be started again af-
ter the engine is stopped.
The SmartKey with KEYLESS-GO* is
momentarily not recognized.
Change the position of the SmartKey with
KEYLESS-GO* in the vehicle.
Operate the vehicle with the SmartKey if
necessary.
F
Key
still
in vehicle!
A SmartKey with KEYLESS-GO* left
in the vehicle was recognized while
locking the vehicle from the out-
side.
Take the SmartKey with KEYLESS-GO* out of
the vehicle.
.
3rd brake light
The high mounted brake lamp is
malfunctioning.
Visit an authorized Mercedes-Benz Center as
soon as possible.
Brake lamp
Left
Back-up
lamp on!
The left brake lamp is malfunction-
ing. A backup bulb has been
brought into use.
Visit an authorized Mercedes-Benz Center as
soon as possible.