Page 365 of 489

364 Practical hintsWhat to do if …?Problem
Possible cause/consequence
Suggested solution
•
The red coolant warning lamp
comes on when the engine is
running.
There is insufficient coolant in the reservoir.
Add coolant to prevent engine from
overheating (
page 314).
If this warning lamp comes on frequently,
there is a leak in the cooling system.
Have the cooling system checked.
If the coolant level is correct, the electric ra-
diator fan may be broken.
If the coolant temperature is below
257 °F (125 °C), you can continue
driving to the nearest authorized
Mercedes-Benz Center.
Avoid high engine loads (e.g. driving
uphill) and stop-and-go driving.
•
The red coolant warning lamp
comes on while driving and you
hear a warning sound.
The coolant temperature has exceeded
257 °F (125 °C).
Stop as soon as possible and allow
the engine and coolant to cool down.
Warning!
G
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 open-
ing 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.
Page 383 of 489
382 Practical hintsWhat to do if …?Symbol messagesDisplay symbol
Display message
Possible cause/consequence
Possible solution
#
Visit workshop
The battery is no longer charging.
Possible causes:
broken poly-V-belt
alternator malfunctioning
Stop immediately in a safe location or
as soon as it is safe to do so and check
the poly-V-belt.
If it is broken:
Do not continue to drive. Otherwise
the engine will overheat due to an
inoperative water pump which may
result in damage to the engine. Notify
an authorized Mercedes-Benz Center.
If it is intact:
Drive immediately to the nearest
authorized Mercedes-Benz Center.
Low voltage
Charge battery
The battery has insufficient voltage.
Start the engine (
page 48).
Low voltage
Switch off
consumers
The battery has insufficient voltage.
Turn off unnecessary electrical con-
sumers.
Page 384 of 489

383 Practical hints
What to do if …?
Display symbol
Display message
Possible cause/consequence
Possible solution
2
Brake wear
Visit workshop
The brake pads have reached their
wear limit.
Have the brake pads replaced as soon as
possible.
;
(USA only)
!
(Canada only)
Release parking
brake
You are driving with the parking brake
set.
Release the parking brake (
page 50).
3
Brake fluid
Visit workshop
There is insufficient brake fluid in the
reservoir.
Risk of accident! Stop the vehicle in a safe
location or as soon as it is safe to do so
and notify an authorized Mercedes-Benz
Center. Do not add brake fluid! This will
not solve the problem.
Warning!
G
Driving with the message “
Brake fluid
Visit workshop
” displayed can result in
an accident. Have your brake system
checked immediately. Do not add brake flu-
id before checking the brake system. Over-
filling the brake fluid reservoir can result in
spilling brake fluid on hot engine parts and
the brake fluid catching fire. You can be se-
riously burned.
!If you find that the brake fluid in the
brake fluid reservoir has fallen to the
minimum mark or below, have the
brake system checked for brake pad
thickness and leaks.
!Brake pad thickness must be visually
checked by a qualified technician at the
intervals specified in the Maintenance
Booklet.
Page 385 of 489

384 Practical hintsWhat to do if …?Display symbol
Display message
Possible cause/consequence
Possible solution
ú
Visit workshop
There may be a malfunction in the
fuel injection system
ignition system
exhaust system
fuel system
Have the measuring system checked
by an authorized Mercedes-Benz Cen-
ter.
B
Coolant
Check level
The coolant level is too low.
Add coolant (
page 314).
If you have to add coolant frequently,
have the cooling system checked by
an authorized Mercedes-Benz Center.
Warning!
G
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 can be seriously burned.
!Do not ignore the low engine coolant
level warning. Extended driving with
the message and symbol displayed
may cause serious engine damage not
covered by the Mercedes-Benz Limited
Warranty.
Do not drive without sufficient amount
of coolant in the cooling system. The
engine will overheat, causing major en-
gine damage.
Page 387 of 489
386 Practical hintsWhat to do if …?Display symbol
Display message
Possible cause/consequence
Possible solution
•
Coolant
Stop, engine off
The poly-V-belt could be broken.
Stop the vehicle in a safe location or as soon
as it is safe to do so and immediately turn off
the engine.
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 the vehicle with this
message displayed. Doing so could result in
serious engine damage that is not covered by
the Mercedes-Benz Limited Warranty.
Drive immediately to the nearest authorized
Mercedes-Benz Center.
Coolant
Visit workshop
The cooling fan for the coolant is mal-
functioning.
Observe the coolant temperature display.
Have the fan replaced as soon as possible.
Page 389 of 489
388 Practical hintsWhat to do if …?Display symbol
Display message
Possible cause/consequence
Possible solution
:
USA only:Add 1 qt. engine oil
at next refuelingCanada only:Add 1 liter engine oil
at next refueling
The engine oil level is too low.
Add engine oil (
page 312) and check
the engine oil level (
page 310).
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 312) and check
the engine oil level (
page 310).
Page 390 of 489

389 Practical hints
What to do if …?
When the message
Add 1 qt. engine oil
at next refueling (Canada:
1 liter
) ap-
pears 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
approved oil specified in the Factory
Approved Service Products pamphlet.
Display symbol
Display message
Possible cause/consequence
Possible solution
:
Engine oil level
Visit workshop
The engine oil has dropped to a critical
level.
Check the engine oil level
(page 310) and add oil as required
(page 312).
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.
Page 391 of 489

390 Practical hintsWhat to do if …?Display symbol
Display message
Possible cause/consequence
Possible solution
A
Reserve fuel
The fuel level has dropped below the re-
serve mark.
Refuel at the next gas station
(page 305).
Y
Hood open
You are driving with the hood open.
Close the hood (
page 309).
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 409).
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.