Page 347 of 474

345 Practical hints
What to do if …
Symbol messagesLeft display
Right display
Possible cause
Possible solution
# 
Battery/Alternator
Stop vehicle
The battery is malfunctioning.
The SBC brake system requires 
electrical energy and therefore has 
only limited operation. Consider-
ably greater brake pedal force is re-
quired and the stopping distance is 
increased.
Stop the vehicle as soon as it is safe to do so. 
Adjust driving to be consistent with reduced 
braking responsiveness.
Notify an authorized Mercedes-Benz Center.
Visit
workshop!
The battery is no longer charging. 
Possible causes:
alternator malfunctioning
broken poly-V-belt
Do not forget that the brake system 
requires electrical energy and may 
be operating with restricted capa-
bility. Considerably greater brake 
pedal force is required and the stop-
ping distance is increased.
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 inoperative 
water pump which may result in damage 
to the engine. Notify an authorized 
Mercedes-Benz Center.
If it is in order:
Drive immediately to the nearest autho-
rized Mercedes-Benz Center. Adjust driv-
ing to be consistent with reduced braking 
responsiveness. 
     
        
        Page 351 of 474
349 Practical hints
What to do if …
Left display
Right display
Possible cause
Possible solution
USA only:;Canada only:3
Brake fluid
below min. level
Visit
workshop
There is insufficient brake fluid in 
the reservoir.
Risk of accident! Stop the vehicle 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.
!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.
Warning
G
Driving with this message displayed can re-
sult 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. 
     
        
        Page 353 of 474

351 Practical hints
What to do if …
Left display
Right display
Possible cause
Possible solution
?
Engine
Service
There may be a malfunction in the 
fuel injection system
ignition system
exhaust system
fuel system
Have the engine checked as soon as possible 
by an authorized Mercedes-Benz Center 
(page 327).
B
Coolant
Check level
The coolant level is too low.
Add coolant (
page 276).
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 
this message and symbol displayed 
may cause serious engine damage not 
covered by the Mercedes-Benz Limited 
Warranty. Do not drive without suffi-
cient amount of coolant in the cooling 
system. The engine will overheat, caus-
ing major engine damage. 
     
        
        Page 355 of 474
353 Practical hints
What to do if …
Left display
Right display
Possible cause
Possible solution
•
Coolant
Stop, put 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 357 of 474
355 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 liter
engine oil
at next refueling
The engine oil level is too low.
Add engine oil (
page 274) and check the 
engine oil level (page 272).
Engine oil level
Stop, put 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 274) and check the 
engine oil level (page 272).
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 358 of 474

356 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 specified in the 
Factory Approved Service Products pam-
phlet.
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 272) and 
add oil as required (
page 274).
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 360 of 474
358 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 377).
Don’t forget
key
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 373 of 474
371 Practical hints
What to do if …
Left display
Right display
Possible cause
Possible solution
Ê
Close
trunk lid
This message will appear whenever 
the trunk lid is open.
Close the trunk lid.
M
Close
trunk partition
You are trying to open or close the 
retractable hardtop even though 
the luggage cover in the trunk is not 
pulled out.
Pull out the luggage cover and secure it 
(page 197). 
W
Washer fluid
Check level
The fluid level has dropped to about 1/3 of total reservoir capacity.
Add washer fluid (
page 278).
Warning!
G
Do not spill antifreeze on hot engine parts. 
Antifreeze contains ethylene glycol which 
may ignite when if it comes into contact with 
hot engine parts. You could be seriously 
burned.