Page 315 of 464

315 Practical hints
What to do if …?
Problem
Possible cause
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 292).
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 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. 
     
        
        Page 329 of 464

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. 
     
        
        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. 
     
        
        Page 375 of 464

375 Practical hints
Replacing bulbs
Low beam and high beam bulb
Switch off the lights.
Open the hood (
page 287).
Turn housing cover1 or 2 counter-
clockwise and remove.
Turn bulb holder 4 or 5 with the bulb 
counterclockwise and remove.
Press the bulb backwards and turn 
counterclockwise out of the bulb hold-
er.
Press the new bulb into the holder and 
twist it clockwise.
Place the bulb holder back into the 
lamp and turn it clockwise.
Place the corresponding housing cov-
ers back on and turn them clockwise.Front turn signal lamp bulb
Switch off the lights.
Open the hood (
page 287).
Twist bulb socket3 counterclockwise 
and pull out.
Push bulb into socket, turn counter-
clockwise and remove.
Insert new bulb in socket, push in and 
twist clockwise.
Reinsert bulb socket in lamp and twist 
clockwise.Parking and standing lamp bulb
Switch off the lights.
Open the hood (
page 287).
Turn housing cover2 counterclock-
wise and remove.
Pull out the bulb socket with the bulb.
Pull the bulb out of the bulb socket.
Insert a new bulb in the socket.
Reinstall the bulb socket.
Align housing cover and click into 
place. 
     
        
        Page 376 of 464
376 Practical hintsReplacing bulbsFront lamps Bi-Xenon*-type
1Bulb socket for turn signal lamp
2Housing cover for high beam flasher 
lamp
3Housing cover for Bi-Xenon* lamp4High beam flasher bulb
5Parking and standing lampHigh beam bulb for high beam flasher
Switch off the lights.
Open the hood (
page 287).
Turn housing cover2 counterclock-
wise and remove.
Turn bulb holder 4 with the bulb coun-
terclockwise and remove.
Press the bulb backwards and turn 
counterclockwise out of the bulb hold-
er.
Press the new bulb into the holder and 
twist it clockwise.
Place the bulb holder back into the 
lamp and turn it clockwise.
Place the housing cover 2 back on 
and turn them clockwise.
Warning!
G
Do not remove the cover 
3
 for the Bi-Xe-
non* headlamp. Because of high voltage in 
xenon lamps, it is dangerous to replace the 
bulb or repair the lamp and its components. 
We recommend that you have such work 
done by a qualified technician. 
     
        
        Page 377 of 464
377 Practical hints
Replacing bulbs
Front turn signal lamp bulb
Switch off the lights.
Open the hood (
page 287).
Twist bulb socket1 counterclockwise 
and pull out.
Push bulb into socket, turn counter-
clockwise and remove.
Insert new bulb in socket, push in and 
twist clockwise.
Reinsert bulb socket in lamp and twist 
clockwise.Parking and standing lamp bulb
Switch off the lights.
Open the hood (
page 287).
Turn housing cover2 counterclock-
wise and remove.
Pull out the bulb socket with the bulb.
Pull the bulb out of the bulb socket.
Insert a new bulb in the socket.
Reinstall the bulb socket.
Align housing cover and click into 
place.
Side marker lamp bulb
Switch off the lights.
Carefully slide lamp towards rear.
Remove front end first.
Twist bulb socket counterclockwise 
and pull out.
Pull bulb out of the bulb socket.
Insert new bulb in socket.
Reinstall bulb socket, push in and twist 
clockwise.
To reinstall lamp, set rear end in 
bumper and let front end snap into 
place. 
     
        
        Page 379 of 464

379 Practical hints
Replacing wiper blades
Replacing wiper blades
Removing wiper blades
Fold the wiper arm forward.
1Lock
2Unlock
Pull the tab in direction of arrow2 and 
remove windshield wiper.
Installing wiper blades
Slide the wiper blade into the cutout on 
the wiper arm.
Slide the tab back in direction of 
arrow1 until it audibly engages.
Fold the wiper arm backward to rest on 
the windshield. Make sure you hold on 
to the wiper when folding the wiper arm 
back.
Warning!
G
For safety reasons, remove SmartKey from 
starter switch before replacing a wiper 
blade. Otherwise the motor could suddenly 
turn on and cause injury.
!Never open the hood when the wiper 
arms are folded forward.
Hold on to the wiper when folding the 
wiper arm back. If released, the force 
of the impact from the tensioning 
spring could crack the windshield.
Do not allow the wiper arms to contact 
the windshield glass without a wiper 
blade inserted.
Make certain that the wiper blades are 
properly installed. Improperly installed 
wiper blades may cause windshield 
damage.
For your convenience, we recommend 
that you have this work carried out by 
an authorized Mercedes-Benz Center. 
     
        
        Page 386 of 464

386 Practical hintsBatteryDisconnecting the battery
1Negative terminal
2Positive terminal cover
Depress parking brake firmly or move 
gear selector lever to positionP.
Turn off all electrical consumers.
Remove SmartKey from starter switch.
Vehicles with KEYLESS-GO*:
Press the start / stop button until 
the engine shuts off.
Open the driver’s door.
Open the hood (
page 287).
Remove the filter box.
Disconnect the battery negative lead.
Remove cover2 from the positive ter-
minal.
Disconnect the battery positive lead.
Removing the battery
Remove the screw securing the bat-
tery.
Remove the battery support and brack-
et.
Take out the battery.
Charging and reinstalling battery
Charge battery in accordance with the 
instructions of the battery charger 
manufacturer.
Reinstall the charged battery. Follow 
the previously described steps in re-
verse order.
Warning!
G
With a disconnected battery
you will no longer be able to turn the 
SmartKey in the starter switch and 
pressing the KEYLESS-GO* start/stop 
button on the gear selector lever will 
have no effect
the gear selector lever will remain 
locked in position
P
Warning!
G
Never charge a battery while still installed in 
the vehicle. Gases may escape during charg-
ing and cause explosions that may result in 
paint damage, corrosion or personal injury.