Page 296 of 473

295 Operation
Engine compartment
Pull hood lock release lever1 in direc-
tion of arrow.
The hood is unlocked.
2Lever for opening the hood
Push lever2 on the hood upward to 
release hood.
With the hood released, lift the hood by 
lifting it at the front edge.
The hood will be automatically held 
open at shoulder height by gas-filled 
struts.
ClosingLet the hood drop from a height of 
approximately 1 ft (30 cm).
The hood will lock audibly.
Check to make sure the hood is fully 
closed. 
If you can raise the hood at a point 
above the headlamps, then it is not 
properly closed. Open it again and let it 
drop with somewhat greater force.!To avoid damage to the windshield wipers or 
hood, never open the hood if the wiper arms are 
folded forward away from the windshield.
Warning!G
When closing the hood, use extreme caution 
not to catch hand or fingers. Be careful that 
you do not close the hood on anyone.
Make sure the hood is securely engaged be-
fore driving. Do not continue driving if the 
hood can no longer engage after an accident 
for example. The hood could otherwise 
come loose while the vehicle is in motion 
and injure you and/or others. 
     
        
        Page 299 of 473

298 Operation
Engine compartment
If there is excess engine oil with the engine 
at normal operating temperature, the 
following message will appear:
Engine oil level
Reduce oil level
Have excess oil siphoned or drained 
off. Contact an authorized 
Mercedes-Benz Center.
For more information on messages in the 
display concerning engine oil, see the 
“Practical hints” section (
page 356).Checking engine oil level with the oil 
dipstick (SLK 280, SLK 350 only)
When checking the oil level
the vehicle must be parked on level 
ground.
with the engine at operating tempera-
ture, the vehicle must have been 
stationary for at least 5 minutes with 
the engine turned off.
with the engine not at operating tem-
perature, the vehicle must have been 
stationary for at least 30 minutes with 
the engine turned off.1Oil dipstick
2Upper (max) mark
3Lower (min) mark
To check the engine oil level with the oil 
dipstick, do the following:
Open the hood (page 294).
Pull out oil dipstick1.
Wipe oil dipstick1 clean.
Fully insert oil dipstick1 into the 
dipstick guide tube.
!Excess oil must be siphoned or drained off. 
It could cause damage to the engine and 
catalytic converter not covered by the 
Mercedes-Benz Limited Warranty. 
     
        
        Page 301 of 473

300 Operation
Engine compartment
Unscrew filler cap1 from filler neck.
Add engine oil as required.
Be careful not to overfill with oil.
Be careful not to spill any oil when adding. 
Avoid environmental damage caused by oil 
entering the ground or water.
Screw filler cap1 back on filler neck.
For more information on engine oil, see 
“Technical data” (
page 443) and 
(
page 445).
Transmission fluid level*
Vehicles with automatic transmission*: 
The transmission fluid level does not need 
to be checked. If you notice transmission 
fluid loss or gear shifting malfunctions, 
have an authorized Mercedes-Benz Center 
check the transmission.Coolant level
The engine coolant is a mixture of water 
and anticorrosion/antifreeze. To check 
the coolant level, the vehicle must be 
parked on level ground and the engine 
must be cool.
!Excess oil must be siphoned or drained off. 
It could cause damage to the engine and 
emission control system not covered by the 
Mercedes-Benz Limited Warranty.Warning!G
In order to avoid any potentially serious 
burns:
Use extreme caution when opening the 
hood if there are any signs of steam or 
coolant leaking from the cooling system, 
or if the coolant temperature gauge indi-
cates that the coolant is overheated.
Do not remove pressure cap on coolant 
reservoir if coolant temperature is 
above 158°F (70°C). Allow engine to 
cool down before removing cap. The 
coolant reservoir contains hot fluid and 
is under pressure. 
     
        
        Page 341 of 473

340 Operation
Vehicle care
Ornamental moldings
For regular cleaning and care of very dirty 
chrome-plated parts, use a chrome clean-
er.Headlamps, tail lamps, side makers, 
turn signal lenses
Use a mild car wash detergent, such as 
Mercedes-Benz approved Car 
Shampoo, with plenty of water.Cleaning the windows and the wiper 
blades
Make sure the hood is fully closed.
Switch on the ignition (page 37).
Turn combination switch to wiper 
settingII (
page 56).
With wiper arms in vertical position, 
switch off the ignition (
page 37).
iAfter running the vehicle through an 
automatic car wash, wipe any wax off of the 
windshield (
page 340). This will prevent 
smears and reduce wiping noise which can be 
caused by residual wax on the windshield.
When leaving the car wash, make sure that the 
mirrors are folded out. Otherwise they may 
vibrate.
!Do not use chrome cleaner on ornamental 
moldings. Although ornamental moldings may 
have chrome appearance, they could be made of 
anodized aluminum that will be damaged when 
cleaned with chrome cleaner. Instead, use a 
damp cloth to clean those ornamental moldings.
For very dirty ornamental moldings of which 
you are sure are chrome-plated, use a chrome 
cleaner. If in doubt whether an ornamental mold-
ing is chrome-plated, contact an authorized 
Mercedes-Benz Center.
!Only use window cleaners that are suitable 
for plastic lamp lenses. Window cleaning solu-
tions which are not suitable may damage the 
plastic lamp lenses of the headlamps. Therefore, 
do not use abrasives, solvents or cleaners that 
contain solvents.
Never apply strong force and use only a soft, 
non-scratchy cloth when cleaning the lenses. Do 
not attempt to wipe dirty lenses with a dry cloth 
or sponge.
Otherwise you may scratch or damage the lens 
surface.
!The windshield wipers must be in a vertical 
position before folding them away from the wind-
shield. They could otherwise damage the hood.
Never open the hood when the wiper arms are 
folded forward.
Warning!G
For safety reasons, switch off wipers and 
remove SmartKey from starter switch be-
fore cleaning the windshield and/or the wip-
er blades. Otherwise, the wiper motor could 
suddenly turn on and cause injury. 
     
        
        Page 370 of 473

369 Practical hints
What 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).
Display symbolDisplay messagePossible cause/consequencePossible solution
Observe the coolant temperature display 
(
page 127).
If the temperature rises again:
Contact an authorized Mercedes-Benz 
Center immediately.
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 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 376 of 473

375 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
OYou are driving with the hood open.Risk of accident!
Stop the vehicle in a safe location or as soon 
as it is safe to do so.
Apply the parking brake (page 59).
Close the hood (page 294).
IPlease
get a new keyThe SmartKey is malfunctioning.Contact an authorized Mercedes-Benz 
Center.
Remove keyYou have forgotten to remove the 
SmartKey from the starter switch.Remove the SmartKey from the starter 
switch.
.3rd brake lampThe high mounted brake lamp is 
malfunctioning. This message will 
only appear if a critical number of 
LEDs have stopped working.Contact an authorized Mercedes-Benz 
Center as soon as possible.
AUTO-Light
inoperativeThe light sensor is malfunctioning. 
The headlamps switch on automati-
cally.Contact an authorized Mercedes-Benz 
Center as soon as possible.
To switch off the headlamps (U.S. vehicles only):
In the control system, set lamp operation to 
manual mode (
page 143).
Switch off headlamps using the exterior 
lamp switch (
page 109). 
     
        
        Page 397 of 473
396 Practical hints
Replacing bulbs
Replacing bulbs for front lamps
Before you start to replace a bulb for a 
front lamp, do the following first:
Turn the exterior lamp switch to 
positionM (
page 109).
Open the hood (page 294).
1Housing cover for low beam (halogen 
headlamps only)
Housing cover for Bi-Xenon* head-
lamps. Do not remove.
2Bulb socket for turn signal lamp
3Bulb socket for high beam/high beam 
flasher lamp
4Bulb socket for parking and standing 
light lamp
5Bulb socket for low beam bulb 
(Halogen headlamps only)
Warning!G
Do not remove the cover1 for the 
Bi-Xenon* headlamp. Because of high volt-
age in Bi-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 400 of 473

399 Practical hints
Replacing wiper blades
Replacing wiper blades
Placing wiper arms in vertical position
1Wiper arms
Turn the SmartKey in the starter switch 
to position1 (
page 37).
Turn combination switch to wiper 
settingII (
page 56).
With wiper arms 1 in vertical position, 
turn the SmartKey in the starter switch 
to position0.
Remover the SmartKey from the starter 
switch.
Warning!G
For safety reasons, switch off wipers and 
remove the SmartKey from the starter 
switch before replacing a wiper blade. 
Otherwise, the motor could suddenly turn 
on and cause injury.
Warning!G
Wiper blades are components that are 
subject to wear and tear. Replace the wiper 
blades twice a year, preferably in the spring 
and fall. Otherwise the windows will not be 
properly wiped. As a result, you may not 
be able to observe surrounding traffic condi-
tions and could cause an accident. 
!To avoid damage to the hood: 
The wiper arms should only be folded for-
ward when in the vertical position.
Never open the hood when a wiper arm is 
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 wind-
shield.
Do not allow the wiper arms to contact the wind-
shield glass without a wiper blade inserted.
For your convenience, we recommend that you 
have this work carried out by an authorized 
Mercedes-Benz Center.