Page 59 of 474

58 Getting started
Driving
Single wipe
Press the combination switch briefly in 
direction of arrow1 (
page 58) to 
the resistance point.
The windshield wipers wipe one time 
without washer fluid.
Wiping with windshield washer fluid
Press the combination switch in direc-
tion of arrow1 (
page 58) past the 
resistance point.
The windshield wipers operate with 
washer fluid.
For information on filling up the washer 
reservoir, see “Windshield washer system 
and headlamp cleaning system*” 
(
page 301).
Problems while driving
The engine runs erratically and misfires
An ignition cable may be damaged.
The engine electronics may not be 
operating properly.
Unburned gasoline may have entered 
the catalytic converter and damaged it.
Give very little gas.
Have the problem repaired by an au-
thorized Mercedes-Benz Center as 
soon as possible.
The coolant temperature is above 
248°F (120°C)
The coolant is too hot and is no longer 
cooling the engine.
Stop the vehicle as soon as possible 
and turn off the engine. Allow engine 
and coolant to cool off.
Check the coolant level and add cool-
ant if necessary (
page 300).In case of accident
If the vehicle is leaking gasoline:
Do not start the engine under any 
circumstances.
Notify local fire and/or police 
authorities.
If the extent of the damage cannot be 
determined:
Contact an authorized Mercedes-Benz 
Center or call Roadside Assistance.
If no damage can be determined on the
Major assemblies
Fuel system
Engine mount
Start the engine in the usual manner.
iTo prevent smears on the windshield or 
noisy/chattering wiper blades, wipe with 
windshield washer fluid every now and then even 
when it is raining. 
     
        
        Page 293 of 474

292 Operation
At the gas station
Close the fuel filler flap.
Check regularly and before a long trip
Engine compartment 
(example illustration, SLK 350)
1Windshield washer system and head-
lamp cleaning system* reservoir
2Brake fluid reservoir
3Coolant expansion tankWindshield washer system and head-
lamp cleaning system*
For information on refilling the reservoir, 
see “Windshield washer system and 
headlamp cleaning system*” 
(
page 301).
Brake fluid
For information on brake fluid, see “Fuels, 
coolants, lubricants, etc.” (
page 451).
iMake sure to close the fuel filler flap before 
locking your vehicle as the flap locking pin 
prevents closing after you have locked the 
vehicle.
iOnly use premium unleaded gasoline with a 
minimum Posted Octane Rating of 91 (average 
of 96 RON/86 MON).
Information on gasoline quality can normally be 
found on the fuel pump. Please contact gas 
station personnel in case labels on the pump 
cannot be found.
For more information on gasoline, see “Premium 
unleaded gasoline” (
page 454), refer to the 
Factory Approved Service Products pamphlet 
(USA only), or contact an authorized 
Mercedes-Benz-Center.
iLeaving the engine running and the fuel cap 
open can cause the yellow fuel tank reserve 
warning lamp to flash and the?malfunction 
indicator lamp (USA only) or the 
±malfunction indicator lamp (Canada only) 
to illuminate.
For more information, see “Practical hints” 
(
page 351).
iFor opening the hood, see “Hood” 
(
page 294).
!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 immediately. Notify an 
authorized Mercedes-Benz Center immediately. 
Do not add brake fluid as this will not solve the 
problem.
For more information, see “Practical hints” 
(
page 350).
 
     
        
        Page 301 of 474

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 451) and 
(
page 453).
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.
When checking the coolant level,
the vehicle must be parked on level 
ground
the coolant temperature must be 
below 158°F (70°C)
!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.
Using a rag, slowly open the cap approx-
imately 1/2turn to relieve excess pres-
sure. If opened immediately, scalding 
hot fluid and steam will be blown out 
under pressure.
Do not spill antifreeze on hot engine 
parts. Antifreeze contains ethylene 
glycol which may burn if it comes into 
contact with hot engine parts. 
     
        
        Page 302 of 474

301 Operation
Engine compartment
The coolant expansion tank is located on 
the passenger side of the engine compart-
ment.
SLK 350 (example illustration)
1Coolant expansion tank
2Cap
3Marking bar in the expansion tank
Using a rag, turn cap2 slowly approx-
imately one half turn counterclockwise 
to release any excess pressure.
Continue turning cap2 counterclock-
wise and remove it.
The coolant level is correct if the level 
for cold coolant: reaches marking 
bar3 in expansion tank1
for warm coolant: is approximately 
0.6 in (1.5 cm) higher
Add coolant as required.
Replace and tighten cap2.
For more information on coolant, see 
“Coolants” (
page 456).Windshield washer system and 
headlamp cleaning system*
The windshield washer reservoir is located 
on the passenger side of the engine com-
partment.
SLK 350 (example illustration)
1Cap for windshield washer reservoir
Fluid for the windshield washer system 
and the headlamp cleaning system* is 
supplied from the windshield washer 
reservoir. It has a capacity of 
approximately 7.4 US qt (7 l). 
     
        
        Page 459 of 474

458 Technical data
Fuels, coolants, lubricants, etc.
Windshield washer system and 
headlamp cleaning system*
Both the windshield washer system and 
headlamp cleaning system* are supplied 
from the windshield washer reservoir.
The windshield washer reservoir has a 
capacity of approximately 7.4 US qt (7.0 l).
Refill the reservoir with MB Windshield 
Washer Concentrate “MB SummerFit” 
and water (or concentrate and 
commercially available premixed wind-
shield washer solvent/antifreeze, de-
pending on ambient temperatures).Windshield and headlamp washer fluid 
mixing ratio
For temperatures above freezing point, 
use MB Windshield Washer Concentrate 
“MB SummerFit” and water:
1 part “MB SummerFit” to100 parts 
water
(1.34 fl oz [40 ml] “MB SummerFit” to 
1gal [4.0l] water)For temperatures below freezing point, use 
MB Windshield Washer 
Concentrate “MB SummerFit” and com-
mercially available premixed windshield 
washer solvent/antifreeze:
1 part “MB SummerFit” to 100 parts 
solvent
(1.34 fl oz [40 ml] “MB SummerFit” to 
1 gal [4.0 l] solvent)
Warning!G
Washer solvent/antifreeze is highly flamma-
ble. Do not spill washer solvent/antifreeze 
on hot engine parts because it may ignite 
and burn. You could be seriously burned.