
77 Checking engine oil level 
Te ch n ica l
data Instruments 
and controlsOperationDrivingInstrument 
cluster displayPractical hints Car care Index Checking engine oil level 
(model SLK 320)
Turn electronic key in steering lock to position 2 and 
wait until the symbols : and I appear in the 
odometer display field.
Within 1 second press left button on the instrument 
cluster twice.The following messages are available:
“OK”
“-1.0 Q” (Canada: -1.0 L)
“-1.5 Q” (Canada: -1.5 L)
“-2.0 Q” (Canada: -2.0 L)
If the message “-2.0 Q” (Canada: -2.0 L) blinks and a 
signal sounds, add oil to upper (max) mark of the 
dipstick.
“HI”
The message “HI” blinks and a signal sounds.
Do not overfill the engine.
Excessive oil must be drained or siphoned. It could 
cause damage to engine and catalytic converter not 
covered by the Mercedes-Benz Limited Warranty.
The symbol I f la sh es in th e od ome ter display f ield  if 
a proper oil level check cannot be performed.
The oil level check can be repeated after a short time.
Perform the oil level check with the dipstick, if it cannot 
be compl eted  via t he od ometer display f iel d. In t his case 
we recommend that you have the system checked at a 
Mercedes-Benz Center. 

78 Checking engine oil level 
Te ch n ica l
data Instruments 
and controlsOperationDrivingInstrument 
cluster displayPractical hints Car care Index
Notes:
If the symbols : and I are continuously 
illuminated after pressing button “1” on the instrument 
cluster twice and there is no change in the odometer 
display field or the low engine oil level warning lamp 
comes on, a malfunction has occurred to the system. 
Perform the engine oil level check with the dipstick.
If no oil leaks are noted continue to drive to the nearest 
Mercedes-Benz Center to have the system checked.Engine oil consumption
Engine oil consumption checks should only be made 
after the break-in period. During the break-in period, 
higher oil consumption may be noticed and is normal. 
Frequent driving at high engine speeds results in 
increased consumption. 

175 What you should know at the gas station
Te ch n ica l
data Instruments 
and controlsOperationDrivingInstrument 
cluster displayPractical hints Car care Index Engine oil
Engine oil level check, see page 193.
Fil l qua ntity between u pper a nd  l owe r dipstick  ma rking  
level: 2.1 US qt (2.0 l).
Recommended engine oils, see Approved Service 
Products sheet.
Coolant
For normal replenishing, use water (potable water 
quality).
For further information (e.g. anticorrosion / antifreeze), 
see page 256.
Spark plugs
Approved spark plugs, see page 251.
Tire pressure
For tire pressure, refer to tire pressure label inside the 
fuel filler flap.Air conditioner
R-134a refrigerant and special PAG lubricant, see 
page 252.
Bulbs
High and low beams (Halogen): H7 (55 W),
fog lamps: H1 (55 W),
turn signal lamps, parking and standing lamps, front: 
2357 NA (28.5 / 8.3 W / 30 / 2.2 cp),
side marker lamps, front: 5 W / 4 cp
stop lamps: 1154 21 W / 32 cp,
backup lamps: 1154 21 W / 32 cp,
turn signal lamps, rear: 1156 NA 21 W / 24cp,
tail, parking and standing lamps: 67 5 W / 4cp,
rear fog lamp, driver´s side: 1155 21 W / 32 cp,
license plate lamps: 67 5 W / 4 cp
Xenon bulb for low beam: D2R (35W)
Wa r n i n g !
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. 

184 Malfunction and indicator lamps
Te ch n ica l
data Instruments 
and controlsOperation DrivingInstrument 
cluster displayPractical hints Car care Index
Low engine oil level warning lamp
With the key in steering lock position 2, the 
oil level warning lamp comes on. It should 
go out immediately when the engine is 
running.
If the warning lamp does not go out after starting the 
engine, or comes on with the engine running and at 
operating temperature, the engine oil level has dropped 
to approximately the minimum mark on the dipstick.
When this occurs, the warning lamp will first come on 
intermittently and then stay on if the oil level drops 
further.
If no leaks are noted, continue to drive to the nearest 
service station where the engine oil should be topped to 
the “full” mark on the dipstick with an approved oil.
The low engine oil level warning light should not be 
ignored. Extended driving with the light illuminated 
could result in serious engine damage that is not 
covered by the Mercedes-Benz Limited Warranty.
In addition to the warning lamp, the engine oil level 
should be periodically checked with the dipstick, for 
example during a fuel stop, or before a long trip, see 
page 193.Charge indicator lamp
Should the charge indicator lamp fail to 
come on prior to starting when the key is in 
ste ering lock position 2 or sh ou ld  it fa il to g o 
out after starting or during operation, this indicates a 
malfunction which must be repaired immediately at an 
authorized Mercedes-Benz Center.
If t he charg e ind ica tor l amp comes on, or a l oss of  power 
steering assistance is noticeable while the engine is 
running, this may indicate that one of the two poly-V-
belts has broken. Should this condition occur, the poly-
V-belt mu st be replac ed before continuing to operate  t he 
vehicle. Otherwise, the engine may overheat due to an 
inoperative water pump which may result in damage to 
the engine.
Do not continue to drive the vehicle with the charge 
indicator lamp illuminated. Doing so could result in 
serious engine damage that is not covered by the 
Mercedes-Benz Limited Warranty. 

193 Checking engine oil level
Te ch n ica l
data Instruments 
and controlsOperation DrivingInstrument 
cluster displayPractical hintsCar care Index Checking engine oil level
1Oil dipstick
2Oil filler cap
To check the engine oil level, park vehicle on level 
ground, with engine at normal operational temperature.
Check engine oil level approximately 5 minutes after 
stopping the engine, allowing for the oil to return to the 
oil pan.Wipe oil dipstick clean prior to checking the engine oil 
level. Fully insert dipstick in tube, and remove after 
three seconds to obtain accurate reading.
Oil level must be between the lower 
(min) and upper (max) mark of the 
dipstick.
Fill qu antity b etween u pper a nd l ower dipstick m arking  
level is approximately 2.1 US qt (2.0l).
Do not overfill the engine.
Excessive oil must be drained or siphoned. It could 
cause engine damage not covered by the Mercedes-Benz 
Limited Warranty.
For low engine oil level warning, see page 184.
P18.40-2047-262
1 

261 Index
Te ch n ica l
data Instruments 
and controlsOperation DrivingInstrument 
cluster displayPractical hints Car careIndex Brake assist system (BAS)  ............................................ 166
Malfunction indicator lamp ..................................... 181
Brake fluid  ......................................................................254
Brake pad wear indicator lamp .................................... 180
Brake warning lamp  ...................................................... 179
Brake fluid low  .......................................................... 179
Brakes  .....................................................155, 166, 168, 170
CCapacities
Fuels, coolants, lubricants etc.  ...............................252
Catalytic converter  ........................................................ 138
Cellular telephone  ..........................................................116
Center console .................................................................. 18
Central locking switch  .................................................... 30
Central locking system  ................................................... 25
Automatic central locking  ......................................... 31
Choosing global or selective mode ........................... 26
Emergency release for trunk lid ............................... 35
General notes ............................................................... 24
Locking and unlocking  .............................................. 26
Remote control  ............................................ 22, 25, 224
Vehicle keys  ................................................................. 22Changing wheels ........................................................... 202
Inflating the collapsible spare tire  ........................ 207
Storing spare wheel in wheel well  ........................ 208
Charge indicator lamp  ................................................... 184
Check engine malfunction indicator lamp .................178
Check regularly and before a long trip ....................... 176
Checking engine oil level
Via engine oil level  .....................................................77
Via oil dipstick  ........................................................... 193
Child restraint  ...............................................44, 50, 51, 61
Cleaning and care of the vehicle  ................................ 234
Climate control  .................................................................84
Air Recirculation  .........................................................89
Basic setting .................................................................86
Defogging windows  .....................................................87
Defrosting  .....................................................................87
Dust Filter .....................................................................90
Rear window defroster  ............................................... 88
Residual Engine Heat Utilization (REST)  ................ 89
Special settings  ........................................................... 87
Clock, setting  .................................................................... 74
Coin Holder  ..................................................................... 114
Combination switch  ......................................................... 81
Consumer information  ................................................. 258
Control and operation of radio transmitters .............. 128