Page 143 of 290

140 Catalytic converter
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Catalytic converter
Your Mercedes-Benz is equipped with monolithic type
catalytic converters, an important element in
conjunction with the oxygen sensors to achieve
substantial control of the pollutants in the exhaust
emissions. Keep your vehicle in proper operating
condition by following our recommended maintenance
instructions as outlined in your Service Booklet.
Caution!
To prevent damage to the catalytic converters, use only
premium unleaded gasoline in this vehicle.
Any noticeable irregularities in engine operation should
be repaired promptly. Otherwise, excessive unburned
fuel may reach the catalytic converter causing it to
overheat, which could start a fire.
Wa r n i n g !
As with any vehicle, do not idle, park or operate
this vehicle in areas where combustible materials
such as grass, hay or leaves can come into contact
with the hot exhaust system, as these materials
could be ignited and cause a vehicle fire.
Page 146 of 290
143 Steering lock
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Notes:
A warning sounds when the driver’s door is opened
while the key is in steering lock position 1 or 0.
With the engine at idle speed, the charging rate of the
alternator (output) is limited.
It is therefore recommended that you turn off
unnecessary electrical consumers while driving in stop-
and-go traffic. This precaution helps to avoid draining of
the battery.
Unnecessary strain on the battery and charging system
may be minimized by turning off the following power
consumers, for example: Heated seats, rear window
defroster.Caution!
To prevent accelerated battery discharge and a possible
dead battery, always remove the key from the steering
lock. Do not leave the key in steering lock position 0.
Page 151 of 290

148 Automatic transmission
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Driving
The selector lever is automatically locked while in
position “P”. To move the selector lever out of
position “P”, the service brake pedal must be firmly
depressed before the shift lock will release.
Shift selector lever to the desired position only when the
engine is idling normally and the service brake is
applied. Do not release the brake until ready to drive.
The vehicle may otherwise start creeping when the
selector lever is in drive or reverse position.Important!
After selecting any driving position from “N” or “P”,
wait a moment to allow the gear to fully engage before
accelerating, especially when the engine is cold.
Accelerator position
Partial throttle = early upshifting = normal acceleration
Full throttle = later upshifting = rapid acceleration
Kickdown (depressing the accelerator beyond full
throttle) = downshifting to a lower gear = maximum
acceleration. Once the desired speed is attained, ease up
on the accelerator – the transmission shifts up again.
Wa r n i n g !
It is dangerous to shift the selector lever out of “P”
or “N” if the engine speed is higher than idle speed.
If your foot is not firmly on the brake pedal, the
vehicle could accelerate quickly forward or in
reverse. You could lose control of the vehicle and
hit someone or something. Only shift into gear
when the engine is idling normally and when your
right foot is firmly on the brake pedal.
Page 226 of 290

223 Jump starting
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index Proceed as follows:
1. Position the vehicle with the charged battery so that
the jumper cables will reach, but never let the
vehicles touch. Make sure the jumper cables do not
have loose or missing insulation.
2. On both vehicles:
•Turn off engine and all lights and accessories,
except hazard warning flashers or work lights.
•Apply parking brake and shift selector lever to
position “P” (manual transmission to Neutral).
Important!
3. Clamp one end of the first jumper cable to the
positive (+) terminal of the discharged battery and
the other end to the positive (+) terminal of the
charged battery. Make sure the cable clamps do not
touch any other metal parts.
4. Clamp one end of the second jumper cable to the
grounded negative (–) terminal of the charged
battery and the final connection to a grounded
heavy metal bracket in the engine compartment or
on the engine of the disabled vehicle.Important!
5. Start engine of the vehicle with the charged battery
and run at high idle. Make sure the cables are not
on or near pulleys, fans, or other parts that will
move when the engine is started. Allow the
discharged battery to charge for a few minutes. Start
engine of the disabled vehicle in the usual manner.
6. After the engine has started, remove jumper cables
by exactly reversing the above installation
sequence, starting with the last connection made
first. When removing each clamp, make sure that it
does not touch any other metal while the other end
is still attached.
Note:
If engine does not run after several unsuccessful
starting attempts, have it checked at the nearest
authorized Mercedes-Benz Center.
Excessive unburned fuel may damage the catalytic
converter.
Page 260 of 290
257 Technical data
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index Layout of poly-V-belt drive
SLK 230 Kompressor
routing, belt I
The engine is equipped with two poly-V-belts.
1Crankshaft
2Air conditioner compressor
3Power steering pump
4Coolant pumpSLK 230 Kompressor
routing, belt II
For dimensions of the poly-V-belts, see page 260.
5Idler pulley
6Generator (alternator)
7Idler pulley
8Idler pulley
9Supercharger
P13.20-2007-26
9
6
8
7
4
1
5
32
5
32
9
6
8
4
1
7
P13.20-2008-26
Page 261 of 290
258 Technical data
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index
SLK 230 Kompressor
routing combined, belts I and II1Crankshaft
2Air conditioner compressor
3Power steering pump
4Coolant pump
5Idler pulley
6Generator (alternator)
7Idler pulley
8Idler pulley
9Supercharger
9
6
8
7
4
1
5
32P13.20-2009-26
Page 262 of 290
259 Technical data
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index SLK 320, SLK 32 AMG
belt routing1Automatic belt tensioner
2Crankshaft
3Air conditioner compressor
4Generator (alternator)
5Idler pulley
6Power steering pump
7Coolant pump
For dimensions of the poly-V-belt, see page 260.
6
5
1
2
3
7
4
Page 273 of 290

270 Fuels, coolants, lubricants etc. - capacities
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index
Gasoline additives
A major concern among engine manufacturers is carbon
build up caused by gasoline. Mercedes-Benz
recommends the use of only quality gasoline containing
additives that prevent the build up of carbon deposits.
After an extended period of using fuels without such
additives, carbon deposits can build up especially on the
intake valves and in the combustion area, leading to
engine performance problems such as:
•warm-up hesitation,
•unstable idle,
•knocking / pinging,
•misfire,
•power loss.
Do not blend other specific fuel additives with fuel.
They only result in unnecessary cost, and may be
harmful to the engine operation.
Damage or malfunctions resulting from poor fuel
quality or from blending specific fuel additives are not
covered by the Mercedes-Benz Limited Warranty.Coolants
The engine coolant is a mixture of water and
anticorrosion / antifreeze, which provides:
•corrosion protection,
•freeze protection,
•boiling protection (by increasing the boiling point).
The cooling system was filled at the factory with a
coolant providing freeze protection to approximately
-22°F (-30°C) and corrosion protection.
If the antifreeze mixture is effective to -22°F (-30°C), the
boiling point of the coolant in the pressurized cooling
system is reached at approximately 266°F (130°C).
The coolant solution must be used year round to provide
the necessary corrosion protection and increase in the
boil-over protection. You should have it replaced every
3years.
To provide the important corrosion protection, the
solution must be at least 45% anticorrosion / antifreeze
(equals a freeze protection to approx. - 22 °F [- 30 °C]). If
you use a solution that is more than 55% anticorrosion /
antifreeze (freeze protection to approx. - 49 °F [- 45°C]),