engine MERCEDES-BENZ CLK430 CABRIOLET 2003 C208 Service Manual

193 Automatic transmission
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Stopping
For brief stops, e.g. at traffic lights, leave the
transmission in gear and hold vehicle with the service
brake.
For longer stops with the engine idling, shift into “N”
or “P” and hold the vehicle with the service brake.
When stopping the vehicle on an uphill gradient, do not
hold it with the accelerator, use the brake. This avoids
unnecessary transmission heat build up.
Maneuvering
To maneuver in tight areas, e.g. when pulling into a
parking space, control the vehicle speed by gradually
releasing the brakes. Accelerate gently and never
abruptly step on the accelerator.
To rock a vehicle out of soft ground (mud or snow),
alternately shift from forward to reverse, while applying
slight partial throttle.Rocking a vehicle free in this manner may cause the
ABS or traction system malfunction indicator lamp to
come on. Turn off and restart the engine to clear the
malfunction indication.
Wa r n i n g !
Getting out of your vehicle with the selector lever
not fully engaged in position “P” is dangerous.
Also, when parked on an incline, position “P” alone
may not prevent your vehicle from moving,
possibly hitting people or objects.Always set the parking brake in addition to shifting
to position “P”, see page 200 for parking brake. When parked on an incline, also turn front wheel
against curb.Wa r n i n g !
When leaving the vehicle, always remove the
electronic key from the steering lock, and lock the
vehicle. Do not leave children unattended in the
vehicle, or with access to an unlocked vehicle.
Children could move the gear selector lever from
position “P”, which could result in an accident
and/or serious personal injury.

195 Automatic transmission
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Dependent on the program mode selector switch
position “S” or “W” the maximum speed in the
reverse gear is different. However, it is not
possible to change the program mode while in
reverse.
Neutral
No power is transmitted from the engine to the
drive axle. When the brakes are released, the
vehicle can be moved freely (pushed or towed). Do
not engage “N” while driving except to coast
when the vehicle is in danger of skidding (e.g. on
icy roads, see winter driving instructions on
page 207).
Important!
Coasting the vehicle, or driving for any other
reason with selector lever in “N” can result in
transmission damage that is not covered by the
Mercedes-Benz Limited Warranty.
The transmission automatically upshifts through
5th gear. Position “D” provides optimum driving
characteristics under all normal operating
conditions.Gear selection for special circumstances
The transmission gear ranges for special circumstances
can be selected by pressing the selector lever to the
right or the left with the selector lever in position “D”.
The gear range currently selected is indicated in the
instrument cluster display.
Briefly press selector lever in the ç direction:
The transmission downshifts, one gear at a time, in the
order “4”, “3”, “2”, “1”.
Press and hold selector lever in the ç direction:
The selector lever position display will switch to the
gear range currently selected by the automatic
transmission.
The transmission will only shift down one gear if the
gear range currently selected has already shifted to its
highest possible gear.
Briefly press selector lever in the æ direction:
The transmission will shift from the current gear range
to the next higher gear range as permitted by the shift
program.

196 Automatic transmission
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Press and hold selector lever in the æ direction:
The transmission will shift from the current gear
directly to gear range “D”.
Important!
With transmission in gear range “D”, “4” or “3”,
upshifting from 1st to 2nd to 3rd gear is delayed
depending on vehicle speed and engine temperature.
This allows the catalytic converter to heat up more
quickly to operating temperatures.During the brief warm-up period this delayed upshift
and increased engine noise might be perceived as a
malfunction. However, neither the engine nor
transmission are negatively affected by this mode of
operation.
The delayed upshift is effective with vehicle speeds
below 31 mph (50 km/h) at partial throttle and engine
temperatures below 95
°F (35
°C).
To avoid overrevving the engine when the selector lever
is m ove d to a lower gear range , t he tran smi ss ion will n ot
shift to a lower gear, if the engine's max. speed would be
exceeded. In this case there will be no downshift, even
when the vehicle speed reaches the engine’s RPM limit
of that gear, e.g. by applying the service brakes.
To prevent the engine from laboring at low RPM when
driving uphill gradients or with your vehicle heavily
loaded, the automatic transmission will downshift when
necessary to maintain engine RPM within the best
torque range.
Wa r n i n g !
On slippery road surfaces, never downshift in order
to obtain braking action. This could result in drive
wheel slip and reduced vehicle control. Your
vehicle’s ABS will not prevent this type of loss of
control.

197 Automatic transmission
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Gear ranges:
Upshift through 4th gear only. Suitable for
performance driving.
Upshift through 3rd gear only. Suitable for
moderately steep hills. Since the transmission
does not shift higher than 3rd gear, this gear
selection will allow use of the engine’s braking
power downhill.Upshift through 2nd gear only. For driving in
mountainous regions or under extreme operating
conditions. This gear selection will allow use of
the engine’s braking power when descending
steep grades.
Use this position, which makes maximum use of
the engine’s braking effect, while descending
very steep or lengthy downgrades and only at
speeds below 40 mph (60 km/h).

198 Automatic transmission
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Program mode selector switch
The transmission is provided with a selector switch (1)
for Standard “S” and Winter/Wet (snow and ice) “W”
program modes.
SStandard mode
Press switch on symbol “S”. Use this mode for all
regular driving.
The vehicle starts out in 1st gear.Accelerator Operation:
Fast on = depressing the accelerator pedal quickly
(not into kickdown position) while driving
continuously, rather than depressing the
accelerator pedal in the usual manner, will cause
the automatic transmission to shift down into a
lower gear. This gear shifting process is
dependent on the current vehicle speed.
Fast off = there will be no upshift when releasing
the accelerator pedal quickly, e.g. using the
engine’s braking power during performance
driving.
WWinter/Wet (snow and ice) mode
Press switch on symbol “W”. The vehicle starts
out in 2nd gear, except with selector lever in 1st
gear, or with accelerator pedal in kick-down
position.
The “W” mode helps to improve traction and
driving stability of the vehicle.
The gear shifting process occurs at lower vehicle
and engine speeds than in the “S” program mode.
1

199 Automatic transmission
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Caution!
Never change the program mode when the selector lever
is out of position “P”. It could result in a change of
driving characteristics for which you may not be
prepared.
Important!
Always be certain of the program mode selected since
the vehicle driving characteristics change with the
selection of the program mode.
Dependent on the program mode selector switch
position “S” or “W” and the gear selector lever in
position “R”, the ratio of power transmission changes.
Emergency operation (Limp home mode)
If vehicle acceleration worsens or the transmission no
longer shifts, the transmission is most likely operating
in Limp home mode which engages when there is a
malfunction of the transmission. This condition may be
accompanied by the “CHECK ENGINE” malfunction
indicator lamp in the instrument cluster coming on.In this mode only the 2nd gear or reverse gear can be
activated.
To engage 2nd gear or reverse:
1. Stop the vehicle.
2. Move selector lever to position “P”.
3. Turn off the engine.
4. Wait approx. 10 seconds.
5. Restart the engine.
6. Move selector lever to position “D” (for 2nd gear), or
move selector lever to position “R” (for reverse gear).
Have the transmission checked at your authorized
Mercedes-Benz Center as soon as possible.

201 Driving instructions
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Driving instructions
Drive sensibly – save fuel
Fuel consumption, to a great extent, depends on driving
habits and operating conditions.
To save fuel you should:
•keep tires at the recommended inflation pressures,
•remove unnecessary loads,
•allow engine to warm up under low load use,
•avoid frequent acceleration and deceleration,
•have all maintenance work performed at regular
intervals by an authorized Mercedes-Benz Center.
Fuel consumption is also increased by driving in cold
weather, in stop-and-go traffic, on short trips and in hilly
country.Drinking and driving
Ped al s
Wa r n i n g !
Drinking and driving and/or taking drugs and
driving can be a very dangerous combination. Even
a small amount of alcohol or drugs can affect your
reflexes, perceptions and judgement.The possibility of a serious or even fatal accident is
sharply increased when you drink or take drugs
and drive.Please don’t drink or take drugs and drive or allow
anyone to drive after drinking or taking drugs.Wa r n i n g !
Keep driver’s foot area clear at all times. Objects
stored in this area may impair pedal movement.

202 Driving instructions
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Power assistance
BrakesExcessive use of salt and other snow melting chemicals
spread on roads during the winter months may cause a
build up of moisture or residue to form on the braking
components. This build up or residue could cause light
corrosion of the braking components if the vehicle is
parked with the brakes cold. Apply steady and even
braking pressure when stopping the vehicle to warm up
and dry the brake components.
Important!
Please pay attention to the function of the brake assist
system (BAS), see page 212.
If the parking brake is released and the brake warning
lamp in the instrument cluster stays on, the brake fluid
level in the reservoir is too low.
Brake pad wear or a leak in the system may be the
reason for low brake fluid in the reservoir.
Have the brake system inspected at an authorized
Mercedes-Benz Center immediately.
Wa r n i n g !
When the engine is not running, the brake and
steering systems are without power assistance.
Under these circumstances, a much greater effort is
necessary to stop or steer the vehicle.Wa r n i n g !
After driving in heavy rain for some time without
applying the brakes or through water deep enough
to wet brake components or salty road conditions,
the first braking action may be somewhat reduced
and increased pedal pressure may be necessary to
obtain expected braking effect. Be sure to maintain
a safe distance from vehicles in front.Resting your foot on the brake pedal will cause
excessive and premature wear of the brake pads.It can also result in the brakes overheating thereby
significantly reducing their effectiveness. It may
not be possible to stop the vehicle in sufficient time
to avoid an accident.

203 Driving instructions
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index All checks and service work on the brake system should
be carried out by an authorized Mercedes-Benz Center.
Install only brake pads and brake fluid recommended by
Mercedes-Benz.
Caution!
When driving down long and steep grades, relieve the
load on the brakes by shifting into a lower gear to use
the engine’s braking power. This helps prevent
overheating of the brakes and reduces brake pad wear.
After hard braking, it is advisable to drive on for some
time, rather than immediately parking, so the air stream
will cool down the brakes faster.Driving off
Apply the service brakes to test them briefly after
driving off. Perform this procedure only when the road
is clear of other traffic.
Warm up the engine smoothly. Do not place full load on
the engine until the operating temperature has been
reached.
When starting off on a slippery surface, do not allow one
drive wheel to spin for an extended period with the ESP
switched off. Doing so may cause serious damage to the
drive train which is not covered by the Mercedes-Benz
Limited Warranty.
Wa r n i n g !
If other than recommended brake pads are
installed, or other than recommended brake fluid
is used, the braking properties of the vehicle can be
degraded to an extent that safe braking is
substantially impaired. This could result in an
accident.

204 Driving instructions
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Parking
Important!
It is advisable to set the parking brake whenever
parking or leaving the vehicle. In addition, move
selector lever to position “P”.
When parking on hills, always set the parking brake.Tires
Tread wear indicators (TWI) are required by law. These
indicators are located in six places on the tread
circumference and become visible at a tread depth of
approximately
1/16in (1.5 mm), at which point the tire is
considered worn and should be replaced.
The tread wear indicator appears as a solid band across
the tread.
Wa r n i n g !
To reduce the risk of personal injury as a result of
vehicle movement, before
turning off the engine
and leaving the vehicle, always:
1. Keep right foot on the service brake pedal.
2. Firmly depress parking brake pedal.
3. Move the selector lever to position “P”.
4. Slowly release the service brake pedal.
5. Turn front wheels towards the road curb.
6. Turn the electronic key to steering lock
position 0 and remove.
7. Take the electronic key and lock vehicle when
leaving.
Wa r n i n g !
If you feel a sudden significant vibration or ride
disturbance, or you suspect that possible damage to
your vehicle has occurred, you should turn on the
hazard warning flashers, carefully slow down, and
drive with caution to an area which is a safe
distance from the roadway.Inspect the tires and under the vehicle for possible
damage. If the vehicle or tires appear unsafe, have
it towed to the nearest Mercedes-Benz Center or
tire dealer for repairs.