2004 MERCEDES-BENZ C320 Brake system

146 Controls in detailAutomatic transmission*
Program mode selector switch
The program mode selector switch is
located on the lower part of the center
console.
1Program mode selector switch
S Sport For standard driving
C Comfort For comfort driving
!Coasting the vehicle, or driving for any
other reason with gear selector lever
inN can result in transmission damage
that is not covered by the
Mercedes-Benz Limited Warranty.Warning!
G
Getting out of your vehicle with the gear
selector lever not fully engaged in positionP
is dangerous. Also, positionP alone is not
intended to or capable of preventing your
vehicle from moving, possibly hitting people
or objects.
Always set the parking brake in addition to
shifting to positionP (
page 50).
When parked on an incline, turn the front
wheels towards the road curb.
Do not park 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.
Warning!
G
When leaving the vehicle, always remove the
SmartKey from the starter switch, take it
with you 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
positionP, which could result in an accident
and/or serious personal injury.
!Never change the program mode when
the gear selector lever is out of
positionP. This could result in a
change of driving characteristics for
which you may not be prepared.

206 Controls in detailDriving systems
Driving systemsThe driving system of your vehicle is
described on the following pages:

Cruise control, with which the vehicle
can maintain a preset speed
For information on the BAS, ABS and ESP
driving systems, see “Driving safety sys-
tems” (
page 72).
Cruise control
Cruise control automatically maintains the
speed you set for your vehicle.
Use of cruise control is recommended for
driving at a constant speed for extended
periods of time. You can set or resume
cruise control at any speed over 20 mph
(30 km/h).
The cruise control function is operated by
means of the cruise control lever.
The cruise control lever is the uppermost
lever found on the left-hand side of the
steering column (
page 20).
Warning!
G
Cruise control is a convenience system de-
signed to assist the driver during vehicle op-
eration. The driver is and must remain at all
times responsible for the vehicle speed and
for safe brake operation.
Only use cruise control if the road, traffic
and weather conditions make it advisable to
travel at a steady speed.

The use of cruise control can be danger-
ous on winding roads or in heavy traffic
because conditions do not allow safe
driving at a steady speed.


The use of cruise control can be danger-
ous on slippery roads. Rapid changes in
tire traction can result in wheel spin and
loss of control.


Deactivate cruise control when driving
in fog.
The “Resume” function should only be oper-
ated if the driver is fully aware of the previ-
ously set speed and wishes to resume this
particular preset speed.

207 Controls in detail
Driving systems
1Set current or higher speed
2Set current or lower speed
3Cancel cruise control
4Resume at last set speed
Setting current speed
Accelerate or decelerate to the desired
speed.

Briefly lift1 or depress2 cruise
control lever.
The current speed is set.

Remove your foot from the accelerator
pedal.
Cruise control is activated.Canceling cruise control
There are several ways to cancel cruise
control:

Step on the brake pedal.
or

Briefly push cruise control lever to
position3.
Cruise control will be canceled. The
last speed set will be stored for later
use.iOn uphill or downhill grades, cruise
control may not be able to maintain the
set speed. Once the grade eases, the
set speed will be resumed.
!Vehicles with automatic transmission:
Moving gear selector lever to
positionN while driving also cancels
cruise control. However, the gear
selector lever should not be moved to
positionN while driving except to coast
when the vehicle is in danger of skid-
ding (e.g. on icy roads).iVehicles with manual transmission:
The set cruise controlled speed is
switched off when declutching exceeds
four seconds during downshifting a
gear.iThe last stored speed is canceled when
you turn off the engine.

208 Controls in detailDriving systemsSetting a higher speed
Lift cruise control lever to position1
and hold it up until the desired speed is
reached.

Release cruise control lever.
The new speed is set.
Setting a lower speed

Depress cruise control lever to
position2 and hold it down until the
desired speed is reached.

Release cruise control lever.
The new speed is set.Fine adjustment in 1 mph
(Canada: 1 km/h) increments
Faster

Briefly tip cruise control lever in the
direction of arrow1.
Slower

Briefly tip cruise control lever in the
direction of arrow2.Setting to last stored speed (“Resume”
function)

Briefly push cruise control lever to
position4.
The cruise control will resume the last
set speed.

Remove your foot from the accelerator
pedal.
iDepressing the accelerator pedal does
not deactivate cruise control. After
brief acceleration (e.g. for passing),
cruise control will resume the last
speed set.
iVehicles with automatic transmission:
When you use the cruise control lever
to decelerate, the transmission will
automatically downshift if the engine’s
braking power does not brake the
vehicle sufficiently.
Warning!
G
The speed stored in memory should only be
set again if prevailing road conditions per-
mit. Possible acceleration or deceleration
differences arising from returning to preset
speed could cause an accident and/or seri-
ous injury to you and others.

239 Operation
Driving instructions
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 infla-
tion pressures.


Remove unnecessary loads.


Remove roof rack when not in use.


Allow engine to warm up under low
load use.


Avoid frequent acceleration and decel-
eration.


Have all maintenance work performed
at the intervals specified in the Service
Booklet and as required by the FSS.
Contact your 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
PedalsPower assistance
Warning!
G
Drinking and driving and/or taking drugs
and driving are very dangerous combina-
tions. Even a small amount of alcohol or
drugs can affect your reflexes, perceptions
and judgement.
The possibility of a serious or even fatal
accident are greatly increased when you
drink or take drugs and drive.
Do not drink or take drugs and drive or allow
anyone to drive who has been drinking or
taking drugs.
Warning!
G
Keep driver’s foot area clear at all times.
Objects stored in this area may impair pedal
movement.Warning!
G
With the engine not running, there is no
power assistance for the brake and steering
systems. In this case, it is important to keep
in mind that a considerably higher degree of
effort is necessary to brake and steer the
vehicle.

240 OperationDriving instructionsBrakesTo help prevent brake disk corrosion after
driving on wet road surfaces (particularly
salted roads), it is advisable to brake the
vehicle with considerable force prior to
parking. The heat generated serves to dry
the brakes.
If your brake system is normally only
subject to moderate loads, you should
occasionally test the effectiveness of the
brakes by applying above-normal braking
pressure at higher speeds. This will also
enhance the grip of the brake pads.
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
immediately. Contact your authorized
Mercedes-Benz Center.
All checks and service work on the brake
system should be carried out by qualified
technicians only. Contact your authorized
Mercedes-Benz Center.
Only install brake pads and brake fluid
recommended by Mercedes-Benz.Warning!
G
After driving in heavy rain for some time
without applying the brakes or through wa-
ter deep enough to wet brake components,
the first braking action may be somewhat
reduced and increased pedal pressure may
be necessary to obtain expected braking ef-
fect. 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 effec-
tiveness. It may not be possible to stop the
vehicle in sufficient time to avoid an acci-
dent.
!Be very careful not to endanger other
road users when you apply the brakes.
Refer to the description of the Brake
Assist System (BAS) (
page 73).
Warning!
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.

241 Operation
Driving instructions
After hard braking, it is advisable to drive
on for some time, rather than immediately
parking, so that the air stream will cool
down the brakes faster.Driving off
Apply the 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 a 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.
Parking
!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.
!Simultaneously depressing the
accelerator pedal and applying the
brake reduces engine performance and
causes premature brake and drivetrain
wear.!Set the parking brake whenever park-
ing or leaving the vehicle. In addition,
move gear selector lever to positionP
(manual transmission: first or reverse
gear).
When parking on hills, always turn front
wheels towards the road curb.
Warning!
G
Do not park 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.
To reduce the risk of personal injury as a re-
sult of vehicle movement, before turning off
the engine and leaving the vehicle always:

Keep right foot on brake pedal.


Firmly depress parking brake pedal.


Move the gear selector lever to
positionP (manual transmission: first or
reverse gear).


Slowly release brake pedal.


When parked on an incline, turn front
wheels towards the road curb.


Turn the SmartKey to starter switch
position0 and remove.


Take the SmartKey with you and lock
vehicle when leaving.

251 Operation
At the gas station
Check regularly and before a long trip
1Coolant level
For more information on coolant, see
“Coolant level” (
page 257).
2Brake fluid (fuse box cover removed)
Removing fuse box cover
(
page 333).
3Windshield washer and headlamp
cleaning system*
For more information on filling up the
washer reservoir, see “Windshield
washer system and headlamp cleaning
system*” (
page 259).Engine oil level
For more information on engine oil level,
see “Engine oil” (
page 253).
Opening hood (
page 252).
Vehicle lighting
Check function and cleanliness. For more
information on replacing light bulbs, see
“Replacing bulbs” (page 310).
Exterior lamp switch (page 102).
Tire inflation pressure
More information on tire inflation pressure
(
page 261).
!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 275).