2005 MERCEDES-BENZ E320CDI brakes

242 Controls in detailDriving systemsDeactivating Distronic
There are several ways to deactivate the
Distronic system:
Briefly tip the cruise control lever in the
direction of arrow3 (
page 239).
or

Step on the brake pedal.
Distronic will be deactivated. The last
speed set will be stored in memory.Distronic deactivates automatically when:


you set the parking brake


you drive slower than 25 mph
(40 km / h)


the ESP is active (
page 87) or you de-
activate the ESP


you move the transmission selector le-
ver into positionN
A si gnal wi ll s ound. T he
Distronic off

message appears in the multifunction
display for approximately five seconds.Setting the following distance in
Distronic
You can set the specified following dis-
tance for Distronic by varying the time set-
ting between 1.0 and 2.0 seconds. Using
this time setting and the current speed of
your vehicle, Distronic calculates and sets
the required following distance to the vehi-
cle ahead. The set distance will be shown
in the multifunction display field.
The thumbwheel for making the time set-
ting is located on the lower section of the
center console.
iThe following message will appear in
the multifunction display for approxi-
mately five seconds:
Distronic off
.
The last stored speed is deleted when
you turn off the engine.
Warning!
G
Distronic switches off and releases the
brakes when the vehicle decelerates below
the minimum speed of approximately
25 mph (40 km / h) by operation of the sys-
tem. At that time the driver must apply the
brakes in order to reduce vehicle speed fur-
ther or bring it to a stop.
Warning!
G
It is up to the driver to exercise discretion to
select the appropriate setting given road
conditions, traffic, driver’s preferred driving
style and applicable laws and driving recom-
mendations for safe following distance.

243 Controls in detail
Driving systems
1Distance warning function on/off
switch
2Control lamp
3Thumbwheel for setting distance
Increasing distance
Increasing the distance setting tells
Distronic to maintain a greater following
distance to the vehicle ahead.
Turn thumbwheel3 towards¯.Decreasing distance
Decreasing the distance setting tells
Distronic to maintain a shorter following
distance to the vehicle ahead.

Turn thumbwheel3 towards®.
Distance warning function
When Distronic is deactivated, this func-
tion will continue to warn you when recog-
nizing a stationary obstacle or a slower
vehicle moving in the vehicle’s path and
the danger of a collision exists:


The distance warning lampl in the
instrument cluster comes on.


An intermittent warning sounds.
If these warnings are issued, you must
brake manually to maintain a safe distance
and avoid a collision with the vehicle
ahead.
When pressing the brake pedal, the warn-
ing sound stops. The warning sound also
stops when the distance to the vehicle ahead is sufficient again without applying
the brake pedal. In this case the distance
warning lamp also extinguishes.
Warning!
G
If the DTR warning lampl in the instru-
ment cluster comes on while driving and/or
an intermittent warning sounds, immediate
attention on the part of the driver is re-
quired. As required by the traffic situation,
apply the brakes and navigate around a pos-
sible obstacle. However, do not drive by re-
lying on the distance warning function, as
this will result in an emergency braking ap-
plication. Especially depending on road sur-
face conditions and driver reaction, this will
not always enable you to avoid a collision.iComplex driving situations are not al-
ways fully recognized by Distronic. This
could result in wrong or missing dis-
tance warnings.

250 Controls in detailDriving systemsParktronic system (Parking assist)*
The Parktronic system is an electronic aid
designed to assist the driver during park-
ing maneuvers. It visually and audibly indi-
cates the relative distance between the
vehicle and an obstacle.
The Parktronic system is automatically ac-
tivated when you switch on the ignition, re-
lease the parking brake, and placed the
gear selector lever in positionD,R,orN.
The Parktronic system deactivates at
speeds over approximately 11 mph
(18 km/h). At lower speeds the Parktronic
system turns on again.
The Parktronic system also deactivates
when you place the gear selector lever in
positionP or depress the parking brake
pedal.The Parktronic system monitors the sur-
roundings of your vehicle with six sensors
in the front bumper and four sensors in the
rear bumper.
1Sensors in the front bumper
Range of the sensors
To function properly, the sensors must be
free of dirt, ice, snow and slush. Clean the
sensors regularly, being careful not to
scratch or damage the sensors, see
“Cleaning the Parktronic system* sensors”
(
page 351).
Warning!
G
Parktronic is a supplemental system. It is
not intended to, nor does it replace, the
need for extreme care. The responsibility
during parking and other critical maneuvers
always rests with the driver.
Special attention must be paid to objects
with smooth surfaces or low silhouettes
(e.g. trailer couplings, painted posts, or road
curbs). Such objects may not be detected by
the system and can damage the vehicle.
The operational function of the Parktronic
system can be affected by dirty sensors, es-
pecially at times of snow and ice, see
“Cleaning the Parktronic system* sensors”
(page 351).
Interference caused by other ultrasonic sig-
nals (e.g. working jackhammers, car wash or
the air brakes of trucks) can cause the sys-
tem to send erratic indications, and should
be taken into consideration.
Warning!
G
Make sure no persons or animals are in the
area in which you are maneuvering. You
could otherwise injure them.

251 Controls in detail
Driving systems
Front sensors
Rear sensorsMinimum distance
If the system detects an obstacle in this
range, all the distance warning segments
illuminate and you hear a warning signal. If
the obstacle is closer than the minimum
distance, the actual distance might no
longer be indicated by the system.Center
approx. 40 in (100 cm)
Corners
approx. 24 in (60 cm)
Center
approx. 48 in (120 cm)
Corners
approx. 32 in (80 cm)
!During parking maneuvers, pay special
attention to objects located above or
below the height of the sensors (e.g.
planters or trailer hitches). The
Parktronic system will not detect such
objects at close range and damage to
your vehicle or the object may result.
Ultrasonic signals from outside sourc-
es (e.g. truck air brakes, car wash or
jackhammers) may impair the opera-
tion of the Parktronic system.
Center
approx. 8 in (20 cm)
Corners
approx. 6 in (15 cm)

288 OperationDriving instructionsPower assistance
Brakes
Warning!
G
The brake system requires electrical energy
for operation.
A malfunction in the vehicle’s power supply
or electrical system may impair brake sys-
tem operation and switch it into its emer-
gency operation mode. In such a case, the
red brake warning lamp (
page 358) and
warning messages in the instrument cluster
(
page 367) come on while driving. To
brake, the driver must then apply signifi-
cantly greater brake pedal pressure and de-
press the pedal much further to obtain the
expected braking effect. If necessary, apply
full pressure to the brake pedal. Brakes may
only be applied to the front wheels. Stop-
ping distance is increased!
If there is a malfunction in the SBC brake
system, we recommend that the vehicle be
transported with all wheels off the ground
using flatbed or appropriate wheel lift/dolly
equipment. A tow bar must be used if cir-
cumstances do not permit the use of the
recommended towing methods and the ve-
hicle requires towing with all four wheels on
the ground. Towing the vehicle with all four
wheels on the ground is only permissible for
distances up to 30 miles (50 km) and at a
speed not to exceed 30 mph (50 km/h). For
more information, refer to “Towing the vehi-
cle” (
page 439). For more information,
see “SBC brake system” (
page 90).
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 ve-
hicle.
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.

289 Operation
Driving instructions
To 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 sub-
jected to moderate loads, you should occa-
sionally 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 clus-
ter stays on, there is a malfunction in the
SBC brake system (
page 90) or 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 res-
ervoir.
Have the brake system inspected by quali-
fied technicians immediately. Contact an
authorized Mercedes-Benz Center.
All checks and service work on the brake
system should be carried out by qualified
technicians only. Contact an authorized
Mercedes-Benz Center.
Only install brake pads and brake fluid rec-
ommended by Mercedes-Benz.
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.
!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 87).
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.
Be certain to read and observe the warning
notices on brake pad replacement
(page 380).!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 pre-
vent overheating of the brakes and re-
duces brake pad wear.

290 OperationDriving instructionsDriving 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 oper-
ating temperature has been reached.
When starting off on a slippery surface, do
not allow a drive wheel to spin for an ex-
tended 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
Tires
!Simultaneously depressing the acceler-
ator pedal and applying the brake re-
duces 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 position P.
When parking on hills, always set the
parking brake and turn front wheel
against road curb.Warning!
G
Do not park this vehicle in areas where com-
bustible 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 selector lever to positionP.


Slowly release brake pedal.


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


Turn the SmartKey in the starter switch
to position0 and remove the SmartKey
from the starter switch, or press
KEYLESS-GO* start/stop button (vehi-
cles with KEYLESS-GO*).


Take the SmartKey or the SmartKey with
KEYLESS-GO* with you and lock vehicle
when leaving.
Warning!
G
If you feel a sudden significant vibration or
ride disturbance, or you suspect that possi-
ble damage to your vehicle has occurred,
you should turn on the hazard warning flash-
ers, carefully slow down, and drive with cau-
ti o n t o an a r ea wh ic h is a s a fe d is ta n c e fr o m
the road.

291 Operation
Driving instructions
Treadwear indicators (TWI) are required by
law. These indicators are located in six
places on the tread circumference and be-
come visible at a tread depth of approxi-
mately
1/16 i n ( 1 . 6 m m ) , a t w h i c h p o i n t t h e
tire is considered worn and should be re-
placed.
The treadwear indicator appears as a solid
band across the tread.
Specified tire inflation pressures must be
maintained. This applies particularly if the
tires are subjected to high loads (e.g. high
speeds, heavy loads, high ambient temper-
atures).
Hydroplaning
Depending on the depth of the water layer
on the road, hydroplaning may occur, even
at low speeds and with new tires. Reduce
vehicle speed, avoid track grooves in the
road and apply brakes cautiously in the
rain.
Inspect the tires and the vehicle underbody
for possible damage. If the vehicle or tires
appear unsafe, have it towed to the nearest
Mercedes-Benz Center or tire dealer for re-
pairs.
Warning!
G
Although the applicable federal motor vehi-
cle safety laws consider a tire to be worn
when the treadwear indicators (TWI) be-
come visible at approximately
1/16in
(1.6 mm), we recommend that you do not al-
low your tires to wear down to that level. As
tread depth approaches
1/8in (3 mm), the
adhesion properties on a wet road are
sharply reduced.
Depending upon the weather and/or road
surface (conditions), the tire traction varies
widely.
Warning!
G
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle. You
may lose control of the vehicle. Continued
driving with a flat tire or driving at high
speed with a flat tire will cause excessive
heat build-up and possibly a fire.