engine MERCEDES-BENZ R320 2008 W251 Manual PDF

235 Controls in detail
3-zone automatic climate control*
Deactivating
Press button; (page 224) again.
The indicator lamp on the button goes
out.
Residual heat and ventilation
With the engine switched off, it is possible
to continue to heat or ventilate the interior
for up to 30 minutes. This feature makes
use of the residual heat produced by the
engine.Activating
Switch off the ignition (page 39).
Press button9 (page 224).
The indicator lamp on the button
comes on.
Deactivating
Press button9.
The indicator lamp on the button goes
out.
iIf you manually set the temperature, air
volume or air distribution for the passenger side
or the rear passenger compartment when the
MONO setting is active, the MONO setting will
be switched off.
iHow long the system will provide heating
depends on

the coolant temperature

the battery voltage
Regardless of the temperature and air volume
set on the automatic climate control panel, an
interior temperature is aimed at by 72°F (22°C)
and the blower runs on low speed to protect the
vehicle battery.
iThe residual heat is automatically turned off:

when the ignition is switched on

after about 30 minutes

if the coolant temperature is too low

if the battery voltage drops

259 Controls in detail
Driving systems
Setting current speed
Accelerate or decelerate to the desired
speed.
Briefly lift the cruise control lever in
direction of arrow1 or depress in
direction of arrow2 (
page 258).
The current speed is set.
Remove your foot from the accelerator
pedal.
The cruise control is activated.
The currently set speed appears in the
status indicator of the multifunction
display:

USA only:
Cruise XXX Miles

Canada only:
Ñ
XXX Km/h
Canceling cruise control
There are several ways to cancel the cruise
control:
Step on the brake pedal.
The cruise control is canceled. The last
set speed is stored for later use.
or
Briefly push the cruise control lever in
direction of arrow3 (
page 258).
The cruise control is canceled. The last
set speed is stored for later use.
iOn uphill grades, the cruise control may not
be able to maintain the set speed. Once the
grade eases, the set speed will be resumed.
On downhill grades, the cruise control maintains
the set speed by braking with the vehicle’s
braking system. In addition, on longer downhill
grades the automatic transmission will down-
shift automatically.
iThe last stored speed is canceled when you
turn off the engine.
iThe cruise control switches off
automatically when

you step on the brake pedal

you depress the parking brake pedal
The cruise control switches off automatically and
an acoustic warning will sound when

the vehicle speed is below 20 mph
(30 km/h)

the ESP® is in operation

the ESP® is switched off with the ESP®
switch (
page 104)

the ESP® has switched off due to a
malfunction (
page 435)

you set the automatic transmission toN
while driving
Observe additional messages in the
multifunction display that may appear.

261 Controls in detail
Driving systems
Adjustment in 5 mph
(Canada: 10 km/h) increments
Briefly lift the cruise control lever up
past the resistance point in direction of
arrow1 (
page 258).
Release the cruise control lever.
The vehicle set speed increases in
increments of 5 mph
(Canada: 10 km/h).Setting a lower speed
You can reduce the set speed in two ways.Adjustment in 1 mph (Canada: 1 km/h)
increments
Briefly press the cruise control lever
down to the resistance point in direc-
tion of arrow2 (
page 258).
Release the cruise control lever.
The vehicle set speed decreases in in-
crements of 1 mph (Canada: 1 km/h).
iThe set speed value is increased in
5 mph (Canada: 10 km/h) increments each time
you lift the cruise control lever past the
resistance point.
iThe new speed is set and the vehicle will
accelerate. Keep in mind that it may take a brief
moment until the vehicle has reached the set
speed.
Warning!G
If you decrease the set vehicle speed, keep
in mind that it may take a brief moment until
the vehicle has reached the set speed.
Decrease the set vehicle speed to a value
that the prevailing road conditions and legal
speed limits permit. Otherwise, sudden and
unexpected acceleration of the vehicle
could cause an accident and/or serious
injury to you and others.
iWhen you use the cruise control lever to
decelerate, the brake system will automatically
brake the vehicle if the engine’s braking power
does not brake the vehicle sufficiently.
iThe set speed value is decreased in 1 mph
(Canada: 1 km/h) increments each time you
press the cruise control lever down to the resis-
tance point.

268 Controls in detail
Driving systems
1Setting current or higher speed
Adjustment in 1 mph increments (to
the resistance point) or 5 mph
increments (past the resistance point)
(Canada: 1 km/h or 10 km/h)
2Setting current or lower speed
Adjustment in 1 mph increments (to
the resistance point) or 5 mph
increments (past the resistance point)
(Canada: 1 km/h or 10 km/h)
3Deactivating Distronic
4Activating Distronic or resuming to last
set speedActivating Distronic
You can activate Distronic when the vehi-
cle speed is between 20 mph (30 km/h)
and 110 mph (180 km/h).
When Distronic is activated the standard
display in the multifunction display will
show a message such as
DISTRONIC 55 MPH.
If Distronic has not been activated after
pressing the cruise control lever, you will
see the message
DISTRONIC Off in the
multifunction display.
In the following cases you cannot activate
Distronic:

up to 2 minutes after starting the
engine

when you brake

when you have set the parking brake

when the automatic transmission is set
to positionP, R, or N

if the ESP® is switched off

if the ESP® has switched off due to a
malfunction
Setting the current speed
Accelerate or decelerate to the desired
speed.
Briefly lift the cruise control lever in
direction of arrow1 or depress in
direction of arrow2 (
page 268).
Distronic is activated and the current
speed is set.
The currently set speed appears in the
status indicator of the multifunction
display.
Remove your foot from the accelerator
pedal.

270 Controls in detail
Driving systems
Setting a lower speed
You can reduce the set speed in two ways.Adjustment in 1 mph (Canada: 1 km/h)
increments
Briefly press the cruise control lever
down to the resistance point in
direction of arrow2 (
page 268).
Release the cruise control lever.
The vehicle set speed decreases in in-
crements of 1 mph (Canada: 1 km/h).
Adjustment in 5 mph
(Canada: 10 km/h) increments
Briefly press the cruise control lever
down past the resistance point in
direction of arrow2 (
page 268).
Release the cruise control lever.
The vehicle set speed decreases in
increments of 5 mph
(Canada: 10 km/h).
Warning!G
If you decrease the set vehicle speed, keep
in mind that it may take a brief moment until
the vehicle has reached the set speed.
Decrease the set vehicle speed to a value
that the prevailing road conditions and legal
speed limits permit. Otherwise, sudden and
unexpected acceleration of the vehicle
could cause an accident and/or serious
injury to you and others.
iWhen you use the cruise control lever to
decelerate, the brake system will automatically
brake the vehicle if the engine’s braking power
does not brake the vehicle sufficiently.
iThe set speed value is decreased in
1 mph (Canada: 1 km/h) increments each time
you press the cruise control lever down to the
resistance point.
iThe set speed value is decreased in 5 mph
(Canada: 10 km/h) increments each time you
press the cruise control lever down past the
resistance point.
iThe new speed is set and the vehicle will
decelerate. Keep in mind that it may take a brief
moment until the vehicle has reached the set
speed.

271 Controls in detail
Driving systems
Setting to last stored speed
(“Resume” function)
Briefly pull the cruise control lever in
direction of arrow4 (
page 268).
The Distronic resumes to the last set
speed.
Remove your foot from the accelerator
pedal.
The last set speed or, if no speed is stored,
the current set speed appears in the
multifunction display for approximately
5seconds.Deactivating Distronic
There are several ways to deactivate the
Distronic system:
Step on the brake pedal.
or
Briefly tip the cruise control lever in
direction of arrow3 (
page 268).
Distronic will be deactivated. The last set
speed will be stored in memory.
Warning!G
The set speed stored in memory should only
be set again if prevailing road conditions
permit. Possible acceleration or decelera-
tion differences arising from returning to the
preset speed could cause an accident
and/or serious injury to you and others.
iThe following message appears in the multi-
function display for approximately 5 seconds:
DISTRONIC Off.
The last stored set speed is deleted when the
engine is turned off.
iThe Distronic switches off automatically
when

you step on the brake pedal

you depress the parking brake pedal
In this case, the Distronic speed segments in the
speedometer (
page 265) will go out.

the vehicle speed is below 20 mph
(30 km/h)

the ESP® is in operation

the ESP® is switched off with the ESP®
switch (
page 104)

the ESP® has switched off due to a
malfunction (
page 435)

you set the automatic transmission toN
while driving
The Distronic speed segments in the speedome-
ter (
page 265) will go out and an acoustic
warning will sound.

277 Controls in detail
Driving systems
1ADS switch
2Indicator lamp for SPORT setting
3Indicator lamp for COMF settingThe following settings are available:

AUTO (for normal driving situations)
Indicator lamps2 and3 are off.

SPORT (for sporty driving)
Indicator lamp2 comes on.

COMF (for comfort driving)
Indicator lamp3 comes on.
Start the engine (page 53).
Press ADS switch1 repeatedly until
the desired suspension tuning is
reached.Vehicle level control*
The vehicle level control automatically
regulates the ride height to

reduce fuel consumption

improve driving safety
The vehicle begins adjusting to the set
vehicle level as soon as the doors or
tailgate are

unlocked
or

opened or closed with the vehicle
unlocked
For major changes in vehicle level, the
engine must be running.
iThe setting is stored when you turn off the
engine.
iChanges to the vehicle level should be made
while the vehicle is moving. The vehicle will then
reach the set level as fast as possible.

279 Controls in detail
Driving systems
Raised level
Only choose the raised level when the road
conditions permit. Otherwise:

Fuel consumption may increase.

Handling characteristics of the vehicle
may be unfavorable.
Start the engine (page 53).The switch is located on the upper part of
the center console.
1Vehicle level control switch
2Indicator lamp
If indicator lamp2 is off:
Press switch1.
Indicator lamp2 flashes. The vehicle
adjusts to the raised level.
The following message appears in the
multifunction display while the level is
being set:When the raised level is reached, indicator
lamp2 comes on continuously and the
following message appears in the multi-
function display:
iYou can select the raised level at vehicle
speeds of up to 25 mph (40 km/h). At a higher
vehicle speed, the message
n
Level Selection Not Permitted
appears in the multifunction display.
iThe messages can be cleared by pressing
buttonæ orç on the multifunction steer-
ing wheel.

280 Controls in detail
Driving systems
Highway level
Close all doors and the tailgate.
Start the engine (page 53).
The switch is located on the upper part of
the center console.
1Vehicle level control switch
2Indicator lampIf indicator lamp2 is on:
Press switch1.
Indicator lamp2 flashes. The vehicle
adjusts to the highway level.
The following message appears in the
multifunction display while the level is
being set:When the highway level is reached, indica-
tor lamp2 goes out and the following
message appears in the multifunction dis-
play:
!Keep in mind that on rough or uneven roads,
adjusting the vehicle to a lower level may cause
the vehicle underbody to come in contact with
the road and result in damage to the vehicle
underbody. Always make sure the vehicle has
sufficient ground clearance before adjusting it
to a lower level.
iThe messages can be cleared by pressing
buttonæ orç on the multifunction steer-
ing wheel.
iThe vehicle level is set to highway level auto-
matically when the vehicle speed is exceeding
25 mph (40 km/h).

281 Controls in detail
Driving systems
Permanent four-wheel drive (4MATIC)*
Your vehicle is equipped with permanent
four-wheel drive (4MATIC). Both, the front
and rear axles, are powered at all times
when the vehicle is being operated. The
4MATIC improves traction in conjunction
with the ESP
® (page 101) and the
Electronic Traction System (
page 103).
Parktronic* (Parking assist)
Warning!G
If a drive wheel is spinning due to insuffi-
cient traction:

While driving off, apply as little throttle
as possible.

While driving, ease up on the accelera-
tor.

Adapt your speed and driving style to
the prevailing road conditions.
Failure to observe these guidelines could
cause the vehicle to skid.
The 4MATIC cannot prevent accidents re-
sulting from excessive speed.
!Operational or performance test must only
be conducted on a two-axle dynamometer. If
such tests are necessary, contact an authorized
Mercedes-Benz Light Truck Center. You could
otherwise seriously damage the brake system or
the transfer case which is not covered by the
Mercedes-Benz Limited Warranty.
!Because the ESP® operates automatically,
the engine and ignition must be shut off
(SmartKey in starter switch position0 or1 or
KEYLESS-GO* start/stop button in
position0or1) when testing the parking brake
on a brake test dynamometer and such testing
should be no longer than 10 seconds.
Active braking action through the ESP
® may
otherwise seriously damage the brake system
which is not covered by the Mercedes-Benz
Limited Warranty.
iIn winter operation, the maximum effective-
ness of the 4MATIC is only achieved with winter
tires (
page 398) or snow chains as required.
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 remains 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,
especially at times of snow and ice, see
“Cleaning the Parktronic* system sensors”
(
page 408).
Interference caused by other ultrasonic
signals (e.g. working jackhammers, car
wash, or the air brakes of trucks) can cause
the system to send erratic indications, and
should be taken into consideration.