Mercedes-Benz 2008 R 320 CDI 4MATIC Operator's Manual page 260

Setting current speed
Accelerate or decelerate to the desired
speed.
Briefly lift the cruise control lever in
direction of arrow 1 or depress in
direction of arrow 2 ( 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
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On 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.
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 arrow 3 ( page 258).
The cruise control is canceled. The last
set speed is stored for later use.
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The last stored speed is canceled when you
turn off the engine.
Controls in detail
Driving systems
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The 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 to N
while driving
Observe additional messages in the
multifunction display that may appear.
®
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