2008 MERCEDES-BENZ R320 keyless

502 Practical hints
Bleeding the fuel system (diesel engine only)
Driving the vehicle until the fuel tank is
empty is not recommended. Otherwise, air
may be sucked into the fuel system. If this
happens, the? malfunction indicator
lamp (USA only) or the ± malfunction
indicator lamp (Canada only) comes on
and the engine may not start immediately
after refueling the vehicle.
After refueling:
Make sure the automatic transmission
is set toP.
The gear position indicator in the multi-
function display should be on
P.
Do not depress the accelerator.
Turn the SmartKey in the starter switch
to position 2 for at least 10 seconds
(
page 40).
Return the SmartKey in the starter
switch to position 0 (
page 40).
Turn the SmartKey in the starter switch
to position 3 (
page 41) and hold it
there for a maximum of 40 seconds or
until the engine runs surge-free.
If the engine does not start:
Wait for approximately 2 minutes.
Turn the SmartKey in the starter switch
to position 3 (
page 41) and hold it
there for a maximum of 40 seconds or
until the engine runs surge-free.
If the engine still does not start, do not
make any further attempts to start the
engine. Contact an authorized
Mercedes-Benz Light Truck Center or call
Roadside Assistance (
page 325).iVehicles with KEYLESS-GO*: If necessary,
remove the KEYLESS-GO start/stop button from
the starter switch (
page 41).iWhen the? malfunction indicator lamp
(USA only) or the ± malfunction indicator
lamp (Canada only) has been illuminated for the
above condition, it will remain illuminated until
the engine was cycled on and off four times in a
row.

505 Practical hints
Battery
Disconnecting, removing, reinstalling
and reconnecting the battery
Step 1 (Disconnecting)
Set the automatic transmission to
positionP (
page 192).
Firmly depress the parking brake
(
page 65).
Turn off the engine (page 66).
Leave the ignition switched on
(
page 39).
!Never loosen or detach battery terminal
clamps while the engine is running or the
SmartKey is in the starter switch. Otherwise the
alternator and other electronic components
could be severely damaged.
Have the battery checked regularly by an autho-
rized Mercedes-Benz Light Truck Center.
Contact your authorized Mercedes-Benz Light
Truck Center for further information.
Warning!G
Do not place metal objects on the battery as
this could result in a short circuit.
Use leak-proof battery only to avoid the risk
of acid burns in the event of an accident.
Warning!G
Disconnecting, removing, reinstalling and
reconnecting the battery is a complicated
and technically demanding procedure that
also requires safety precautions to avoid the
risk of injury. We strongly recommend that it
be performed by a qualified technician or an
authorized Mercedes-Benz Light Truck
Center only. Please read the instructions
fully before beginning operation and only
undertake it if you feel fully capable of
performing all of the tasks involved as
described in these instructions. Observe all
safety instructions and precautions when
handling automotive batteries
(
page 503). Performing the tasks involved
incorrectly can cause damage to the vehicle
and impair the operating safety of the
vehicle, and/or cause severe injury to you
or others.
iWith a disconnected battery you will no
longer be able to turn the SmartKey in the
starter switch and pressing the KEYLESS-GO*
start/stop button will have no effect.
iIf your battery is discharged, the vehicle
must be jump started (
page 511) using the
jump start contacts in the engine compartment,
or an accessory battery charge unit* approved
by Mercedes-Benz must be connected using the
jump start contacts in the engine compartment
(see separate instructions for the accessory
battery charge unit*) before any of the following
steps can be performed. If the battery cannot be
jumped or charged, please contact an autho-
rized Mercedes-Benz Light Truck Center.


507 Practical hints
Battery
Switch off the ignition (page 40).
Remove the SmartKey from the starter
switch.
Vehicles with KEYLESS-GO*:
Make sure the vehicle’s on-board
electronics have status 0.
After turning off the engine with the
KEYLESS-GO start/stop button,
with the driver’s door closed, the
starter switch is in position1.
With the driver’s door opened, the
starter switch is set to position0,
same as SmartKey removed from
starter switch (
page 41).Step 3 (Disconnecting)
4Seat rail, rear
5Seat rail cover, rear
Pull seat rail cover 5 away from seat
rail 4 on both sides as indicated by
arrows.
Pull off seat rail cover 5 to the rear as
indicated by arrow.Step 4 (Disconnecting)
6Floor carpet
Pull back and fold floor carpet6 in
direction of the arrow.
iIf the vehicle battery is discharged and you
had the vehicle jump started, turn off the engine.
iTo release the floor carpet perforations (see
dotted line in above illustration), you will have to
apply somewhat greater force when pulling the
floor carpet back.

509 Practical hints
Battery
Step 8 (Disconnecting)
fPositive terminal with cover
gNegative terminal
Disconnect battery negative lead from
negative terminal g.
Make sure the negative lead does not
come into contact with the positive
lead.
Remove the cover from positive
terminal f.
Disconnect battery positive lead from
positive terminal f.Step 9 (Removing)
Take out battery.
Step 10 (Reinstalling)
Insert battery into the well under the
passenger seat.
Battery, shown removed for illustration
bBattery ventilation hose
hVent plug
Carry out step 11 (page 509) to
reconnect the battery .
Carry out steps 7 through 1 in reverse
order to completely reinstall the bat-
tery, (
page 508) to (page 505).
Step 11 (Reconnecting)
If the battery has been removed, carry
out step 10 (
page 509) before start-
ing the connecting procedure.
Open the driver’s door.
Make sure the SmartKey is removed
from the starter switch.
Vehicles with KEYLESS-GO*:
Make sure the vehicle’s on-board
electronics have status 0.
With the driver’s door opened, the
vehicle’s on-board electronics
have status 0, same as SmartKey
removed from the starter
switch (
page 41).!The battery, battery ventilation hoseb,
and vent plug h must always be securely
installed when the vehicle is in operation.

514 Practical hints
Towing the vehicle
If you want the gear position to remain in
neutral positionN, observe the following
instructions.Vehicles with SmartKey:
With the vehicle at a standstill and the
ignition switched on, shift the
automatic transmission to neutral
positionN.
If engaged, release the parking brake
(
page 56).
Switch off the ignition and leave the
SmartKey in the starter switch.
Vehicles with KEYLESS-GO*:
With the vehicle at a standstill, depress
the brake pedal and keep it pressed.
With the ignition switched on shift the
automatic transmission to park
positionP.
Release the brake pedal.
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. Adapt your driving accordingly.
!When towing the vehicle with all wheels on
the ground, the automatic transmission must be
in neutral positionN.
If you turn off the engine

using the SmartKey and

remove the SmartKey from the starter
switch
or

open a front door

or when using the KEYLESS-GO* start/stop
button and open a front door
the automatic transmission will shift to park
positionP automatically.
Warning!G
When leaving the SmartKey or SmartKey
with KEYLESS-GO* in the starter switch, do
not leave children unattended in the vehicle.
It is possible for children to switch on the
ignition which could result in unsupervised
use of vehicle equipment.
A child’s unsupervised access to a vehicle
could result in an accident and/or serious
personal injury.

515 Practical hints
Towing the vehicle
Remove the KEYLESS-GO* start/stop
button from the starter switch
(
page 41).
Insert the SmartKey with
KEYLESS-GO* into the starter switch.
Switch on the ignition.
Depress the brake pedal.
Shift the automatic transmission to
neutral positionN.
Release the brake pedal.
If engaged, release the parking brake
(
page 56).
Switch off the ignition and leave the
SmartKey with KEYLESS-GO* in the
starter switch.
Installing towing eye bolt
Depending on whether you are towing a
vehicle or you are being towed, the towing
eye bolt can be screwed into threaded
holes which are located behind covers on
the right-hand side of each bumper.
Example illustration R 550 4MATIC
1Towing eye cover
!Towing of the vehicle should only be done
using the properly installed towing eye bolt.
Never attach a tow cable, tow rope or tow rod to
the vehicle chassis, frame or suspension parts.
iTo signal turns while being towed with
hazard warning flasher in use, set the starter
switch to position2 and activate combination
switch for left or right turn signal in usual manner
– only the selected turn signal will operate.
Upon canceling the turn signal, the hazard warn-
ing flasher will operate again.

518 Practical hints
Fuses
The electrical fuses in your vehicle serve to
switch off malfunctioning power circuits.
If a fuse is blown, the components and
systems secured by that fuse will stop
operating.If a newly inserted fuse blows again, have
the cause determined and rectified by an
authorized Mercedes-Benz Light Truck
Center.
A fuse chart explains the fuse allocation
and fuse amperages. It is located in the
cargo compartment with the vehicle tool
kit (
page 469).
The electrical fuses are located in different
fuse boxes:

on the passenger side of the engine
compartment (
page 519)

in the cargo compartment
(
page 519)

in the passenger compartment
(
page 520)Before replacing fuses:
Apply the parking brake (page 65).
Make sure automatic transmission is
set to position P (
page 192).
The gear position indicator in the
multifunction display should be on
P.
Turn off all electrical consumers.
Turn off the engine (page 66).
Remove the SmartKey from the starter
switch.
Vehicles with KEYLESS-GO*:
Open the driver’s door (this puts
the starter switch to position0,
same as with the SmartKey re-
moved from starter switch). The
driver’s door can then be closed
again.
Warning!G
Only use fuses approved by Mercedes-Benz
with the specified amperage for the system
in question and do not attempt to repair or
bridge a blown fuse. Using other than
approved fuses or using repaired or bridged
fuses may cause an overload leading to a
fire, and/or cause damage to electrical
components and/or systems. Have the
cause determined and remedied by an
authorized Mercedes-Benz Light Truck
Center
iA blown fuse must be replaced by an appro-
priate spare fuse (recognizable by its color or the
fuse rating given on the fuse) of the amperage
recommended in the fuse chart.
Any Mercedes-Benz Light Truck Center will be
glad to advise you on this subject.

546 Index
Automatic climate control (3-zone)* 222
Air conditioning, Cooling 233
Air conditioning refrigerant 538
Air distribution 228
Air recirculation mode 231
Air vents, Front 222, 228
Air vents, Rear 236, 239, 240
Air volume 229
Control panel, Front 224
Control panel, Rear 236
Deactivating system 226
Defogging 230
Defrosting 229
Maximum cooling, MAXCOOL 231
Rear passenger compartment 236
Residual heat utilization (REST) 235
Automatic headlamp mode 144
Automatic lighting control, Interior
lighting 151
Automatic locking when driving 126
Automatic shift program 200Automatic transmission 190
Accelerator position 197
Automatic shift program 200
Emergency operation (limp-home
mode) 202
Gear ranges 199
Gear selector lever 53, 190
Gear shifting malfunctions 202
Hill start assist system 198
Kickdown 197
Program mode selector switch 200
Shifting procedure 193
Starting the engine 53
Steering wheel gearshift control 201
Transmission fluid level 360
Transmission positions 194
Automatic transmission fluid see ATF
AUX-socket 304B
Backrest
Seat 44
Seat, Lumbar support 132
Seat, Multicontour* 132
Backup lamps
Messages in the multifunction
display 455–460
Replacing bulbs 480
Bar 394
BAS 101
Lamps in instrument cluster 414
Messages in the multifunction
display 429
Batteries, SmartKey
Check lamp 110, 113
Checking battery condition 118
Batteries, SmartKey with KEYLESS-GO*
Checking battery condition 118
Battery, Vehicle 503
Charging 510
Disconnecting and connecting 505
Jump starting 511
Removing and installing 505
Bead 394
Beverage holder see Cup holder