2008 MERCEDES-BENZ R350 Owner's Manual

504 Practical hints
Battery
!The battery is a valve-regulated lead acid
(VRLA) battery, also referred to as “fleece”
battery. Such batteries do not require topping-up
of the electrolyte level. VRLA batteries therefore
do not have cell caps and the battery cover is
non-removable. Do not attempt to open the
battery as otherwise the battery will be dam-
aged.
Even though VRLA batteries do not require
topping-up of the electrolyte level and cannot be
opened to check the electrolyte level, the
battery condition must be checked periodically
by performing a battery conductance test. Refer
to Maintenance Booklet for battery condition
testing intervals.
As with any other battery, the battery may
discharge if the vehicle is not operated for an
extended period of time. You can connect a
battery maintenance charge unit tested and
approved for use on your vehicle model or dis-
connected the battery to prevent battery dis-
charge. Contact an authorized Mercedes-Benz
Light Truck Center for more information.!The factory-equipped VRLA battery is
leak-proofed. Only use a battery as replacement
that has the same security features and is of
identical size, voltage, and capacity as the
factory-equipped battery.
The battery, the battery ventilation and the later-
al plug must always be securely installed when
the vehicle is in operation.
Warning!G
Jump starting must only be done using the
jump-start contacts located in the engine
compartment (
page 511).
Warning!G
Failure to follow these instructions can re-
sult in severe injury or death.
Observe all safety instructions and precau-
tions when handling automotive batteries
(
page 503).
Never lean over batteries while connecting,
you might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking etc.

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.


506 Practical hints
Battery
Switch off all electrical consumers.
Read and observe safety instructions
and precautions (
page 503).
Open the front passenger door.
Move the front passenger seat to the
most rearward position (
page 45).Step 2 (Disconnecting)
1Seat rail cover, front right
2Seat rail cover, front left
Pull off right seat rail cover 1 in direc-
tion of arrow.
Pull left seat rail cover 2 in direction
of arrow as far as it will go.
Left seat rail cover 2 cannot be re-
moved.3Battery cover mounting nuts
Using a 6 mm T-handle hex key (not
supplied with vehicle) with a minimum
shaft length of 12 in (30 cm), unfasten
and remove battery cover mounting
nuts 3 located at the floor carpet per-
foration.
Move the front passenger seat to the
most forward position (
page 45).
iIf the vehicle battery is discharged and you
had the vehicle jump started:

Leave the engine running.

Complete step 1, starting with switching off
all electrical consumers.

Continue with step 2.

When the font passenger seat is in the most
forward position, turn off the engine.
iOpen doors only when conditions are safe to
do so.


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.

508 Practical hints
Battery
Step 5 (Disconnecting)
7Battery cover mounting nuts
Unfasten and remove battery cover
mounting nuts 7.Step 6 (Disconnecting)
8Battery cover with integrated air
channel
9Pulling battery cover out
aLifting battery cover
Lift battery cover 8 slightly in direc-
tion of arrow a.
Pull battery cover 8 in direction of
arrow 9.
Remove battery cover 8.Step 7 (Disconnecting)
bBattery ventilation hose
cBattery
dBattery attachment
eAttachment nuts
Pull battery ventilation hose b out of
battery c.
Unfasten and remove attachment
nutse.
Remove battery attachment d.
Push battery c to the left.

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.

510 Practical hints
Battery
Connect the positive lead to the posi-
tive terminal and fasten it’s cover
(
page 509).
Connect the negative lead to the nega-
tive terminal (
page 509).
Charging the battery
If the battery is discharged, the battery can
be charged using the jump-start contacts
located in the engine compartment
(
page 512).
Charge the battery in accordance with
the instructions of the battery charger
manufacturer.
Batteries contain materials that can harm
the environment if disposed of improperly.
Large 12-volt storage batteries contain
lead. Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.
!Never invert the terminal connections!
iThe following procedures must be carried
out following any interruption of battery power
(e.g. due to disconnection):

Set the clock (page 176).
Vehicles with COMAND system with naviga-
tion module*: Time and date are set auto-
matically.

Synchronize the door windows
(
page 244).

Synchronize the power tilt/sliding sunroof*
(
page 250).

Synchronize the power tilt/sliding panel*
(
page 255).

Synchronize the power folding exterior rear
view mirrors* (
page 204).
Warning!G
Never charge a battery while still installed in
the vehicle unless the accessory battery
charge unit approved by Mercedes-Benz is
being used. Gases may escape during charg-
ing and cause explosions that may result in
paint damage, corrosion or personal injury.
An accessory battery charge unit specially
adapted for Mercedes-Benz vehicles and
tested and approved by Mercedes-Benz is
available, permitting the charging of the
battery in its installed position. Contact an
authorized Mercedes-Benz Light Truck
Center for information and availability.
Charge battery in accordance with the
separate instructions for the accessory
battery charger.


511 Practical hints
Jump starting
Jump starting
If the battery is discharged, the engine can
be started with jumper cables and the bat-
tery of another vehicle. Observe the follow-
ing:

Jump starting should only be performed
using the jump-start contacts in the en-
gine compartment (
page 512).

Jump starting should only be performed
when the engine and catalytic
converter
1 are cold.

Do not start the engine if the battery is
frozen. Let the battery thaw out first.

Only jump start from batteries with the
same voltage rating (12 V). Jump start-
ing with a more powerful battery could
damage the vehicle’s electrical system,
which will not be covered by the
Mercedes-Benz Limited Warranty.

Only use jumper cables with sufficient
cross-section and insulated terminal
clamps.

Always make sure the jumper cables
are not on or near pulleys, fans or other
parts that move when the engine is
started or running.
Warning!G
Failure to follow these directions will cause
damage to the electronic components, and
can lead to a battery explosion and severe
injury or death.
Never lean over batteries while connecting
or jump starting, you might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water, and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and very explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking, etc.
Attempting to jump start a frozen battery
can result in it exploding, causing personal
injury.
Read all instructions before proceeding.
1Vehicles with gasoline engine only.
!Do not tow-start the vehicle.
!Avoid repeated and lengthy starting
attempts.
Do not attempt to start the engine using a
battery quick charge unit.
If the engine does not run after several unsuc-
cessful starting attempts, have it checked at the
nearest authorized Mercedes-Benz Light Truck
Center.
Excessive unburned fuel generated by repeated
failed starting attempts may damage the cata-
lytic converter
1.
Make sure the jumper cables do not have loose
or missing insulation.
Make sure the cable clamps do not touch any
other metal part while the other end is still at-
tached to a battery.