2007 MERCEDES-BENZ GL450 Owner's Manual

536 Practical hints
Battery
Step 8 (Removing)
cBattery
Tilt the batteryc with the negative
terminal side upwards.
Take out the battery maintaining its
tilted position in the direction of the
arrow.Step 9 (Reinstalling)
Carry out step 8 in reverse order
(
page 536).
Battery, shown removed for illustration
9Battery ventilation hose
dVent plug
Carry out step 10 to reconnect the
battery (
page 536).
Follow steps 5 to 1 in reverse order to
completely reinstall the battery
(
page 535) to (page 532).
Step 10 (Reconnecting)
If the battery has been removed, first
carry out step 8 in reverse order
(
page 536).
Open the driver’s door.
Make sure all electrical consumers are
turned off.
Make sure the SmartKey is removed
from the starter switch.
Vehicles with KEYLESS-GO*:
Make sure the vehicle’s on-board
electronics have status0 (Open the
driver’s door. With the driver’s door
open, the vehicle’s on-board elec-
tronics have status0, same as with
the SmartKey removed from the
starter switch (
page 41)).
!The battery, the battery ventilation hose9
and the lateral plugd (
page 536) must
always be securely installed when the vehicle is
in operation.

537 Practical hints
Battery
Connect the positive lead to the posi-
tive terminal and fasten it’s cover
(
page 535).
Connect the negative lead to the nega-
tive terminal (
page 535).
Charging the battery
If the battery is discharged, the battery can
be charged using the jump-start contacts
located in the engine compartment
(
page 539).
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 reconnection):

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 251).

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

Synchronize the power folding exterior rear
view mirrors* (
page 212).
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.

538 Practical hints
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 located
in the engine compartment
(
page 539).

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 higher voltage 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 catalyt-
ic 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.

539 Practical hints
Jump starting
The jump-start contacts are located in the
engine compartment.
1Negative (-) terminal
2Positive (+) terminal
3Positive terminal cover
Make sure the two vehicles do not
touch.
Turn off all electrical consumers.
Apply parking brake (page 68).
Set automatic transmission to
positionP (
page 194).
Open the hood (page 379).
Remove cover from negative
terminal1.
Flip up cover3 of positive terminal2
in direction of arrow.
1Negative terminal of discharged
battery
2Positive terminal of discharged battery
4Positive terminal of charged battery
5Negative terminal of charged battery
Connect positive terminal2 and4
with the jumper cable. Clamp cable to
charged battery4 first.
Start engine of the vehicle with the
charged battery and run at idle speed.
Connect negative terminals1 and5
of the batteries with the second jumper
cable. Clamp the cable to negative
terminal5 of the charged battery
first.
Start the engine of the disabled vehi-
cle.
You can now turn on the electrical consum-
ers. Do not switch on the headlamps under
any circumstances.
Remove the jumper cables first from
negative terminals1 and5 and then
from positive terminals2 and4.
You can now switch on the headlamps.
Have the battery checked at the near-
est authorized Mercedes-Benz Light
Truck Center.
Warning!G
Keep flames or sparks away from battery.
Do not smoke.
Observe all safety instructions and precau-
tions when handling automotive batteries
(
page 530).
!Never invert the terminal connections!

540 Practical hints
Towing the vehicle
Mercedes-Benz recommends that the
vehicle be transported with all wheels off
the ground using flatbed or appropriate
wheel lift/dolly equipment. This method is
preferable to other types of towing.If circumstances do not permit the recom-
mended towing methods, the vehicle may
be towed with all wheels on the ground
only so far as necessary to have the vehicle
moved to a safe location where the recom-
mended towing methods can be employed.
When towing the vehicle with all wheels on
the ground, the vehicle may be towed only
for distances up to 30 miles (50 km) and at
a speed not to exceed 30 mph (50 km/h).
!Do not tow-start the vehicle.
!Use flatbed or wheel lift/dolly equipment,
with the SmartKey in starter switch turned to
position0.
Do not tow with sling-type equipment. Towing
with sling-type equipment over bumpy roads will
damage radiator and supports.
To prevent damage during transport, do not tie
down vehicle by its chassis or suspension parts.
Use the towing eyes.
Switch off the ESP
® (page 107) and the
automatic central locking (
page 130).
!Do not tow with one axle raised. Doing so
could damage the transfer case, which is not
covered by the Mercedes-Benz Limited
Warranty.
All wheels must be on or off the ground. Observe
instructions for towing the vehicle with all
wheels on the ground.
Warning!G
If circumstances require towing the vehicle
with all wheels on the ground, always tow
with a tow bar if

the engine will not run

there is a malfunction in the brake
system

there is a malfunction in the power
supply or in the vehicle’s electrical
system
as that will be necessary to adequately
control the towed vehicle.
Prior to towing the vehicle with all wheels on
the ground, make sure the starter switch is
in position2 (
page 42).

541 Practical hints
Towing the vehicle
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
positionN (
page 193).

The starter switch must be in position2
(
page 41).
Keep in mind that it is important that the
starter switch is in position2. As soon as the
SmartKey is removed from the starter
switch or the engine is turned off with
KEYLESS-GO* and you open the driver’s
door or the front passenger door, the auto-
matic transmission will shift to park
positionP, see “Starter switch positions”
(
page 41).

The battery must be connected and charged.
Otherwise, the starter switch cannot be set
to position2 and the automatic transmission
will remain locked in positionP.
!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.
iWhen towing the vehicle with all wheels on
the ground, note the following:
With the automatic central locking activated and
the starter switch in position2 (
page 41), the
vehicle doors lock if a wheel is turning at a speed
of approximately 9 mph (15 km/h) or above.
To prevent the vehicle doors from locking,
deactivate the automatic central locking
(
page 130).
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
warning flasher will operate again.

542 Practical hints
Towing the vehicle
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.
1Cover1CoverRemoving cover
Press mark on cover1 as indicated by
the arrow.
Lift off cover1 to reveal the threaded
hole for towing eye bolt.
Installing towing eye bolt
Take the towing eye bolt and wheel
wrench from the vehicle tool kit
(
page 495).
Screw towing eye bolt in clockwise to
its stop and tighten with wheel wrench.
Removing towing eye bolt
Loosen towing eye bolt counterclock-
wise with wheel wrench.
Unscrew towing eye bolt.
Store the towing eye bolt and wheel
wrench back into the vehicle tool kit
(
page 495).
Warning!G
In order to avoid possible serious burns or
injury, use extreme caution when removing
the rear cover, because the rear exhaust
pipe is extremely hot.
iThe cover1 is secured to the bumper by a
plastic cord.

543 Practical hints
Towing the vehicle
Installing cover
Engage cover1 at top and press at
bottom.
Stranded vehicle
Freeing a stranded vehicle, on which the
wheels are dug into sand or mud, should
be done with the greatest of care, especial-
ly if the vehicle is heavily loaded.
Avoid pulling the vehicle abruptly or diago-
nally, since it could result in damage to the
chassis alignment.
Never try to free a vehicle that is still cou-
pled to a trailer.
If possible, a vehicle equipped with trailer
hitch receiver should be pulled backward
in its own previously made tracks.