2008 MERCEDES-BENZ GL550 page 164

511 Practical hints
Replacing bulbs
4Bulb socket of front fog lamp bulb
Turn bulb socket4 counterclockwise.
Pull bulb socket4 out of the housing.
Pull the front fog lamp bulb out of bulb
socket4.
Insert the new front fog lamp bulb into
bulb socket4.
Insert bulb socket4 into the housing.
Turn bulb socket4 clockwise until it
engages.
Plug in the electrical connector.
Insert front fog lamp2 back into
bumper.
Fasten retaining screws3.
Reinsert cover1 and press it in until it
engages.
Additional turn signal lamps bulbs
The additional turn signal lamps in the
exterior rear view mirrors have LEDs.
If a malfunction occurs or LEDs fail to func-
tion, the entire turn signal unit must be re-
placed. Have the turn signal unit replaced
by an authorized Mercedes-Benz Light
Truck Center.
Replacing bulbs for rear lamps
Before you start to replace a bulb for a rear
lamp, do the following first:
Turn the exterior lamp switch to
positionM (
page 143).
Tail lamp unit
Open the tailgate (page 122).
iTo access the bulb socket, you have to
remove the cover in the corresponding side trim
panel of the cargo compartment.
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513 Practical hints
Replacing bulbs
Replacing bulbs
1Bulb socket
2Clamp
Press and hold clamps2.
Pull bulb socket1 outwards.
Bulb socket
1Backup lamp
2Tail lamp, brake lamp, parking and
standing lamp
3Tail lamp, brake lamp, parking and
standing lamp, side marker lamp
4Turn signal lamp
5Rear fog lamp (driver’s side only)
Depending on which bulb needs to be
replaced, turn the respective
bulb1-5 counterclockwise.
Pull the bulb out of the housing.
Insert the new bulb into the bulb sock-
et.
Turn the bulb in the bulb socket clock-
wise carefully.
Insert the bulb socket into the rear
lamp.
Align bulb socket and press bulb sock-
et into rear lamp until it audibly engag-
es.
Make sure bulb socket is attached
properly.
Close the respective cover in the cargo
compartment.
Close the tailgate (page 123).
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514 Practical hints
Replacing bulbs
License plate lamp
1License plate lamp cover
2Screws
Loosen screws2.
Remove license plate lamp cover1.
Replace the tubular bulb.
Reinstall license plate lamp cover1.
Retighten screws2.
Adjusting headlamp aim
VVertical centerline
HHeadlamp mounting height, measured
from the centerCorrect headlamp adjustment is extremely
important. To check and readjust a head-
lamp, follow the steps described:
Park the vehicle on a level surface
25 feet (7.6 m) from a vertical test
screen or wall.
Switch the headlamps on
(
page 143).
If the beam does not show a beam pattern
as indicated in the figure left, then follow
the steps below:
Open hood (page 378).
iHigh beam adjustments simultaneously aim
the low beam.
Vehicle should have a normal tailgate load.
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515 Practical hints
Replacing bulbs
Example illustration headlamp, driver’s side
2Headlamp vertical adjustment screw
3Headlamp vertical adjustment screw
Always turn adjustment screws2
and3 simultaneously for vertical ad-
justment until the headlamp is adjust-
ed as shown1 (
page 514). Turn
clockwise for upward movement and
counterclockwise for downward move-
ment.
Graduations:
screw2:0.50° pitch
screw3:0.67° pitch
The left and right headlamps must be ad-
justed individually.
iIf it is not possible to obtain a proper head-
lamp adjustment, have the system checked at an
authorized Mercedes-Benz Light Truck Center.
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516 Practical hints
Replacing wiper blades
Front wiper blades
Removing
Remove the SmartKey from the starter
switch.
Vehicles with KEYLESS-GO*:
Make sure the vehicle’s on-board
electronics have status0
(
page 44).
Fold the wiper arms forward until they
engage.
1Wiper blade
2Cover
3Attachment
4Tab
5Removing
Press tabs4 together and tilt wiper
blade1 to detach tabs4 on both
recesses of attachment3.
Wiper blade1 is released on one end.
Maintaining its tilted position, slide
wiper blade1 out of attachment3 in
direction of arrow5.
Warning!G
For safety reasons, switch off wipers and
remove SmartKey from starter switch (vehi-
cles with KEYLESS-GO*: Make sure the
vehicle’s on-board electronics have
status
0) before replacing a wiper blade.
Otherwise the motor could suddenly turn on
and cause injury.
Warning!G
Wiper blades are components that are sub-
ject to wear and tear. Replace the wiper
blades twice a year, preferably in the spring
and fall. Otherwise the windows will not be
properly wiped. As a result, you may not be
able to observe surrounding traffic condi-
tions and could cause an accident.
!Never open the hood when the wiper arms
are folded forward.
Hold on to the wiper when folding the wiper arm
back. If released, the force of the impact from
the tensioning spring could crack the windshield.
Do not allow the wiper arms to contact the wind-
shield glass without a wiper blade inserted.
Make sure the wiper blades are properly
installed. Improperly installed wiper blades may
cause windshield damage.
For your convenience, we recommend that you
have this work carried out by an authorized
Mercedes-Benz Light Truck Center.
!Do not pull on the wiper blade inserts. They
could tear.
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518 Practical hints
Replacing wiper blades
Removing
Remove the SmartKey from the starter
switch.
Vehicles with KEYLESS-GO*:
Make sure the vehicle’s on-board
electronics have status0
(
page 44).
Fold wiper arm1 away from the rear
window until it engages.
1Wiper arm
2Wiper blade
Turn wiper blade2 to form a right
angle with wiper arm1 as shown.
Hold wiper arm1 and disengage wip-
er blade2 by carefully sliding it in
direction of arrow.
Remove wiper blade2.
Installing
1Wiper arm
2Wiper blade
Insert wiper blade2 into wiper
arm1.
Hold wiper arm1 and engage wiper
blade2 by pushing it in direction of
arrow until it locks into place.
Check whether the wiper blade is
securely fastened.
Fold the wiper arm to rest on the rear
window.
Make sure to hold on to the wiper when
folding the wiper arm back.
!Do not pull on the wiper blade insert. It
could tear.
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519 Practical hints
Flat tire
Flat tire
Preparing the vehicle
Make sure the vehicle level is set to
highway (
page 279).
Park the vehicle in a safe distance from
moving traffic on a hard, flat surface
when possible.
Turn on the hazard warning flasher
(
page 149).
Turn the steering wheel so that the
front wheels are in a straight-ahead
position.
Set the parking brake (page 59).
Set the automatic transmission to park
positionP (
page 191).
Turn off the engine (page 41).
Have any passenger exit the vehicle at
a safe distance from the roadway.
Vehicles with SmartKey: Remove the
SmartKey from the starter switch.
Vehicles with KEYLESS-GO*: Open the
driver’s door (this puts the starter
switch in position0, same as with the
SmartKey removed from the starter
switch). The driver’s door then can be
closed again.
Remove the KEYLESS-GO*
start/stop button from the starter
switch.
Warning!G
The dimensions of the Minispare wheel are
different from those of the road wheels. As
a result, the vehicle handling characteristics
change when driving with a Minispare wheel
mounted. Adapt your driving style accord-
ingly.
The Minispare wheel is for temporary use
only. When driving with a Minispare wheel
mounted, ensure proper tire pressure and
do not exceed a vehicle speed of
50 mph (80 km/h).
Drive to the nearest Mercedes-Benz Light
Truck Center as soon as possible to have the
Minispare wheel replaced with a regular
road wheel.
Never operate the vehicle with more than
one spare wheel mounted.
Do not switch off the ESP
® when a
Minispare wheel is mounted.
Warning!G
Your vehicle is equipped with air suspen-
sion. Do not open or close any doors or the
tailgate while mounting a spare wheel. The
vehicle could rise or lower to a previously se-
lected level. You or others could be injured
as a result.
iOpen door only when conditions are safe to
do so.
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520 Practical hints
Flat tire
Mounting the spare wheel
Preparing the vehicle
Prepare the vehicle as described
(
page 519).
Take the wheel wrench, the collapsible
wheel chock, and the vehicle jack out
of the cargo compartment
(
page 490).
Take the Minispare wheel out of the
cargo compartment (
page 495).Lifting the vehicle
!Depending on vehicle production date your
vehicle may be equipped with a scissors-type
jack (located under the cargo compartment
floor). If so equipped, only use this jack when
jacking up the vehicle as otherwise the vehicle’s
underbody can be damaged. See separate
instructions for scissors-type jack.
Warning!G
When jacking up the vehicle, only use the
jack which has been specifically approved
by Mercedes-Benz for your vehicle.
The jack is designed exclusively for jacking
up the vehicle at the jack take-up brackets
built into both sides of the vehicle. Make
sure the jack arm is fully seated in the jack
take-up bracket.
The jack is intended only for lifting the
vehicle briefly for wheel changes. It is not
suited for performing maintenance work
under the vehicle. To help avoid personal in-
jury, use the jack only to lift the vehicle dur-
ing a wheel change.
Never get beneath the vehicle while it is sup-
ported by the jack. Keep hands and feet
away from the area under the lifted vehicle.
Always lower the vehicle onto sufficient
capacity jackstands before working under
the vehicle.
Always firmly set parking brake and block
wheels with wheel chocks or other sizeable
objects before raising vehicle with jack. Do
not disengage parking brake while the vehi-
cle is raised.
Make sure that the ground on which the ve-
hicle is standing and where you place the
jack is solid, level and not slippery. If neces-
sary, use a large underlay. On slippery sur-
faces, such as tiled floors, you should use a
non-slip underlay, for example a rubber mat.
Do not use wooden blocks or similar objects
to support the jack. Otherwise the jack may
not be able to achieve its load-bearing ca-
pacity if it is not at its full height.
Never start the engine when the vehicle is
raised.
Also observe the notes on the jack.
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