2003 MERCEDES-BENZ G55AMG light

144 Controls in detailDifferential locksA few words about differentials and dif-ferential locks
When a vehicle negotiates a turn, wheels
on the outside of the curve must travel far-
ther and rotate faster than the inside
wheels. The differential, the operation of a
set of gears that allows the powered
wheels in a vehicle to turn at different
speeds, make this essential function possi-
ble.
The drawback is that the differential also
sends most of the engine's power to the
wheel with the least load or strain on it. For
example, if one of a vehicle's powered
wheels sits on a patch of snow and spins
because there is no traction, all of the en-
gine's power will go to that wheel because
the power will take the path of least resis-
tance. Meanwhile, the opposite wheel, sit-
ting on dry pavement where it could get
enough grip to start the vehicle moving,
sits idle because it receives no power.The Electronic Traction System (ETS) ad-
dresses this problem and provides for
good control and steering ability by auto-
matically slowing the slipping wheel and
thus increasing the power to the other
non-slipping drive wheels to get the vehicle
moving. The ESP and ETS in this vehicle
feature such intelligent limited-slip differ-
ential technology, ideally suited for
on-road and light off-road driving. Transfer
case position LOW (
page 141) also en-
hances off-road driving capabilities
(
page 203).
More extreme off-road conditions may call
for another solution, engaging a differen-
tial lock or preventing the differential from
operating altogether. As part of its stan-
dard equipment, this vehicle comes with
three differential locks: front, transfer case
(center) and rear. Each can be engaged
simply by pushing dashboard-mounted
buttons in sequential order (center, rear,
front) (
page 145). When the transfer
case (center) differential is locked, half of
the engine's power is automatically distrib-
uted to the front wheels and half to the rear wheels. When the rear differential is
locked, power going to the rear wheels is
equally distributed, so that both rear
wheels turn at the same speed and torque.
When the front differential is locked, all
four wheels now turn with equal power and
torque. Please be aware that engaging the
differential locks will significantly reduce
the steering ability of the vehicle.
For your safety and the safety of others
and to prevent damage to the vehicle, the
differential locks must not be engaged
when driving on paved roads. It is impor-
tant to understand that during
on-road/paved driving, differentials are
absolutely necessary for providing the es-
sential control and steering ability of the
vehicle. The differential locks, therefore,
must not be engaged when driving on
paved roads and should only be used to
the extent necessary to negotiate off-road
conditions which can not be handled by
the systems (automatic 4-ETS, the ESP,
manual switch position “LOW” of transfer
case) this vehicle comes equipped with.

145 Controls in detail
Differential locks
Switching differential locks on and off
The switch is located in the center console.
1Transfer case (center) differential lock
2Rear axle differential lock
3Front differential lock
4Engagement indicator lamps (yellow)
5Function indicator lamps (red)Switching differential locks on
Transfer case differential lock

Press switch1.
The yellow engagement indicator lamp
for the transfer case differential lock
lights up.
The
v
warning lamp lights up.
When the differential lock engagement
operation has been completed, the red
function indicator lamp lights up.The message
ABS NOT AVAILABLE –
DIFFERENTIAL LOCKED
appears in the
multifunction display.
The
v
and
-
warning lamps in
the instrument cluster come on.
Once the transfer case differential lock
is switched on, you can now, if needed,


switch on rear axle differential
lock2
or


switch on rear axle differential lock
and front differential lock 2 and 3.
iThe differential locks can only be
switched on in the sequence 1, 2, 3.
!To avoid damage to the transfer case
and differential locks:

Engage differential locks only at low
speed (walking speed, not more
than 5 mph)


Do not engage differential locks if
the driving wheels are spinning


Do not engage on paved roads.

146 Controls in detailDifferential locksRear axle differential lock
Press switch2.
The yellow engagement indicator lamp
lights up first, followed by the red func-
tion indicator lamp.
The rear axle differential lock is
switched on.
Front differential lock

Press switch 3.
The yellow engagement indicator lamp
lights up first, followed by the red func-
tion indicator lamp.
The front differential lock is switched
on. Switching differential locks off
There are two different methods to disen-
gage differential locks:


You can switch the differential locks off
in reverse order (3, 2, 1).


To switch off all differential locks at the
same time:
Press switch1.
The yellow engagement indicator
lamps go out first. The red function
indicator lamps go out when the
switching process has been carried
out in the differential.To activate the ESP, BAS and ABS systems,
drive again for three seconds using a con-
stant driving style.
All messages in the multifunction display
disappear. The
v
and
-
warning
lamps in the instrument cluster go out.
iIf the function lamps do not go out
when the differential locks are disen-
gaged, bring vehicle to a stop and then
continue driving. Changing the vehicle
load can help to disengage locks. Warning!
G
Always remember to disengage the differen-
tial locks when returning to drive on paved
roads, see “A few words about differentials
and differential locks” (
page 144).

147 Controls in detail
Good visibility
Good visibility
Information on the windshield wipers
(page 47) and for setting the rear view
mirrors (
page 38) is found in the “Get-
ting started” section.
Rear view mirror
Automatic antiglare rear view mirror
The reflection brightness of the inside rear
view mirror will respond automatically to
glare when

the ignition is switched on, and


incoming light from headlamps falls on
the sensor in the inside rear view mir-
ror
The rear view mirror will not react if


reverse gear is engaged


the interior lighting is turned on
Warning!
G
The automatic antiglare function does not
react if incoming light is not aimed directly
at sensors in the inside rear view mirror.
The inside rear view mirror does not react,
for example, if the cargo area is fully loaded.
Glare can endanger you and others.Warning!
G
Exercise care when using the passenger
side exterior rear view mirror. The mirror
surface is convex (outwardly curved surface
for a wider field of view). Objects in mirror
are closer than they appear. Check your in-
side rear view mirror or glance over your
shoulder before changing lanes.
Warning!
G
In the case of an accident, liquid electrolyte
may escape from the mirror housing if the
mirror glass breaks.
Electrolyte has an irritating effect. Do not al-
low the liquid to come into contact with
eyes, skin, clothing, or the respiratory sys-
tem. In case it does, immediately flush af-
fected area with water, and seek medical
help if necessary.

149 Controls in detail
Good visibility
Sun visors
The sun visors protect you from sun glare
while driving.
1Sun visor
2Mounting

Swing sun visors 1 down to protect
against sun glare.

If sunlight enters through a side win-
dow, disengage visor 1 from inner
mounting 2 and pivot it to the side.3Mirror cover
4Mirror lamp

Make sure that the ignition is switched
on and that the sun visor is engaged in
mounting 2.

Open mirror cover3.
Mirror lamp4 switches on.
Warning!
G
Do not use the vanity mirror while driving.
Keep the mirrors in the sun visors closed
while vehicle is in motion. Reflected glare
can endanger you and others.

155 Controls in detail
Climate control
Rear window defroster
Turn the SmartKey in starter switch to
position2.
Activating
Press button
F
in the control panel
of the climate control.
The indicator lamp in the button lights
up.
Deactivating

Press button
F
in the control panel
of the climate control.
The indicator lamp in the button goes
out.
!Heavy accumulation of snow and ice
should be removed before activating
the defroster.
The defroster is automatically turned
off after approximately 6-17 minutes of
operation depending on the outside
temperature and vehicle speed.
If several power consumers are turned
on simultaneously, or the battery is
only partially charged, it is possible that
the defroster will automatically turn it-
self off.
When this happens, the indicator lamp
inside the switch starts blinking.
As soon as the battery has sufficient
voltage, the defroster turns itself back
on.
iThe rear window defroster uses a large
amount of power. To keep the battery
drain to a minimum, turn off the de-
froster as soon as the rear window is
clear.

156 Controls in detailClimate controlResidual engine heat utilization
With the engine switched off, it is possible
to continue to heat or ventilate the interior
for a short while, depending on the temper-
ature setting of the climate control. Air vol-
ume and distribution are controlled
automatically.
Activating
Turn the SmartKey in starter switch to
position1 or0 or remove it altogether.

Press button
°
.
The indicator lamp in the button lights
up.
Set the left and right temperature to
your personal requirements.Deactivating

Press button
°
again to switch off.
The indicator lamp in the button goes
out.
The residual heat is automatically turned
off:


when the SmartKey in starter switch is
turned to position2


after about 30 minutes


if the battery voltage dropsDeactivating the climate control
system
Deactivating
Set the air volume control switch to
position0.
Reactivating

Set the air volume control switch to any
speed.

157 Controls in detail
Climate control
Air conditioning
The air conditioning is operational while
the engine is running and cools the interior
air to the temperature set by the operator.
Deactivating
It is possible to deactivate the air condi-
tioning (cooling) function of the climate
control system. The air in the vehicle will
then no longer be cooled or dehumidified.
Press button
°
(page 151).
The indicator lamp on the button
°

lights up.Activating
Moist air can fog up the windows. You can
dehumidify the air with the air conditioner.

Press button
°
again (
page 151).
The indicator lamp on the button
°

goes out.
The air conditioner uses the refrigerant
R134a. This refrigerant is free of CFCs
which are harmful to the ozone layer.Rear passenger compartment adjust-
able air vents
1Air volume control for center air vents
2Left center air vent, adjustable
3Right center air vent, adjustable
iCondensation may drip out from under-
neath the vehicle. This is normal and
not an indication of a malfunction.
!If the
°
button on the climate con-
trol panel starts to blink, this indicates
that the air conditioner is losing refrig-
erant. The compressor has turned itself
off. The air conditioner cannot be
turned on again.


Have the air conditioner checked at
the nearest authorized
Mercedes-Benz Center.