ABS MERCEDES-BENZ G500 2003 W463 User Guide

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).

162 Controls in detailDriving systems
Driving systemsThe driving systems of your vehicle are de-
scribed on the following pages:

Cruise control, with which the vehicle
can maintain a preset speed.


Rear Park Assist*, with which you can
assist your parking maneuvers.
The BAS, ABS, ESP, 4-ETS and EBB driving
systems are described in the “Safety and
Security” section (
page 71).
Cruise control
Cruise control automatically maintains the
speed you set for your vehicle.
Use of cruise control is recommended for
driving at a constant speed for extended
periods of time. You can set any speed
over 20 mph (30 km/h).
The cruise control function is operated by
means of the cruise control lever.
The cruise control lever is the uppermost
lever found on the left-hand side of the
steering column (
page 22).
iThe cruise control should not be acti-
vated during-off road driving.
Warning!
G
Cruise control is a convenience system de-
signed to assist the driver during vehicle op-
eration. The driver is and must always
remain responsible for the vehicle speed
and for safe brake operation.
Only use cruise control if the road, traffic
and weather conditions make it advisable to
travel at a steady speed.

The use of cruise control can be danger-
ous on winding roads or in heavy traffic
because conditions do not allow safe
driving at a steady speed.


The use of cruise control can be danger-
ous on slippery roads. Rapid changes in
tire traction can result in wheel spin and
loss of control.


Deactivate cruise control when driving
in fog.
The “Resume” function should only be oper-
ated if the driver is fully aware of the previ-
ously set speed and wishes to resume this
particular preset speed.

202 OperationDriving instructionsWinter driving instructions
The most important rule for slippery or icy
roads is to drive sensibly and to avoid
abrupt acceleration, braking and steering
maneuvers. Do not use the cruise control
system under such conditions.
When the vehicle is in danger of skidding,
move selector lever to positionN. Try to
keep the vehicle under control by correc-
tive steering action.Road salts and chemicals can adversely af-
fect braking efficiency. Increased pedal
force may become necessary to produce
the normal brake effect.
We therefore recommend depressing the
brake pedal periodically when traveling at
length on salt-strewn roads.
This can bring road salt impaired braking
efficiency back to normal. Be very careful
that you carry out these braking maneu-
vers without endangering any other road
users.
If the vehicle is parked after being driven
on salt-treated roads, the braking efficien-
cy should be tested as soon as possible af-
ter driving is resumed while observing the
safety rules in the previous paragraph.
For more information on winter driving
(
page 228).
iInformation on driving with snow
chains (
page 229).
Warning!
G
On slippery road surfaces, never downshift
in order to obtain braking action. This could
result in drive wheel slip and reduced vehi-
cle control. Your vehicle’s ABS will not pre-
vent this type of control loss.
Do not engage the transfer case in position
LOW when driving on ice or packed snow. At
speeds below 18 mph (30 km / h) vehicle
steering is adversely affected by the LOW
RANGE – ABS (
page 72).
Warning!
G
If the vehicle becomes stuck in snow, make
sure that snow is kept clear of the exhaust
pipe and from around the vehicle with the
engine running. Otherwise, deadly carbon
monoxide (CO) gases may enter vehicle in-
terior resulting in unconsciousness and
death.
To assure sufficient fresh air ventilation,
open a window slightly on the side of the ve-
hicle not facing the wind.Warning!
G
The outside temperature indicator is not de-
s i g n e d t o s e r v e a s a n i c e - w a r n i n g d e v i c e a n d
is therefore unsuitable for that purpose. In-
dicated temperatures just above the freez-
ing point do not guarantee that the road
surface is free of ice.

204 OperationDriving instructionsRead this chapter carefully before you be-
gin off-road travel.
Familiarize yourself with the vehicle char-
acteristics and gear changing before you
attempt any difficult terrain off-road driv-
ing. We recommend that you start out with
easy off-road travel.Special driving features for off-road
driving
The following driving features are available
for specific kind of operation:


ABS (
page 71)


ESP (
page 75)


4-ETS (
page 74)


Differential lock (
page 145)


Transfer case (
page 141)
Off-road driving rules

Engage the transfer case in position
LOW before driving under off-road con-
ditions (
page 141).

If necessary activate differential locks
(page 145).
The ABS, BAS and ESP are switched off
automatically when the differential
locks are activated.

Fasten items being carried as securely
as possible (
page 173).
Never let the vehicle roll backwards in idle.
You may lose control of the vehicle if you
use only the service brake.
Sand, dirt, mud and other material having
friction property can cause exceptional wear
and tear as well as brake failure.
Have the brakes checked for dirt build-up
and cleaned. There is otherwise a risk that
full braking power may not be available in an
emergency.
iWhenever driving in off-road mode, we
recommend:

Keeping doors, tailgate, windows
and sliding/pop-up roof closed.


Switching cruise control off.
!Observe the following during off-road
driving:

Adjust vehicle speed to condition of
terrain. The more uneven, rutty and
steeper the terrain, the lower the
speed should be. Drive through wa-
ter slowly at an even speed, avoid-
ing a bow wave.


Be especially careful when driving
in unknown territory. It may be nec-
essary to get out of the vehicle and
scout the path you intend to take.


Watch out for obstacles, such as
rocks, holes, tree stumps and ruts.

207 Operation
Driving instructions
Driving downhill

Select gear range1 on the automatic
transmission (
page 137).


Drive downhill observing the same
rules as driving uphill (
page 206).Driving through water
119 in (48 cm)


Before driving through water, deter-
mine its depth.
It should not be deeper than approxi-
mately 19 in (48 cm).


Comply with the warnings
(page 203) and rules for off-road
driving (
page 204).


Switch off the exterior lamps as well as
the climate control.


Select gear range2 or1 on the auto-
matic transmission (
page 137).


Enter the water only at a shallow spot,
driving at walking speed.


Do not stop vehicle immersed in water,
and do not shut off the engine.
There is a very high level of driving re-
sistance in water. The surface is slip-
pery and may not be firm, making
pulling away in water difficult and dan-
gerous.


Clean mud off the tire tread after driv-
ing through water.


To dry the brakes, apply pressure to the
brake pedal several times after leaving
the water.
!Only apply the service brake if the vehi-
cle travels straight downhill, i.e. in the
line of gravity.iThe special LOW RANGE – ABS setting
allows for precise and brief (cyclical)
blocking of the front wheels, permitting
them to dig into loose ground.
Remember that, when stopped, the
front wheels slide across a surface and
thus lose their ability to steer the vehi-
cle.
!Never accelerate before driving into
the water. The bow wave could force
water into the engine and auxiliary
equipment, thus damaging them.

228 OperationWinter driving
Winter drivingBefore the onset of winter, have your vehi-
cle winterized at an authorized
Mercedes-Benz Light Truck Center. This
service includes:

Check of anticorrosion and antifreeze
concentration.


Addition of cleaning concentrate to the
water of the windshield and headlamp
cleaning system. Add MB Concentrate
“S” to a premixed windshield washer
solvent/antifreeze which is formulated
for below freezing temperatures
(page 321).


Battery test. Battery capacity drops
with decreasing ambient temperature.
A well charged battery helps to ensure
that the engine can be started even at
low ambient temperatures.


Tire change. We recommend M+S rat-
ed radial-ply tires on all four wheels for
the winter season.
Winter tires
Always use winter tires at temperatures
below 39°F (4°C) and whenever wintry
road conditions prevail. Use of winter tires
is the only way to achieve the maximum ef-
fectiveness of the ABS, ESP, EBB and
4-ETS in winter operation.
For safe handling, ensure that all winter
tires mounted are of the same make and
have the same tread design.
Always observe the speed rating of the
winter tires installed on your vehicle. If the
maximum speed for which your tires are
rated is below the speed rating of your ve-
hicle, you must place a notice to this effect
where it will be seen by the driver. Such no-tices are available from your tire dealer or
from any authorized Mercedes-Benz Light
Truck Center.
Block heater (Canada only)
The engine is equipped with a block heat-
er.
The electrical cable may be installed at
your authorized Mercedes-Benz Center.
Warning!
G
Winter tires with a tread depth under 0.16 in
(4 mm) must be replaced. They are no long-
er suitable for winter operation.
Warning!
G
If you use your spare tire when winter tires
are fitted on the other wheels, be aware that
the difference in tire characteristics may
very well impair turning stability and that
overall driving stability may be reduced.
Adapt your driving style accordingly.
Have the spare tire replaced with a winter
tire at the nearest authorized
Mercedes-Benz Light Truck Center.

238 Practical hintsWhat to do if …
What to do if …Lamps in instrument clusterGeneral information:
If a bulb in the instrument cluster fails to
light up during the bulb self-check when turning the SmartKey in starter switch to
position2, have it checked and replaced if
necessary.Problem
Possible cause
Suggested solution
v
The yellow ESP warning lamp
lights up and remains on while
driving.
You engaged the differential locks. The ABS,
ESP, BAS, EBB and 4-ETS are switched off.

The driving systems will switch on
again after the differential locks have
been disengaged.

Also note the messages in the multi-
function display (
page 246).
The ESP is deactivated. Risk of accident!
Adapt your speed and driving to the prevail-
ing road conditions.

Turn the ESP back on (
page 78).
If the ESP cannot be turned back on, have
the system checked at an authorized
Mercedes-Benz Light Truck Center as
soon as possible.
The ESP is deactivated because of interrupt-
ed power supply. The ABS may still be opera-
tional. The ESP has to be synchronized.

Note the messages in the multifunc-
tion display (
page 246).
The ESP, ABS, BAS, EBB or 4-ETS has detect-
ed a malfunction. All driving systems are
switched off. Risk of accident! Adapt your
speed and driving to the prevailing road con-
ditions.

Note the messages in the multifunc-
tion display (
page 246).

240 Practical hintsWhat to do if …Problem
Possible cause
Suggested solution
-
The yellow ABS malfunction indi-
cator lamp comes on while driv-
ing.
You engaged the differential locks. The ABS,
ESP, BAS, EBB and 4-ETS are switched off.

The driving systems will switch on
again after the differential locks have
been disengaged.
The ABS has detected a malfunction and has
switched off. The ESP, BAS, EBB and 4-ETS
are also switched off (see messages in dis-
play).
If the ABS control unit is malfunctioning, oth-
er systems such as the navigation system or
Rear Park Assist* may also malfunction.
The brake system is still functioning normally
but without the ABS available.

Continue driving with added caution.
Wheels will lock during hard braking
reducing steering capability.

Have the system checked at an autho-
rized Mercedes-Benz Light Truck Cen-
ter as soon as possible.
Failure to follow these instructions in-
creases the risk of an accident.
The ABS has switched off because charging
voltage has fallen below 10 volts. The battery
may not be charged.

Turn off unnecessary electric con-
sumers.
When the battery voltage is above this
value again, the ABS is operational
again.

Note the messages in the multifunc-
tion display (
page 246).