Mode E MERCEDES-BENZ ML320 1997 Complete Service Manual

183 Driving instructions
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Familiarize yourself with the vehicle characteristics and
gear changing before you attempt any difficult terrain
off-road driving. We recommend that you start out with
easy off-road travel.
Please read this chapter carefully before you begin
off-road travel.
Special driving features are available for specific kinds
of operation:
•LOW RANGE mode, see page 209
•LOW RANGE - ABS, see page 202
•LOW RANGE - 4-ETS+, see page 204
•LOW RANGE - ESP, see page 208
Engage the LOW RANGE mode before driving under
off-road conditions. For switching LOW RANGE mode on
and off see page 209.
Fasten items being carried as securely as possible, see
page 136.
We recommend to keep doors, liftgate, windows, and
roof closed whenever driving in off-road mode.Important!
Adjust vehicle speed to condition of terrain. The more
uneven, rutty and steeper the terrain, the lower the
speed should be.
Watch out for obstacles, such as rocks, holes,
tree-stumps, ruts.
Be especially careful when driving in unknown
territory. Eventually get out of the vehicle and scout the
path you intend to take.
Continuous and speedy driving in sandy soil overcomes
the vehicle rolling resistance, and helps to prevent the
vehicle from sinking into the ground.
Do not initiate jumps with the vehicle. It interrupts the
forward momentum of the vehicle.
Sand, dirt, mud and other material having friction
property, can cause exceptional wear and tear as well as
failure of the brakes.
In this case the brakes may be less effective or even fail
when you most need them. Always clean and check the
brakes following each off-road trip.

184 Driving instructions
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Checklist before off-road driving
•Tires: Check the tread depth and maintain specified
tire pressure (see tire pressure label inside the fuel
filler flap). Check tires for possible damage and
remove foreign objects. The valve caps must be
mounted.
•Rims: Dented or bent rims can cause tire pressure
loss and damage the tire beads. For this reason
change rims before driving off-road.
• Vehicle tool kit: Check if the vehicle jack is
functional. In all cases take the vehicle tool kit, a
strong tow rope, a shovel and a small plank (to put
under the vehicle jack on sandy soil) with you.Driving in steep terrain
Slope angle:
126° (ML 320 and ML 430)
23° (ML 55 AMG)
226° (ML 320 and ML 430)
21° (ML 55 AMG)
Switch to LOW RANGE mode before starting to drive up
or down steep inclines, see page 209.
Maximum vehicle climbing ability is a 60% grade.
1
2

185 Driving instructions
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cluster displayPractical hints Car care Index Driving on embankments, slopes and other steep
inclines should only be done straight up or downhill, i.e.
in the line of gravity.
Do not drive along the side of a slope (danger of vehicle
rollover). If in doing so, the vehicle begins to show a
tendency to roll, immediately steer into a line of gravity
(straight up or downhill).
To help avoid the vehicle rolling over, never turn it
around on steep inclines. If the vehicle cannot complete
the attempted climb, back it down in reverse gear.
Utilize the engine’s braking power when descending a
slope, observe the engine speed (do not overrev the
engine). Apply the service brake as needed.
Check the brakes after a lengthy downgrade drive.
Notes:
Avoid excessive engine speeds – drive with moderate
engine speeds (max. 3000 RPM).
Select gear range “2” or “1” on the automatic
transmission, see page 165.Traction in steep terrain:
Be easy on the accelerator and watch for continuous
wheel traction when driving in steep terrain.
The 4-ETS+ helps greatly when starting out on a steep
incline. The front wheels have then the tendency to slip
due to the weight reduction over the front axle. The ETS
recognizes the situation and limits the torque for the
front wheels by braking them. Simultaneously the
torque for the rear wheels is increased.
See page 203 for four wheel electronic traction system
(4-ETS+).
Driving across a hilltop:
To prevent the vehicle from speeding up too much after
climbing a hill, decelerate just ahead of a hilltop (do not
select gear range “N”). Use the momentum of the
vehicle to drive across the hilltop. Driving in this
manner prevents the vehicle from jumping across the
hilltop and thus loosing its forward momentum.

187 Driving instructions
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120 in (50 cm)
Before driving through water, determine its depth. It
should not be deeper than approximately
20 inches (50 cm).Switch to LOW RANGE mode before driving through
water.
Switch off the exterior lamps as well as the climate
control.
Enter the water only at a shallow spot. Never take a
running start. Drive slowly, avoiding a bow wave.
Do not stop vehicle immersed in water, and do not shut
off the engine.
To dry the brakes, apply pressure to the brake pedal
several times after leaving the water.

189 Driving instructions
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Off-road driving increases strain on the vehicle.
We recommend that you inspect the vehicle for possible
damage after each off-road trip. Recognizing any
damage and a subsequent timely repair reduces the
chance of a possible breakdown or accident later on.
Proceed as follows:
•Switch off the LOW RANGE mode, see page 209.
•Remove excessive dirt from tires, wheels, wheel
housings, and underbody. For instance, after driving
in mud, clean the radiator, chassis, engine, brakes,
and wheels from extreme dirt, using a strong jet of
water.
•Inspect frame, oil pan, brake hoses, etc., as well as
vehicle underbody for possible damage.
•Check tires for possible damage, clean all exterior
lamps, and conduct a brake test.•Check for brush or branches caught in the
undercarriage. They could increase the possibility of
a fire, as well as cut fuel and / or brake lines,
puncture rubber bellows of the axles or drive shafts.
Wa r n i n g !
If you feel a sudden significant vibration or ride
disturbance, or you suspect that possible damage to
your vehicle has occurred, you should turn on the
hazard warning flashers, carefully slow down, and
drive with caution to an area which is a safe
distance from the roadway.Inspect the tires and under the vehicle for possible
damage. If the vehicle or tires appear unsafe, have
it towed to the nearest Mercedes-Benz Light Truck
Center or tire dealer for repairs.

198 Driving systems
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Notes:
If the engine does not brake the vehicle sufficiently
while driving on a downgrade, the speed you set on the
cruise control may be exceeded. In this case the
automatic transmission shifts down (max. to 3rd gear)
to maintain the set cruise control speed by using the
engine’s braking power.
As soon as the grade eases, the automatic transmission
shifts up again dependent on the selector lever position.
Nevertheless, in some cases you may have to step on the
b ra ke pe dal to slow d own. In t his case t he cruise control
is switched off.
Use the lever to resume the previously set speed.Transmission in LOW RANGE mode
The cruise control should not be activated during off-
road driving in the LOW RANGE mode. Doing so could
reduce driving comfort.
Trailer operation
When towing a trailer, do not allow engine speed to drop
too low on inclines. Select a lower range (“3”, “2” or “1”)
in time, depending on the degree of the incline. This is
also valid with cruise control activated.
At extreme inclines switch to LOW RANGE mode, see
page 209.
Note:
For detailed information see trailer towing on page 190.

201 Driving systems
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cluster displayPractical hints Car care Index Antilock brake system (ABS)
Important!
The ABS improves steering control of the vehicle during
hard braking maneuvers.
The ABS prevents the wheels from locking up above a
vehicle speed of approximately 5 mph (8 km / h)
independent of road surface conditions.
At the instant one of the wheels is about to lock up, a
slight pulsation can be felt in the brake pedal,
indicating that the ABS is in the regulating mode. Keep
firm and steady pressure on the brake pedal while
experiencing the pulsation.
Continuous steady brake pedal pressure results in
applying the advantages of the ABS, namely braking
power and ability to steer the vehicle.In the case of an emergency brake maneuver keep
continuous full pressure on the brake pedal. In this
manner only can the ABS be most effective.
On slippery road surfaces, the ABS will respond even
with light brake pedal pressure because of the
increased likelihood of locking wheels. The pulsating
brake pedal can be an indication of hazardous road
conditions and functions as a reminder to take extra
care while driving.
ABS control
The ABS malfunction indicator lamp- in the
instrument cluster comes on with the key in steering
lock position 2 and should go out with the engine
running.
When the ABS malfunction indicator lamp- in the
instrument cluster comes on while the engine is
running, it indicates that the ABS has detected a
malfunction and has switched off. In this case, the brake
system functions in the usual manner, but without
antilock assistance.
With the ABS malfunctioning, the BAS, EBP, ESP and
4-ETS+ are also switched off. The malfunction indicator
lamps come on with the engine running.
Wa r n i n g !
Do not pump the brake pedal, rather use firm,
steady brake pedal pressure. Pumping the brake
pedal defeats the purpose for ABS and significantly
reduces braking effectiveness.

202 Driving systems
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If the charging voltage falls below 10 volts, the
malfunction indicator lamp comes on and the ABS is
switched off. When the voltage is above this value again,
the malfunction indicator lamp should go out and the
ABS is operational.
If the ABS malfunction indicator lamp stays illuminated,
have the system checked at your authorized
Mercedes-Benz Light Truck Center as soon as possible.Notes:
To alert following vehicles to slippery road conditions
you discover, operate your hazard warning flashers as
appropriate.
Operating the vehicle on a single axle dynamometer
should only be done for briefly testing the brakes. To do
so, move selector lever to position “N”. The engine must
be shut off (key in steering lock position 0 or 1).
LOW RANGE – ABS
During off-road driving a special low range system for
the antilock brake system (ABS) is operational with
transmission in LOW RANGE mode, see page 211.
When applying the service brakes at speeds below
approximately 18 mph (30 km / h), the front wheels are
locked cyclically to shorten the braking distance (dig in
effect). This affects steering the vehicle.
Wa r n i n g !
ABS cannot prevent the natural laws of physics
from acting on the vehicle, nor can it increase
braking or steering efficiency beyond that afforded
by the condition of the vehicle brakes and tires or
the traction afforded. The ABS cannot prevent
accidents, including those resulting from excessive
speed in turns, following another vehicle too
closely, or aquaplaning. Only a safe, attentive, and
skillful driver can prevent accidents. The
capabilities of an ABS equipped vehicle must never
be exploited in a reckless or dangerous manner
which could jeopardize the user’s safety or the
safety of others.

204 Driving systems
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Note:
In winter operation, the maximum effectiveness of the
electronic traction system is only achieved with
Mercedes-Benz recommended M+S rated radial-ply tires
and / or snow chains.
LOW RANGE – 4-ETS+
During off-road driving a special low range system for
the four wheel electronic traction system (4-ETS+) is
operational with transmission in LOW RANGE mode,
see page 211.
If one or more tires lose traction while driving downhill
(accelerator released), the 4-ETS+ engages and the
warning lampv, located in the speedometer dial,
starts to f lash.Electronic brake proportioning (EBP)
The EBP enhances braking effectiveness by allowing the
rear brakes to supply a greater proportion of the braking
effort without a loss of vehicle stability.
If a warning tone sounds for five seconds and the
symbols É and - are displayed in the instrument
cluster, the system has detected a malfunction and is
switched off. Have the system checked immediately at
an authorized Mercedes-Benz Light Truck Center.
Failure to do so could result in an accident, since the
enhanced braking effect is not available when the
system is switched off.
Note:
When the EBP is switched off, every time the engine is
started, a warning tone will sound for five seconds and
the symbols É and - will light up. In addition,
whenever the brakes are applied at speeds exceeding
25 mph (40 km / h), the warning tone sounds for five
seconds.

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If one drive wheel loses traction and begins to spin, the
brake is applied until the wheel regains sufficient
traction.
Note:
Avoid spinning of one drive wheel. This may cause
serious damage to the drive train which is not covered
by the Mercedes-Benz Limited Warranty.
The ESP warning lamp, located in the speedometer dial,
starts to f lash at any vehicle speed as soon as the tires
lose traction and the wheels begin to spin.
To return to the enhanced vehicle stability offered by
ESP: press lower half of the switch (the ESP warning
lamp in the speedometer dial goes out).
Important!
If the ESP warning lamp f lashes:
•during take-off, apply as little throttle as possible,
•while driving, ease up on the accelerator.LOW RANGE – ESP
During off-road driving a special low range system for
the electronic stability program (ESP) is operational
with transmission in LOW RANGE mode, see page 211.
In the LOW RANGE mode the electronic stability
program (ESP) operates in a traction improving fashion
specifically adapted for off-road driving. At speeds
below 27 mph (45 km / h) the ESP assists in over-/
understeering, thus improving vehicle tracking.