air condition MERCEDES-BENZ ML320 1997 Complete User Guide

102 Climate control
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Windshield fogged up on outside.
Switch on wiper motor.
Set air distribution control switch to positiond
ora.
Dust filter
Nearly all dust particles and pollen are filtered out
before outside air enters the passenger compartment
through the air distribution system.
Note:
Keep the air intake grille in front of windshield free of
snow and debris.
Climate control – OFF
To switch the climate control off, set air volume control
switch to position0.
Switch off air conditioning mode œ. Control lamp in
button goes out.Air recirculation
This mode can be selected to temporarily reduce the
entry of annoying odors or dust into the vehicle’s
interior.
Outside air is not supplied to the vehicles’s interior.
To select, press O button. Indicator lamp in button
lights up.
To cancel, press O button again. Indicator lamp in
button goes out.
If the windows should fog up from the inside, switch
from recirculated air back to fresh air.

160 Catalytic converter
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Catalytic converter
Your Mercedes-Benz is equipped with monolithic type
catalytic converters, an important element in
conjunction with the oxygen sensors to achieve
substantial control of the pollutants in the exhaust
emissions. Keep your vehicle in proper operating
condition by following our recommended maintenance
instructions as outlined in your Service Booklet.Caution!
To prevent damage to the catalytic converters, use only
premium unleaded gasoline in this vehicle.
Any noticeable irregularities in engine operation should
be repaired promptly. Otherwise, excessive unburned
fuel may reach the catalytic converter causing it to
overheat, which could start a fire.
Wa r n i n g !
As with any vehicle, do not idle, park or operate
this vehicle in areas where combustible materials
such as grass, hay or leaves can come into contact
with the hot exhaust system, as these materials
could be ignited and cause a vehicle fire.

174 Driving instructions
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Driving instructions
Drive sensibly – save fuel
Fuel consumption, to a great extent, depends on driving
habits and operating conditions.
To save fuel you should:
•keep tires at the recommended inflation pressures,
•remove unnecessary loads,
•remove roof rack when not in use,
•allow engine to warm up under low load use,
•avoid frequent acceleration and deceleration,
•have all maintenance work performed at regular
intervals by an authorized Mercedes-Benz Light
Truck Center.
Fuel consumption is also increased by driving in cold
weather, in stop-and-go traffic, on short trips and in hilly
country.Drinking and driving
Pedals
Wa r n i n g !
Drinking or taking drugs and driving can be a very
dangerous combination. Even a small amount of
alcohol or drugs can affect your reflexes,
perceptions and judgement.The possibility of a serious or even fatal accident is
sharply increased when you drink or take drugs
and drive.Please don’t drink or take drugs and drive or allow
anyone to drive after drinking or taking drugs.Wa r n i n g !
Keep driver’s foot area clear at all times. Objects
stored in this area may impair pedal movement.

175 Driving instructions
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BrakesThe condition of the parking brake system is checked
each time the vehicle is in the shop for the required
maintenance service.
If the parking brake is released and the brake warning
lamp in the instrument cluster stays on and there is no
audible warning (EBP), the brake fluid level in the
reservoir is too low.
Brake pad wear or a leak in the system may be the
reason for low brake f luid in the reservoir.
Have the brake system inspected at an authorized
Mercedes-Benz Light Truck Center immediately.
All checks and service work on the brake system should
be carried out by an authorized Mercedes-Benz Light
Truck Center.
Install only brake pads and brake fluid recommended by
Mercedes-Benz.
Wa r n i n g !
When the engine is not running, the brake and
steering systems are without power assistance.
Under these circumstances, a much greater effort is
necessary to stop or steer the vehicle.Wa r n i n g !
After driving in heavy rain for some time without
applying the brakes or through water deep enough
to wet brake components, the first braking action
may be somewhat reduced and increased pedal
pressure may be necessary to obtain expected
braking effect. Be sure to maintain a safe distance
from vehicles in front.Resting your foot on the brake pedal will cause
excessive and premature wear of the brake pads.It can also result in the brakes overheating thereby
significantly reducing their effectiveness. It may
not be possible to stop the vehicle in sufficient time
to avoid an accident.
Wa r n i n g !
If other than recommended brake pads are
installed, or other than recommended brake fluid
is used, the braking properties of the vehicle can be
degraded to an extent that safe braking is
substantially impaired. This could result in an
accident.

177 Driving instructions
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Tread wear indicators (TWI) are required by law. These
indicators are located in six places on the tread
circumference and become visible at a tread depth of
approximately
1/16in (1.5 mm), at which point the tire is
considered worn and should be replaced.
The tread wear indicator appears as a solid band across
the tread.
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 f lashers, 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.
Wa r n i n g !
Do not allow your tires to wear down too far. As
tread depth approaches
1/16in (1.5 mm), the
adhesion properties on a wet road are sharply
reduced.
Depending upon the weather and / or road surface
(conditions), the tire traction varies widely.

180 Driving instructions
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Winter 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 position “N”. Try to keep the vehicle
under control by corrective steering action.
Caution!
Do not use LOW RANGE mode 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.
Road salts and chemicals can adversely affect 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. A prerequisite is, however, that this be done
without endangering other drivers on the road.If the vehicle is parked after being driven on salt treated
roads, the braking efficiency should be tested as soon as
possible after driving is resumed while observing the
safety rules in the previous paragraph.
Wa r n i n 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 engine running.
Otherwise, deadly carbon monoxide (CO) gases may
enter vehicle interior resulting in unconsciousness
and death.To assure sufficient fresh air ventilation, open a
window slightly on the side of the vehicle not
facing the wind.

195 Driving instructions
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cluster displayPractical hints Car care Index At very steep inclines, not manageable with selector
lever in position “1”, switch transfer case to LOW
RANGE, see page 209 for instructions on how to engage
LOW RANGE.
When going down a long hill, shift into a lower gear and
use the engine’s braking effect. Avoid riding the brakes,
thus overheating the vehicle and trailer brakes.
If the engine coolant rises to an extremely high
temperature (coolant temperature needle approaching
the red zone) when the air conditioner is on, turn off the
air conditioner. Engine coolant heat can be additionally
vented by opening the windows, switching the climate
control fan speed to high and setting the temperature
control to the maximum hot position.
Extreme care must be exercised since your vehicle with
a trailer will require additional passing distance ahead
than when driving without a trailer. Because your
vehicle and trailer is longer than your vehicle alone, you
will also need to go much farther ahead of the passed
vehicle before you can return to your lane.Parking
Wa r n i n g !
To reduce the risk of personal injury, or damage to
the vehicle powertrain, as a result of vehicle/trailer
movement, always:1. Keep right foot on brake pedal.2. Shift gear selector lever to position “N”.3. Have a second person place wheel chocks on
downhill side of left and right trailer wheels.4. Slowly release brake pedal and let vehicle and
trailer roll into chocks until stopped.5. Firmly depress parking brake pedal.6. Move gear selector lever to position “P”.7. On inclines turn front wheels towards the road
curb.

213 What you should know at the gas station
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cluster displayPractical hints Car care Index Leaving the engine running and the fuel cap open can
cause the “CHECK ENGINE” lamp to illuminate.
Fuel tank capacity approximately 19.0 US gal (72.0 l).
This includes approximately 3.2 US gal (12.0 l) reserve.
Use premium unleaded gasoline: Posted Octane
Index 91 (Average of 96 RON / 86 MON).
•Engine oil
Engine oil level check, see page 89 and page 233.
Fill quantity between upper and lower dipstick
marking level: 2.1 US qt (2.0 l).
Recommended engine oils, see Approved Service
Products sheet.• Coolant
For normal replenishing, use water (potable water
quality).
For further information (e.g. anticorrosion/
antifreeze), see page 292.
• Spark plugs
Approved spark plugs, see page 290.
• Tire pressure
For tire pressure, refer to tire pressure label inside
the fuel filler flap. See page 250 for further details.
• Air conditioner
R-134a refrigerant and special PAG lubricant, see
page 294.
Wa r n i n g !
Overfilling of fuel tank may result in creating
pressure in the system which could cause a gas
discharge such as the gas spraying back out upon
removing the filler nozzle which could cause
personal injury.

223 Malfunction and indicator lamps
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cluster displayPractical hints Car care Index Seat belt warning lamp
With the key in steering lock position 2, the
seat belt warning lamp comes on for a short
time if the driver’s seat belt is not fastened.
After starting the engine, the warning lamp remains
illuminated for a short time to remind the driver and
passengers to fasten seat belts.
Charge indicator lamp
Should the charge indicator lamp fail to
come on prior to starting when the key is in
steering lock position 2 or should it fail to go
out after starting or during operation, this indicates a
malfunction which must be repaired at an authorized
Mercedes-Benz Light Truck Center immediately.If the charge indicator lamp comes on while the engine
is running, this may indicate that the poly-V-belt has
broken. Should this condition occur, the poly-V-belt
must be replaced before continuing to operate the
vehicle. Otherwise, the engine will overheat due to an
inoperative water pump which may result in damage to
the engine.
Do not continue to drive the vehicle with the charge
indicator lamp illuminated. Doing so could result in
serious engine damage that is not covered by the
Mercedes-Benz Limited Warranty.

250 Tires, Wheels
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Tire inflation pressure
A table (see fuel filler flap) lists the tire inflation
pressures specified for Mercedes-Benz recommended
tires as well as for the varying operating conditions.
Important!
Tire pressure changes by approximately 1.5 psi (0.1 bar)
per 18°F (10°C) of air temperature change. Keep this in
mind when checking tire pressure inside a garage –
especially in the winter.
Example:
If garage temperature = approximately +68°F (+20°C)
and ambient temperature = approximately +32°F (0°C)
then the adjusted air pressure = specified air pressure
+3 psi (+0.2 bar).Tire pressures listed for light loads are minimum values
offering high driving comfort. Increased inflation
pressures for heavy loads produce favorable handling
characteristics with lighter loads and are perfectly
permissible. The ride of the vehicle, however, will
become somewhat harder.
Tire temperature and pressure increase with the vehicle
speed. Tire pressure should therefore only be checked
and corrected on cold tires. Correct tire pressure in
warm tires only if pressure has dropped below the
pressure listed in the table and the respective operating
conditions are taken into consideration.
An underinf lated tire due to a slow leak (e.g. due to a
nail in the tire) may cause damage such as tread
separation, bulging etc.. Regular tire pressure checks
(including the spare tire) at intervals of no more than
14 days are therefore essential.