engine MERCEDES-BENZ ML320 1997 Complete Owner's Manual

79 Instrument cluster
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index If the “CHECK ENGINE” malfunction
indicator lamp comes on when the engine is
running, it indicates a malfunction of the
fuel management system, emission control
system, systems which impact emissions, or
the fuel cap is not closed tight. In all cases,
we recommend that you have the
malfunction checked as soon as possible, see
page 218.Additional function indicator lamps
(in the odometer display)
FSS indicator (Service A), see page 87
FSS indicator (Service B), see page 87
The symbols appear in the main odometer display field
prior to the next suggested service. Depending on
operating conditions throughout the year, the next
service is calculated and displayed in days or distance
remaining. See page 87 for notes on the flexible service
system (FSS).
CHECK
ENGINE

81 Instrument cluster
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Coolant temperature gauge
During severe operating conditions and stop-and-go city
traffic, the coolant temperature may rise close to the red
marking.
The engine should not be operated with the coolant
temperature in the red zone. Doing so may cause
serious engine damage which is not covered by the
Mercedes-Benz Limited Warranty.
Wa r n i n g !
• Driving when your engine is badly overheated
can cause some fluids which may have leaked
into the engine compartment to catch fire. You
could be seriously burned.• Steam from an overheated engine can cause
serious burns and can occur just by opening
the engine hood. Stay away from the engine if
you see or hear steam coming from it.Turn off the engine, get out of the vehicle and do
not stand near the vehicle until it cools down.

82 Instrument cluster
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Outside temperature indicator
The temperature sensor is located in the front bumper
area. Due to its location, the sensor can be affected by
road or engine heat during idling or slow driving. This
means that the accuracy of the displayed temperature
can only be verified by comparison to a thermometer
placed next to the sensor, not by comparison to external
displays (e.g. bank signs etc.).
Adaptation to ambient temperature takes place in steps
and depends on the prevailing driving conditions (stop-
and-go or moderate, constant driving) and amount of
temperature change.Tachometer
The tachometer displays the present engine speed in
revolutions per minute (RPM).
To help protect the engine, the fuel supply is interrupted
if the engine is operated above its specified limit.
Wa r n i n g !
The outside temperature indicator is not designed
to serve as an Ice-Warning Device and is therefore
unsuitable for that purpose. Indicated
temperatures just above the freezing point do not
guarantee that the road surface is free of ice.

83 Trip computer
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Trip computer (standard; optional on model ML 320)
The trip computer is located in the overhead console.
Function keys are:
•RESET
•MODE
Note:
With engine not running, the display switches off
automatically 30 seconds after the last entry.To select a mode:
With key in steering lock position 1 or 2, press MODE
key repeatedly to illuminate the display and scroll
through menu for one of the following options:
1. Date, see page 84.
2. Compass, see page 84.
3. Stop watch, see page 86.
4. Present fuel consumption – displays miles per
gallon or liters pe r 100 km.
5. Average fuel consumption – displays miles per
gallon or liters per 100 km, see page 86.
6. Distance remaining with fuel presently in tank.
Note:
The display f lashes when fuel supply drops to the
reserve level. The distance remaining is no longer
shown.
7. Language – Press RESET key until the desired
language is displayed. Depending on language
selected, information is displayed in that country’s
customary system. See page 86.
8. Trip computer switched off.
MODE

86 Trip computer
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
To calibrate the compass:
If the vehicle was exposed to a significant magnetic
zone, such as high voltage power lines, the compass
may have to be calibrated.
Calibration of the compass should be done in an area
free of steel superstructures and power lines. All
electrical consumers (e.g. exterior lamps, climate
control, etc.) should be switched off, doors and liftgate
closed. Do not open or close the roof. An open door or
liftgate triggers the display “–––”.
1. Start and run the engine.
2. Press MODE key repeatedly until the compass
display appears in the trip computer display.
3. Press RESET key to select the compass zone display.
4. Press RESET repeatedly until the correct zone, as
determined from the zone map (see page 85), is
shown in the display.
5. Press MODE key, “CAL–” appears in the display.
6. Press and hold RESET for a minimum of 2 seconds.7. Without interruption drive two or more full circles
at a speed between 3 mph (5 km / h) and 7 mph
(10 km / h) during which the message “CAL” is
replaced with a compass bearing (e.g. N, SW etc.),
immediately followed by three full circles at the
same speed, with only the rear window defroster
switched on. The defroster can be switched off
again. The calibration of the compass is now
complete.
•Stop watch –
Press RESET key to start the count. Press again to
stop the count. Press and hold RESET key to reset
sto p watch.
•Average fuel consumption –
Press RESET key to delete present reading.
•Language –
Press RESET key to set the language used in the
display.

88 Flexible service system
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Important!
The FSS indicator is not an engine oil level indicator.
See page 89 for engine oil level indicator.
Notes:
When disconnecting vehicle battery for one or more
days at a time, such days will not be counted. Any such
days not counted by the FSS can be added by your
Mercedes-Benz Light Truck Center.
The interval between services is determined by the type
of driving for which the vehicle is used. For example,
driving at extreme speeds, and cold starts combined
with short distance driving in which the engine does not
reach normal operating temperature, reduce the interval
between services.
Following a completed A or B service the Mercedes-
Benz Light Truck Center sets the counter mileage to
10 000 miles (Canada: 15 000 km) and 365 days.
The counter can also be set by any individual. To do so:
1. Turn the key in steering lock to position 2.
2. Immediately press button (1) twice within one
second.3. The present status for days or distance is displayed.
Within 10 seconds turn key in steering lock to
position 0.
4. Press and hold button (1), while turning key in
steering lock to position 2 again. The present status
for days or distance is displayed once more.
Continue to hold button (1).
After approximately 10 seconds a signal sounds, and
the display shows 10 000 miles (Canada: 15 000 km)
for approximately 10 seconds.
5. Release button (1).
If the FSS counter was inadvertently reset, have it
corrected at a Mercedes-Benz Light Truck Center.
Notes:
The FSS allows for distances between 10 000 miles
(Canada: 15 000 km) and 20 000 miles (Canada:
30 000 km), or from 365 to 730 days between services.
However you choose to set your reference numbers, the
scheduled services as posted in the Service Booklet
must be followed to properly care for your vehicle.

89 Engine oil level indicator
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Engine oil level indicator
To check the engine oil level, park vehicle on level
ground, with engine at normal operational temperature.
Check oil level approximately 5 minutes after stopping
the engine, allowing for the oil to return to the oil pan.
Turn the key in steering lock to position 2 and wait until
the display “––––––” appears in the odometer display
field.
Within 1 second press button (1) twice.The following messages are available:
“OIL i.O”
No oil needs to be added.
“–1.0 L”
“–1.5 L”
“–2.0 L”
Add oil to upper (max) mark of the dipstick.
See page 233 for instructions on adding engine oil.
“OIL HI”
Do not overfill the engine.
Excessive oil must be siphoned or drained off. It could
cause damage to the engine and catalytic converter not
covered by the Mercedes-Benz Limited Warranty.
The display “––––––” flashes in the odometer display
field if a proper oil level check cannot be performed. The
engine oil level check can be repeated after a short time.
Perform the engine oil level check with the dipstick, if it
cannot be completed via the odometer display field.
See page 233.
In this case we recommend that you have the system
checked at a Mercedes-Benz Light Truck Center.

90 Exterior lamp switch
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Exterior lamp switch
Rotate switch $ to positions:
DOff
CParking lamps (also side marker lamps, taillamps,
license plate lamps, instrument panel lamps)
Canada only: When the engine is running, the low
beam is additionally switched on.
õParking lamps plus low beam or high beam
headlamps (switch pushed forward)ƒStanding lamps, left or right side (depending on
turn signal switch position). Turn key in steering
lock to position 0 or remove.
Standing lamps, left – move stalk to position (5).
Standing lamps, right – move stalk to position (4).
Move stalk to positions:
1Low beam (exterior lamp switch position õ)
2High beam (exterior lamp switch position õ)
3High beam flasher (high beam available
independent of exterior lamp switch position)
4Turn signals, right
5Turn signals, left
To signal minor directional changes, such as changing
lanes on a h ig hway, m ove exterior la mp sw itch b rief ly to
the point of resistance only and release. The turn
signals blink three times.
To operate the turn signals continuously, move the
exterior lamp switch past the point of resistance (up or
down). The switch is automatically canceled when the
steering wheel is turned to a large enough degree.

91 Exterior lamp switch
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Turn signal failure
If one of the turn signals fails, the turn signal indicator
system f lashes and sounds at a faster than normal rate.
Standing lamps
When the vehicle is parked on the street the standing
lamps (right or left side parking lamps) can be turned
on, making the vehicle more visible to passing vehicles.
The standing lamps cannot be operated with the key in
steering lock position 1 or 2.
Note:
With the key removed and a front door open, a warning
sounds if the vehicle’s exterior lamps (except standing
lamps) are not switched off.Daytime running lamps (Canada only)
When the engine is running and the selector lever is in
a driving position, the low beam headlamps (includes
parking lamps, side marker lamps, taillamps and
license plate lamps) are automatically switched on.
When shifting from a driving position to position “N”
or “P”, the low beam switches off (2 seconds delay).
For nighttime driving the exterior lamp switch should
be turned to position õ to permit activation of the
high beam headlamps.

99 Climate control
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index 1Air volume control switch
2Temperature selector switch
3Air distribution switch
4Air recirculation
5Air conditioning mode
6Air volume control for center air outlets,
turn wheel up to open.
7Air volume control for side air outlet,
turn wheel up to open.
8Center air outlets, adjustable
9Side air outlets, adjustable
10Windshield air outlets
11Floor outlets
The air conditioning mode only operates with the œ
button pushed, the air volume control switch set to
position 1 to 4, and the engine running.To quickly cool down the passenger compartment, turn
temperature selector switch fully to the left to
positionO. Turn temperature selector to maintain
desired temperature.
The air conditioning mode removes considerable
moisture from the air during operation in the cooling
mode. It is normal for water to drip on the ground
through ducts in the underbody.
Important!
This vehicle is equipped with an air conditioner system
that uses R–134a (HFC: hydrof luorocarbon) as a
refrigerant. Repairs should always be performed by a
qualified technician, and refrigerant should be collected
in a recovery system for recycling.
Note:
For the air flow-through system to function properly, the
air vents, located in the left and right side rear
passenger compartment trim panel covers, should be
ke pt un obst ru cte d .