engine overheat MERCEDES-BENZ ML350 1997 Complete Owner's Manual

195
Driving instructions
Te ch n ica l
data
Instruments
and controls Operation
Driving Instrument
cluster display Practical 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.

203
Driving systems
Te ch n ica l
data
Instruments
and controls Operation
Driving Instrument
cluster display Practical hints Car care Index
Four-wheel electronic traction system (4-ETS+)
With the key in steering lock position 2, the yellow
4-ETS+ malfunction indicator lamp { and the 4-ETS+
warning lamp v come on and should go out when
the engine is running.
The 4-ETS+ improves vehicle’s ability to utilize available
traction, especially under slippery road conditions. The
brakes are applied to the spinning wheel and power is
transferred to the wheel(s) with traction.
The 4-ETS+ warning lamp v, located in the
speedometer dial, starts to flash at any vehicle speed, as
soon as the tires lose traction and the wheels begin to
spin.
Important!
If the 4-ETS+ warning lamp v flashes:
• during take-off, apply as little throttle as possible,
• while driving, ease up on the accelerator.
Adapt your speed and driving to the prevailing road
conditions. 4-ETS+ Control
If the yellow 4-ETS+ malfunction indicator lamp {
comes on while the 4-ETS+ warning lamp v flashes,
the electronic traction system is being switched off
temporarily to prevent overheating of the drive wheel
brakes.
If the 4-ETS+ malfunction indicator lamp { comes on
with the engine running, a malfunction has been
detected.
Have the 4-ETS+ checked at your authorized
Mercedes-Benz Light Truck Center as soon as possible.
With the ABS malfunctioning, the 4-ETS+ is also
switched off.
Caution!
If the vehicle is towed with the front axle raised (see
towing the vehicle on page 255), or when testing the
parking brake on a brake test dynamometer, the engine
must be shut off (key in steering lock position 0 or 1).
Otherwise, the electronic traction system will
immediately be engaged and will apply the rear wheel
brakes.

223
Malfunction and indicator lamps
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical 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.

224
Malfunction and indicator lamps
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints Car care Index
Low engine oil level warning lamp With the key in steering lock position 2, the
oil level warning lamp comes on and should
go out when the engine is running.
If the warning lamp does not go out after starting the
engine, or comes on with the engine running and at
operating temperature, the engine oil level has dropped
to approximately the minimum mark on the dipstick.
When this occurs, the warning lamp will first come on
intermittently and then stay on if the oil level drops
further.
If no oil leaks are noted, continue to drive to the nearest
service station where the engine oil should be topped to
the “full” mark on the dipstick with an approved oil.
The low engine oil level warning light should not be
ignored. Extended driving with the light illuminated
could result in serious engine damage that is not
covered by the Mercedes-Benz Limited Warranty.
In addition to the warning lamp, the engine oil level
should be periodically checked with the dipstick or via
the oil level indicator in the odometer display field, for
example during a fuel stop, or before a long trip (see
engine oil level indicator on page 89 and checking
engine oil on page 233). Low engine coolant level warning
When the coolant level warning lamp comes
on while driving, then the coolant level has
dropped below the required level, or the
coolant temperature is in the red zone. If no leaks are
noticeable and the engine temperature does not
increase, continue to drive to the nearest service station
and have coolant added to the coolant system, see
page 234. If the engine temperature reaches the red
zone, move vehicle to an area which is in a safe distance
from the roadway and turn off the engine. Also see
coolant temperature gauge on page 81.
The low engine coolant level warning should not be
ignored. Extended driving with the symbol displayed
may cause serious engine damage not covered by the
Mercedes-Benz Limited Warranty.
In cases of major or frequent minor coolant loss, have
the cooling system checked at your authorized
Mercedes-Benz Light Truck Center as soon as possible.
Notes:
Do not drive without coolant in the cooling system. The
engine will overheat causing major engine damage.
Monitor the coolant temperature gauge while driving.

232
Engine compartment
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints
Car care Index
Wa r n i n g !
To help prevent personal injury, stay clear of
moving parts when the hood is open and the engine
is running. Be sure the hood is properly closed
before driving. When closing hood, use extreme
caution not to catch hands or fingers.The radiator fan may continue to run for
approximately 30 seconds or even restart after the
engine has been turned off. Stay clear from fan
blades.
The engine is equipped with a transistorized
ignition system. Because of the high voltage it is
dangerous to touch any components (ignition coils,
spark plug sockets, diagnostic socket) of the
ignition system
• with the engine running,
• while starting the engine,
• if ignition is “on” and the engine is turned manually.If you see flames, steam or smoke coming from the
engine compartment, or if the coolant temperature
gauge indicates that the engine is overheated, do
not open the hood. Move away from vehicle and do
not open the hood until the engine has cooled. If
necessary, call a fire department.

235
Engine compartment
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints
Car care Index
Adding coolant
If coolant has to be added, a 50 / 50 mixture of water and
MB anticorrosion / antifreeze should be added.
After adding coolant, close cap until you hear it click a
few times.
The drain plugs for the cooling system are located on
the left and right side of the engine block directly above
the engine mounts and at the bottom of the radiator.
Anticorrosion / antifreeze mixture, see page 297.
Wa r n i n g !
In order to avoid possible serious burns or injury: • Use extreme caution when opening the hood if there are any signs of steam or coolant leaking
from the cooling system, or if the coolant
temperature gauge indicates that the coolant is
overheated.
• Do not remove pressure cap on coolant reservoir if engine temperature is above 194 °F
(90 °C). Allow engine to cool down before
removing cap. The coolant reservoir contains
hot fluid and is under pressure.• Using a rag, slowly open cap approximately 1/2 turn to relieve excess pressure. If opened
immediately, scalding hot fluid and steam will
be blown out under pressure.• Do not spill antifreeze on hot engine parts. Antifreeze contains ethylene glycol which may
burn if it comes into contact with hot engine
parts.

251
Battery
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints
Car care Index
If a tire constantly loses air, it should be inspected for
damage.
The spare tire should be checked periodically for
condition and inflation. Spare tire will age and become
worn over time even if never used, and thus should be
inspected and replaced when necessary. Battery
Important!
Battery replacement information:
The maintenance-free battery is located in the engine
compartment.
The service life of the battery is dependent on its
condition of charge. The battery should always be kept
sufficiently charged, in order to last an optimum length
of time.
Wa r n i n g !
Do not overinflate tires. Overinflating tires can
result in sudden deflation (blowout) because they
are more likely to become punctured or damaged
by road debris, potholes etc.. Follow recommended
inflation pressures.Do not overload the tires by exceeding the specified
vehicle capacity weight (as indicated by the label
on the driver’s door latch post). Overloading the
tires can overheat them, possibly causing a
blowout.
Wa r n i n g !
Failure to follow these instructions can result in
severe injury or death.Never lean over batteries while connecting, you
might get injured.Battery fluid contains sulfuric acid. Do not allow
this fluid to come in contact with eyes, skin or
clothing. In case it does, immediately flush affected
area with water and seek medical help if necessary.A battery will also produce hydrogen gas, which is
flammable and explosive. Keep flames or sparks
away from battery, avoid improper connection of
jumper cables, smoking etc..

303
Index
Te ch n ica l
data
Instruments
and controls Operation Driving
Instrument
cluster display Practical hints Car care
Index
Emission control label ..................................................285
Engine compartment ..................................................... 231
Engine malfunction CHECK ENGINE malfunction indicator lamp ....... 218
Engine oil additives .......................................................294
Engine oil consumption ................................................234
Engine oil level Checking ............................................................. 89, 233
Warning ......................................................................224
Engine oil level indicator ................................................ 89
Engine oils ......................................................................294 Capacities ...................................................................292
Low engine oil level warning ..................................224
Engine overheating ......................................................... 81
Engine speed limit Overrevving ................................................................. 82
Enlarged cargo area ....................................................... 131
Entrance lamps ...............................................................112
ESP LOW RANGE — ESP ..................................................208
ESP (Electronic stability program) ..............................205 Control switch ...........................................................207
Malfunction indicator lamp ..................................... 221
Synchronizing ...........................................................206
Warning lamp ............................................................ 221 ETR (Emergency tensioning retractor) .........................55
ETS (4-ETS+) .................................................................. 203 LOW RANGE – 4-ETS+ ............................................ 204
Exterior lamp switch .......................................................90
Exterior lamps ............................................................... 260 Adjusting headlamp aim ......................................... 268
Auxiliary fog lamp ............................................. 92, 264
Fog lamps .....................................................................93
Headlamp assembly ......................................... 261, 262
Headlamps .................................90, 261, 262, 268, 280
High mounted stop lamp ......................................... 267
License plate lamps ................................................. 267
Low and high beam ............................................90, 263
Parking lamp ...................................................... 90, 264
Replacing bulbs ........................................................ 260
Side marker lamp ..................................................... 264
Standing lamp .....................................................90, 264
Taillamp assemblies ................................................ 265
Turn signal lamp ................................................90, 264
Turn signal lamp, side ............................................. 266
Exterior rear view mirrors ..............................................73 Electrically folding ...................................................... 75

79 Safety and Security
Driving and safety systems
4-ETS
The 4-Electronic Traction System (4-ETS)
improves vehicle’s ability to utilize avail-
able traction, especially under slippery
road conditions. The brakes are applied to
the spinning wheel and power is trans-
ferred to the wheel(s) with traction.
The traction control engages at vehicle
speeds up to approximately 24 mph
(40 km / h), and switches off at approxi-
mately 50 mph (80 km / h).
The {indicator lamp in the instrument
cluster (
page 25) comes on when you
turn the key to position2. It goes out when
the engine is running.
The 4-ETS / ESP warning lampv, loca-
ted in the speedometer dial, starts to flash
at any vehicle speed, as soon as the tires
lose traction and the wheels begin to spin.
Warning!
G
When you see the 4-ETS / ESP-warning
lampv flashing in the speedometer,
then proceed as follows:

While driving off, apply as little throttle
as possible.


While driving ease up on the accelera-
tor.


Adapt your speed and driving style to
the prevailing road conditions.
Failure to observe these guidelines could
cause the vehicle to skid.
The 4-ETS cannot prevent accidents resul-
ting from excessive speed.
!Because of the ESP’s automatic opera-
tion, the engine must be shut off
(SmartKey in starter switch position0
or1) when the parking brake is being
tested on a brake test dynamometer.
Active braking action through ESP may
otherwise seriously damage the front
or rear axle brake system.
Operational tests with the engine
running can only be conducted on a
two-axle dynamometer.iIf the yellow 4-ETS malfunction indica-
tor lamp{ comes on while the
4-ETS / ESP warning lampv flash-
es, the electronic traction system is be-
ing switched off temporarily to prevent
overheating of the drive wheel brakes.

117 Controls in detail
Instrument cluster
Coolant temperature gauge
Under normal driving conditions, the cool-
ant temperature may rise to 248°F
(120°C). The coolant temperature may
climb to the red marking:

at high outside temperatures


during stop-and-go city traffic


when driving on hilly terrain
The engine should not be operated with
the coolant temperature in the red zone.
Doing so may cause serious engine dam-
age which is not covered by the
Mercedes-Benz Limited Warranty.
Display in the speedometer
Changing display
Press the left knob1 in the instru-
ment cluster (
page 116).
The display changes between main
odometer and trip odometer.

Press the left knob1 twice.
The next scheduled service is displayed
(page 232).
Warning!
G
Driving when your engine is badly overheat-
ed 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 the
engine has cooled down.