1997 MERCEDES-BENZ ML320 engine overheat

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.

124 Controls in detailAutomatic transmissionTowing a trailer
If you tow a trailer, note the following
points:

Manually shift to a lower gear range
(4,3, 2, 1), if the transmission hunts
between gears on inclines
(page 121).
A lower gear range and reduction of
speed reduces the change to overload
or overheat the engine.


At very steep inclines switch transfer
case to LOW RANGE mode
(page 125).
For more information on trailer towing, see
the “Operation” section (
page 206).Emergency operation (Limp Home
Mode)
If vehicle acceleration worsens or the
transmission no longer shifts, the trans-
mission is most likely operating in limp
home (emergency operation) mode. In this
mode only second gear and reverse gear
can be activated.
Stop the vehicle.

Move gear selector lever to positionP.

Turn off the engine.

Wait at least ten seconds before
restarting.

Restart the engine.

Move selector lever to positionD
(for second gear) orR.

Have the transmission checked at an
authorized Mercedes-Benz Light Truck
Center as soon as possible.

195 Operation
Driving instructions
Install only brake pads and brake fluid
recommended by Mercedes-Benz.
After hard braking, it is advisable to drive
on for some time, rather than immediately
parking, so the air stream will cool down
the brakes faster.
Driving off
Apply the brakes to test them briefly after
driving off. Perform this procedure only
when the road is clear of other traffic.
Warm up the engine smoothly. Do not
place full load on the engine until the oper-
ating temperature has been reached.
When starting off on a slippery surface, do
not allow a drive wheel to spin for an ex-
tended period with the ESP switched off.
Doing so may cause serious damage to the
drivetrain which is not covered by the
Mercedes-Benz Limited Warranty.
Warning!
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.
!When driving down long and steep
grades, relieve the load on the brakes
by shifting into a lower gear to use the
engine’s braking power. This helps
prevent overheating of the brakes and
reduces brake pad wear.