1997 MERCEDES-BENZ ML430 engine overheat

223 Malfunction and indicator lamps
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
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.

224 Malfunction and indicator lamps
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cluster displayPractical 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
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cluster displayPractical hintsCar 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 controlsOperation DrivingInstrument
cluster displayPractical hintsCar 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 controlsOperation DrivingInstrument
cluster displayPractical hintsCar 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 controlsOperation DrivingInstrument
cluster displayPractical hints Car careIndex 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 ............................................................ 221ETR (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

81
Instrument cluster
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data
Instruments
and controls Operation
Driving Instrument
cluster display Practical 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.

160
Catalytic converter
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data
Instruments
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Driving Instrument
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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.