engine overheat MERCEDES-BENZ ML350 2003 W163 Owner's Manual

74 Safety and SecurityDriving and safety systems
LOW RANGE 4-ETS
During off-road driving a special low range
system for the 4-ETS is operational with
transmission in LOW RANGE mode.
More information can be found in the
“Practical hints” section (
page 224) and
(
page 226).
EBP
The EBP enhances braking effectiveness
by allowing the rear brakes to supply a
greater proportion of the braking effort
without a loss of vehicle stability.
Warning!
G
When you see the 4-ETS/ESP-warning lamp v
flashing in the speedometer dial, 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 result-
ing from excessive speed.
!The engine must be shut off when

the parking brake is being tested on
a brake test dynamometer.


the vehicle is being towed with the
front axle raised.
Otherwise, the 4-ETS will engage the
brakes and seriously damage the brake
system.
iIf the yellow 4-ETS malfunction indica-
tor lamp
{
comes on while the
4-ETS/ESP warning lamp
v
flashes,
the electronic traction system is being
switched off temporarily to prevent
overheating of the drive wheel brakes.

111 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 instrument
cluster (
page 110).
The display changes between main
odometer and trip odometer.

Press the left knob1 twice.
The next scheduled service is displayed
(page 215).
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 it
cools down.

117 Controls in detail
Automatic transmission
Accelerator position
Your driving style influences the transmis-
sion’s shifting behavior:
Less throttle Earlier upshifting
More throttle Later upshifting
Kickdown
Use kickdown when you want maximum
acceleration
Press the accelerator past the point of
resistance.
The transmission shifts into a lower
gear.

Ease on the accelerator when you have
reached the desired speed.
The transmission shifts up again.

Towing 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 114).
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 118).
For more information on trailer towing, see
the “Operation” section (
page 192).Emergency operation (Limp Home
Mode)
If the vehicle acceleration worsens or the
transmission no longer shifts, the trans-
mission is most likely operating in limp
home mode. In this mode only 2nd gear
and reverse gear can be activated.
Stop the vehicle.

Move selector lever to positionP.

Turn off the engine.

Wait at least ten seconds before re-
starting.

Move selector lever to position D (for
2nd gear) or R.

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

181 Operation
Driving instructions
Install only brake pads and brake fluid rec-
ommended 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 one 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.

195 Operation
Driving instructions
Adjust the mirrors to permit unobstructed
view beyond rear of trailer.

If the trailer has electric brakes, start
your vehicle and trailer moving slowly,
and then apply only the trailer brake
controller by hand to be sure the
brakes are working properly.


Always secure items in the trailer to
prevent load shifts while driving.


When towing a trailer, check occasion-
ally to be sure that the load is secure,
and that lighting and trailer brakes (if
so equipped) are functioning properly.


Take into consideration that when tow-
ing a trailer, the handling characteris-
tics are different and less stable from
those when operating the vehicle with-
out a trailer.
It is important to avoid sudden maneu-
vers.


The vehicle and trailer combination is
heavier, and therefore is limited in ac-
celeration and climbing ability, and re-
quires longer stopping distances.
I t i s m o r e p r o n e t o r e a c t i n g t o s i d e w i n d
gusts, and requires more sensitive
steering input.


If possible, do not brake abruptly, but
rather engage the brake slightly at first
to permit the trailer to activate its
brake. Then increase the braking force.


If the transmission hunts between
gears on inclines, manually shift to a
lower gear (select 4, 3, 2 or 1).
A lower gear and reduction of speed re-
duces the chance of engine overload-
ing and / or overheating.


On very steep inclines, not manageable
with selector lever in position1, switch
transfer case to LOW RANGE mode
(page 118).


When going down a long hill, shift into
a lower gear and use the engine’s brak-
ing effect.
Avoid riding the brakes, thus overheat-
ing the vehicle and trailer brakes.
!If the trailer should begin to sway, re-
duce the vehicle’s speed and use the
brake controller by hand to straighten
out the vehicle and trailer.
In no case should you attempt to
straighten out the tow vehicle and trail-
er by increasing the speed or over-
steering and stepping on the brakes.

198 OperationDriving instructionsCatalytic converter
Your Mercedes-Benz is equipped with
monolithic type catalytic converters, an
important element in conjunction with the
oxygen sensors to achieve substantial con-
trol of the pollutants in the exhaust emis-
sions. Keep your vehicle in proper
operating condition by following our rec-
ommended maintenance instructions as
outlined in your Service Booklet.
Emission control
Certain engine systems serve to keep the
toxic components of the exhaust gases
within permissible legal limits.
These systems, of course, will function
properly only when maintained strictly ac-
cording to factory specifications. Any ad-
justments on the engine should, therefore,
be carried out only by qualified
Mercedes-Benz Light Truck Center autho-
rized technicians. Engine adjustments
should not be altered in any way. More-
over, the specified service jobs must be carried out regularly according to
Mercedes-Benz servicing requirements.
For details refer to the Service Booklet.
!To prevent damage to the catalytic con-
verters, 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 and start a fire.
Warning!
G
As with any vehicle, do not idle, park or op-
erate this vehicle in areas where combusti-
ble 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.
Warning!
G
Inhalation of exhaust gas is hazardous to
your health. All exhaust gas contains carbon
monoxide, and inhaling it can cause uncon-
sciousness and lead to death.
Do not run the engine in confined areas
(such as a garage) which are not properly
ventilated. If you think that exhaust gas
fumes are entering the vehicle while driving,
have the cause determined and corrected
immediately. If you must drive under these
conditions, drive only with at least one win-
dow fully open at all times.

199 Operation
Driving instructions
Coolant temperature
During severe operating conditions and
stop-and-go city traffic, the coolant tem-
perature may rise to approx. 248°F
(120°C).
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.
Warning!
G


Driving when your engine is badly over-
heated can cause some fluids which
may have leaked into the engine com-
partment to catch fire. You could be se-
riously 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.

203 Operation
Engine compartment
Closing
Let the hood drop from a height of ap-
proximately 1ft (30cm).
The hood will lock audibly.

Check to make sure that the hood is
fully closed.
If you can raise the hood at a point
above the headlamps, then it is not
properly closed. Open it again and let it
drop with somewhat greater force.
Engine oil
The amount of oil your engine needs will
depend on a number of factors, including
driving style. Higher oil consumption can
occur when

the vehicle is new


the vehicle is driven frequently at high-
er engine speeds.
Engine oil consumption checks should only
be made after the vehicle break-in period.
Checking engine oil level
When checking the oil level the vehicle
must


be parked on level ground


be at normal operating temperature


have been stationary for at least five
minutes with the engine turned off
Warning!
G
If you see flames or smoke coming from the
engine compartment, or if the coolant tem-
perature 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 the fire department.Warning!
G
The engine is equipped with a transistorized
ignition system. Because of the high voltage
it is dangerous to touch any components (ig-
nition 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
Warning!
G
Be careful that you do not close the hood on
anyone.!Do not push the hood closed manually,
as this could damage it.

206 OperationEngine compartmentTransmission fluid level
The transmission fluid level does not need
to be checked. If you notice transmission
fluid loss or gear shifting malfunctions,
have an authorized Mercedes-Benz Light
Truck Center check the automatic trans-
mission.Coolant
The engine coolant is a mixture of water
and anticorrosion/antifreeze. To check
the coolant level, the vehicle must be
parked on level ground and the engine
must be cool. 1Cap
2COLD LEVEL mark
The coolant level should reach the COLD
LEVEL mark2 in the reservoir.

Using a rag, turn the cap slowly approx-
imately one half turn to the left to re-
lease any excess pressure.
Warning!
G
In order to avoid any possibly serious burns:

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 indi-
cates 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 the cap approx-
imately ½ turn to relieve excess pres-
sure. If opened immediately, scalding
hot fluid and steam will be blown out un-
der pressure.


Do not spill antifreeze on hot engine
parts. Antifreeze contains ethylene gly-
col which may burn if it comes into con-
tact with hot engine parts.
iIf the engine is already at its regular op-
erating temperature, the coolant may
be approximately 0.6 in (1.5 cm) above
the COLD LEVEL mark.


226 Practical hintsWhat to do if …¿
The yellow malfunction indicator
lamp comes on while driving.
The BAS or ESP is malfunctioning.
It is possible that the engine output will be re-
duced.

Have the BAS/ESP checked at an au-
thorized Mercedes-Benz Light Truck
Center as soon as possible.
{
The yellow malfunction indicator
lamp comes on while driving.
4-ETS has switched off to prevent overheat-
ing of the brakes. Also see 4-ETS/ESP warn-
ing lamp (
page 224).
As soon as the brakes have cooled off,
4-ETS switches on again.
The indicator lamp goes out.
4-ETS is malfunctioning and has switched off.

Have the 4-ETS checked at your au-
thorized Mercedes-Benz Light Truck
Center as soon as possible.
ê
The yellow LOW RANGE indicator
lamp blinks after one or more
switching conditions.
The gear selection conditions have not been
adhered to.

Repeat the gear selection process
(page 118).
ê
The yellow LOW RANGE indicator
lamp blinks after switching the
ignition on.
LOW RANGE mode is malfunctioning.
Have the LOW RANGE mode checked at
your authorized Mercedes-Benz Light
Truck Center.
Problem
Possible cause
Suggested solution