2006 MERCEDES-BENZ ML350 Coolant

226 Controls in detail3-zone automatic climate control*Deactivating
It is possible to deactivate the air condi-
tioning (cooling) function of the automatic
climate control system. The air in the vehi-
cle will then no longer be cooled or dehu-
midified.
Press button2 (
page 218).
The indicator lamp on button2
goes out.
The cooling function switches off after
a short delay.Activating
Moist air can fog up the windows. You can
dehumidify the air with the air condition-
ing.

Press button2 again.
The indicator lamp on button2
comes on.
The air conditioning system uses the refrig-
erant R-134a. This refrigerant is free of
CFCs which are harmful to the ozone layer.
Residual heat and ventilation
With the engine switched off, it is possible
to continue to heat or ventilate the interior
for up to 30 minutes. This feature makes
use of the residual heat produced by the
engine.
!If the air conditioning cannot be turned
on again, this indicates that the air
conditioning is losing refrigerant. The
compressor has turned itself off.
Have the air conditioning checked at
the nearest authorized Mercedes-Benz
Light Truck Center.
iHow long the system will provide heat-
ing depends on the coolant tempera-
ture and the battery voltage.
Regardless of the temperature and air
volume set on the climate control panel
an interior temperature is aimed at by
72°F (22°C) and the blower runs for
the protection of the battery on low
stage.

227 Controls in detail
3-zone automatic climate control*
Activating
Turn the SmartKey in the starter switch
to position0 or1 (
page 34), or re-
move it from the starter switch.

Press buttonT (
page 218).
The indicator lamp on buttonT
comes on.
Deactivating

Press buttonT.
The indicator lamp on buttonT
goes out.
Rear air conditioning1Left rear center air vent, adjustable
2Right rear center air vent, adjustable
3Temperature control
4Air distribution and air volume
(automatic, manual)
5Air distribution (directs air through
both center air vents)
6Air distribution (directs air through the
footwells and side air vents)
7Rear air conditioning on/off
8Decrease air volume
9Increase air volume
Activating rear air conditioning

Press buttonU.
The indicator lamp on buttonU
comes on. The temperature, air volume
and air distribution are adjusted
automatically.
iThe residual heat is automatically
turned off:

when the ignition is switched on


after about 30 minutes


if the coolant temperature is too
low


if the battery voltage drops

318 OperationDriving instructions

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 automatic transmission in1,
switch on off-road driving program
(page 248).


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 engine coolant rises to an ex-
tremely high temperature (coolant tem-
perature needle approaching the red
zone) when the air conditioning is on,
turn off the air conditioning system.
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 re-
turn to your lane.Uncoupling the trailer

Start the engine (
page 34).

Make sure the automatic transmission
is set toP.

Set the parking brake for the vehicle
(page 52) and for the trailer.

Close all doors and the tailgate.
Detach the trailer immediately after-
ward as follows:

Disconnect all electrical plug connec-
tors.

Uncouple the trailer.
!If the trailer should begin to sway, re-
duce the vehicle’s speed immediately.
In no case attempt to straighten out the
tow vehicle and trailer by increasing
the speed.

322 OperationDriving instructionsCoolant temperature
During severe operating conditions,
e.g. stop-and-go traffic, the coolant tem-
perature may rise close to approximately
248°F (120°C).
The engine should not be operated with
the coolant temperature over 248°F
(120°C). Doing so may cause serious en-
gine damage 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 the
engine has cooled down.

324 OperationAt the gas station
Replace the fuel cap by turning it
clockwise until it audibly engages.

Close the fuel filler flap.
Check regularly and before a long trip
Open the hood (
page 326).
Example ML 5001Brake fluid
2Coolant level
3Windshield washer system and
headlamp cleaning system*
Engine oil level
For more information on engine oil, see
“Engine oil” (
page 327).Brake fluid
Coolant
For normal replenishing, use water (pota-
ble water quality).
For more information, see “Coolant level”
(
page 332) and see “Fuels, coolants, lu-
bricants, etc.” (
page 493).
iOnly use premium unleaded gasoline
with a minimum Posted Octane Rating
of 91 (average of 96 RON/86 MON).
Information on gasoline quality can
normally be found on the fuel pump.
For more information on gasoline, see
the Factory Approved Service Products
pamphlet.iLeaving the engine running and the fuel
cap open can cause the yellow engine
malfunction indicator lamp
?(USA only), ±(Canada only)
to illuminate.
For more information, see “Practical
hints” (
page 385).
!If you find that the brake fluid in the
brake fluid reservoir has fallen to the
minimum mark or below, have the
brake system checked for brake pad
thickness and leaks immediately. Noti-
fy an authorized Mercedes-Benz Light
Truck Center immediately. Do not add
brake fluid as this will not solve the
problem. For more information, see
“Practical hints” (
page 381).


327 Operation
Engine compartment
Closing
Let the hood drop from a height of
approximately 1ft (30cm).
The hood will lock audibly.

Check to make sure 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
higher engine speeds
Engine oil consumption checks should only
be made after the vehicle break-in period.
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.
iDo not use any special lubricant addi-
tives, as these may damage the drive
assemblies. Using special additives not
approved by Mercedes-Benz may
cause damage not covered by the
Mercedes-Benz Limited Warranty.
More information on this subject is
available at any Mercedes-Benz Light
Truck Center.

332 OperationEngine compartment
Unscrew filler cap1 from filler neck.

Add engine oil as required. Be careful
not to overfill with oil.
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.

Screw filler cap1 back on filler neck.
For more information on engine oil, see
“Technical data” (
page 481).
Transmission 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 level
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.
!Excess 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.
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 coolant temperature is
above 158°F (70°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
1/2 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.

333 Operation
Engine compartment
The coolant expansion tank is located on
the driver’s side of the engine compart-
ment.
1Coolant expansion tank

Using a rag, turn the cap slowly approx-
imately one half turn to the left to re-
lease any excess pressure.

Continue turning the cap to the left and
remove it.
The coolant level is correct if the level

for cold coolant: reaches the top of
the indicator wall visible through
the filling opening


for warm coolant: is approximately
0.6 in (1.5 cm) higher

Add coolant as required.

Replace and tighten cap.
For more information on coolant, see the
“Technical data” section (
page 497).Windshield/rear window washer
system and headlamp cleaning
system*
The windshield washer reservoir is located
in the engine compartment.
1Cap
Fluid for the windshield washer system and
the headlamp cleaning system* is supplied
from the windshield washer reservoir. It
has a capacity of 8.1 US qt (7.7 l).