Page 943 of 4133

139 Controls in detail
Automatic climate control
Activating
Press buttonÄ (
page 135).
The indicator lamp on the button
comes on.
Deactivating
Press buttonÄ (
page 135).
The indicator lamp on the button goes
out.
Air conditioning
The air conditioning is operational while
the engine is running and cools the interior
air to the temperature set by the operator.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 button° (
page 135).
The indicator lamp on the button°
comes on.
Activating
Moist air can fog up the windows. You can
dehumidify the air with the air condition-
ing.
Press button° again.
The indicator lamp on the button°
goes out.
The air conditioning system uses the refrig-
erant R-134a. This refrigerant is free of
CFCs which are harmful to the ozone layer.
iTo achieve the fastest possible cooling
of the interior, the automatic climate
control automatically switches to air
recirculation. The indicator lamp in the
buttonÄ is not illuminated when
the system automatically switches to
air recirculation.
iThe air recirculation mode is
deactivated automatically
after 30 minutes if the automatic
climate control is switched on
after five minutes if the air condi-
tioning is switched off
after five minutes if the outside
temperature is above approximate-
ly 45°F (7 °C)
iCondensation may drip out from under-
neath the vehicle. This is normal and
not an indication of a malfunction.
Page 944 of 4133

140 Controls in detailAutomatic climate control
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.
Activating
Turn the key in the steering lock to
position0 or1 (
page 33).
Press button° (
page 135).
The indicator lamp on button°
comes on.Deactivating
Press button°.
The indicator lamp on button°
goes out.
!If the °button on the automatic
climate control panel starts to flash,
this indicates that the air conditioning
system is losing refrigerant. The com-
pressor has turned itself off. The air
conditioning cannot be turned on
again.
Have the air conditioning system
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 temperature set in the
climate control. The blower will run at
lower speed regardless of the air vol-
ume control setting.
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
Page 1014 of 4133

210 OperationDriving instructions
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 gear selector lever in position1,
switch transfer case to LOW RANGE
mode (
page 125).
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.
!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 overstee-
ring and stepping on the brakes.
Page 1097 of 4133
293 Technical data
Layout of poly-V-belt drive
Layout of poly-V-belt drive
1Automatic belt tensioner
2Power steering pump
3Air conditioning compressor
4Crankshaft
5Coolant pump
6Generator (alternator)
7Idler pulley
Page 1105 of 4133
301 Technical data
Fuels, coolants, lubricants etc.
Model
Capacity
Fuels, coolants, lubricants etc.
Cooling system
approx. 12.7 US qt (12.0 l)
MB Anticorrosion / Antifreeze
Fuel tank
ML 350, ML 500
22.0 US gal (83.0 l)
Premium unleaded gasoline:
Posted Octane 91 (Avg. of 96 RON / 86 MON
including a reserve of
approx. 3.2 US gal (12.0 l)
Air conditioning system
R-134a refrigerant and special PAG lubricant
oil (never R-12)
Windshield washer and
headlamp cleaning
system*
8.0 US qt (7.6 l)
MB Windshield Washer Concentrate
1
1Use MB Windshield Washer Concentrate “S” and water for temperatures above freezing or MB Windshield Washer Concentrate “S” and commercially available pre-
mixed windshield washer solvent / antifreeze for temperatures below freezing. Follow suggested mixing ratios (page 307).
Page 1106 of 4133

302 Technical dataFuels, coolants, lubricants etc.Engine oils
Engine oils are specifically tested for their
suitability in our engines. Therefore, use
only engine oils approved by
Mercedes-Benz. Information on approved
engine oils is available in the Factory
Approved Service Products pamphlet, or at
your authorized Mercedes-Benz Light
Truck Center.
Engine oil additives
Do not blend oil additives with engine oil.
They may damage the engine.
Damage or malfunctions resulting from
blending oil additives are not covered by
the Mercedes-Benz Limited Warranty.Air conditioning refrigerant
R-134a (HFC) refrigerant and special PAG
lubricating oil is used in the air condition-
ing system.
Never use R-12 (CFC) or mineral-based lu-
bricating oil. Otherwise damage to the
system will occur.
Brake fluid
During vehicle operation, the boiling point
of the brake fluid is continuously reduced
through the absorption of moisture from
the atmosphere. Under extremely strenu-
ous operating conditions, this moisture
content can lead to the formation of bub-
bles in the system, thus reducing the sys-
tem’s efficiency.
Therefore, the brake fluid must be re-
placed every two years, preferably in the
spring.
Only brake fluid approved by
Mercedes-Benz is recommended. Your au-
thorized Mercedes-Benz Light Truck
Center will provide you with additional in-
formation.
!Always check the oil filler cap
(page 221) for important information
pertaining to the engine oil needing to
meet a specific Mercedes-Benz specifi-
cation (e.g. MB 229.5). If such informa-
tion is printed on the oil filler cap, only
use an engine oil from the list of ap-
proved engine oils in the Factory Ap-
proved Service Products pamphlet that
meets the specification indicated on
the oil filler cap.
Using engine oils of other specification
may cause the FSS to incorrectly deter-
mine the next service interval and will
result in engine damage not covered by
the Mercedes-Benz Limited Warranty.
Page 1121 of 4133

317 Index
A
ABS 25, 76, 311
ABS control 76
LOW RANGE mode 77
Malfunction indicator lamp 242
Warning lamp 242
Accelerator position, automatic
transmission 123
Accident
In case of 52
Activating
Air circulation mode 139
Air recirculation mode 139
Anti-theft alarm system 83
Automatic climate control 135
ESP 82
Exterior headlamps 48
Hazard warning flasher 112
Headlamps 48
High beams 110
Ignition 33Immobilizer 54, 83
Rear passenger compartment ventila-
tion and climate control 141
Rear window defroster 133
Rear window wiper 51
Residual heat 140
Seat heater* 98
Tow-away alarm 85
Warning indicators (Parktronic*) 155
Windshield wipers 50
Activating automatic central locking 93
Adding
Coolant 223
Engine oil 221
Additional turn signals 266
Adjustable steering column
Indicator lamp 253
Adjusting 34
Backrest tilt 36, 38
Exterior rear view mirror 40
Head restraint height 36, 38Head restraint tilt 37, 39
Headlamp aim 272
Instrument cluster illumination 116
Manual seat 35
Mirrors 40
Power seats* 37
Seat cushion tilt 38
Seat fore and aft 35
Seat fore and aft adjustment 37
Seat height 36, 38
Seats 34
Steering wheel 39
Adjusting air distribution
Automatic climate control 137
Adjusting air volume
Automatic climate control 137
Air conditioner (cooling)
Turning on 139
Air conditioning
Cooling 139
Page 1122 of 4133

318 IndexAir conditioning refrigerant 302
Air outlets
Automatic climate control 142
Air pressure see Tire inflation
pressure 227
Air recirculation mode 138
Activating 139
Deactivating 139
AIRBAG OFF
Warning lamp 243
Airbags 59
BabySmart
TM airbag deactivation
system 311
BabySmartTM deactivation
system 70
Children 60
Front 63
Passenger 63
Safety guidelines 62
Side impact 64
Window curtain 64Alarm
Audible 75, 84, 86
Canceling 84, 86
Visual 83
Alarm system
Anti-theft 83
Anticorrosion/antifreeze 305
Antiglare
Automatic 126
Antilock brake system (ABS) 311
Anti-theft alarm system
Arming 83
Canceling alarm 84, 86
Disarming 84
Anti-theft systems
Anti-theft alarm system 83
Immobilizer 83
Tow-away alarm, glass breakage
sensor 84
Aquaplaning see Hydroplaning 197
Armrest
Storage compartment in front of 165
Storage spaces 165Armrest in rear seat bench 167
Ashtray
Front center console 168
Rear center console 169
ATF (automatic transmission fluid) 222
Attaching a trailer 208
Automatic antiglare for rear view
mirror 126
Automatic central locking
Activating 93
Deactivating 93
Automatic climate control 134
Adjusting air distribution 137
Adjusting air volume 137
Air conditioning 139
Air outlets 142
Air recirculation mode 138
Basic setting 137
Changing basic setting 137
Defrosting 138
Economy mode 135