O2 sensor MERCEDES-BENZ C240 2005 W203 Owner's Manual

51 Getting started
Driving
Windshield wipers
The combination switch is located on the
left of the steering column.Combination switch1Single wipe
2Switching on windshield wipers 
Switch on ignition (
page 33).Switching on windshield wipers

Turn the combination switch to the
desired position depending on the
intensity of the rain.
0Windshield wipers off
IIntermittent wiping
IINormal wiper speed
IIIFast wiper speediVehicles without rain sensor:
When the vehicle is standing still, the
wiper speed returns to next lower
setting.
Vehicles with rain sensor*:
Intermittent wiping interval is
dependent on wetness of windshield.
After the initial wipe, pauses between
wipes are automatically controlled by
the rain sensor.
!Vehicles with rain sensor*:
Do not leave windshield wipers in
intermittent setting when the vehicle is
taken to an automatic car wash or
during windshield cleaning. Wipers will
operate in the presence of water
sprayed on the windshield, and wipers
may be damaged as a result.
The switch should not be left in
intermittent setting as the wipers will
wipe the windshield once every time
the engine is started. Dust that
accumulates on the windshield might
scratch the glass and/or damage the
wiper blades when wiping occurs on a
dry windshield.

120 Controls in detailInstrument clusterThe outside temperature is indicated in the
multifunction display (
page 121). For
information on how to select the unit of the
indicated temperature, i.e. degrees
Celsius (°C) or degrees Fahrenheit (°F),
see “Selecting temperature display mode”
(
page 135).The temperature sensor is located in the
front bumper area. Due to its location, the
sensor can be affected by road or engine
heat during idling or slow driving. This
means that the accuracy of the displayed
temperature can only be verified by com-
parison to a thermometer placed next to
the sensor, not by comparison to external
displays (e.g. bank signs, etc.).When moving the vehicle into colder ambi-
ent temperatures (e.g. when leaving your
garage), you will notice a delay before the
lower temperature is displayed.
A delay also occurs when ambient temper-
atures rise. This prevents inaccurate tem-
perature indications caused by heat
radiated from the engine during idling or
slow driving.

169 Controls in detail
Good visibility
Automatic antiglare rear view mirrors*
The reflection brightness of the exterior
rear view mirror on the driver’s side and
the interior rear view mirror will respond
automatically to glare when

the ignition is switched on
and


incoming light from headlamps falls on
the sensor in the interior rear view
mirror.
The rear view mirror will not react if


reverse gearR is engaged


the interior lighting is turned on
Warning!
G
The automatic antiglare function does not
react if incoming light is not aimed directly
at sensors in the interior rear view mirror.
The interior rear view mirror and the exterior
rear view mirror on the driver’s side do not
react, for example, if the rear window
sunshade* is in raised position.
Glare can endanger you and others.Warning!
G
In the case of an accident liquid electrolyte
may escape from the mirror housing if the
mirror glass breaks.
Electrolyte has an irritating effect. Do not
allow the liquid to come into contact with
eyes, skin, clothing, or respiratory system.
In case it does, immediately flush affected
area with water, and seek medical help if
necessary.
Warning!
G
Exercise care when using the passen-
ger-side exterior rear view mirror. The mirror
surface is convex (outwardly curved surface
for a wider field of view). Objects in mirror
are closer than they appear. Check your
interior rear view mirror or glance over your
shoulder before changing lanes.!Electrolyte drops coming into contact
with the vehicle paint finish can be
completely removed only while in the
liquid state and by applying plenty of
water.

225 Controls in detail
Power windows
Stopping windows
Press or pull respective switch again.Opening and closing the windows with
the SmartKey
The tilt/sliding sunroof* (
page 229) will
also be opened or closed when the power
windows are operated with the SmartKey .
!If the upward movement of the window
is blocked during the closing
procedure, the window will stop and
open slightly.
Remove the obstruction, pull the
switch again past the resistance point
and release.
If the window still does not close when
there is no obstruction, then pull and
hold the switch again. The side window
will then close without the obstruction
sensor function
Warning!
G
Driver’s door only:
If within five seconds you again pull the
switch past the resistance point and
release, the automatic reversal will not
function.
Warning!
G
Never operate the windows or tilt/sliding
sunroof* if there is the possibility of anyone
being harmed by the opening or closing pro-
cedure.
In the event that the procedure causes
potential danger, the procedure can be
immediately halted by releasing the
transmit button on the SmartKey. To reverse
direction of movement, press buttonŒ
for opening or‹ for closing.

273 Operation
Driving instructions
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 Maintenance Booklet.
Emission control
Certain systems of the engine serve to
keep the toxic components of the exhaust
gases within permissible limits required by
law.
These systems, of course, will function
properly only when maintained strictly
according to factory specifications. Any
adjustments on the engine should,
therefore, be carried out only by qualified
Mercedes-Benz Center authorized techni-
cians. Engine adjustments should not be
altered in any way. Moreover, the specified
service jobs must be carried out regularly
according to Mercedes-Benz servicing
requirements. For details refer to the
Maintenance Booklet.
!To prevent damage to the catalytic
converters, only use 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
operate this vehicle in areas where combus-
tible 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.

321 Practical hints
What to do if …
When the message
At next gas station
add 1.0 qt engine oil
(Canada:
1.0 l
)
appears while the engine is running and at
operating temperature, the engine oil level
has dropped to approximately the mini-
mum level.When this occurs, the warning will first
come on intermittently and then stay on if
the oil level drops further.
Visually check for oil leaks. If no obvious oil
leaks are noted, drive to the nearest
service station where the engine oil should
be topped to the required level with an
approved oil specified in the Factory
Approved Service Products pamphlet.
Display symbol
Display messages
Possible cause
Suggested solution
:
Engine oil level
Visit workshop.
The engine oil has dropped to a critical
level.

Check the engine oil level
(page 280) and add oil as required
(page 281).

If you must add engine oil frequently,
have the engine checked for possible
leaks.
Oil sensor malfunction
Visit workshop.
The measuring system is malfunctioning.

Have the measuring system checked
by an authorized Mercedes-Benz
Center.!The engine oil level warnings should
not be ignored. Extended driving with
the symbol displayed could result in
serious engine damage that is not
covered by the Mercedes-Benz Limited
Warranty.

324 Practical hintsWhat to do if …Display symbol
Display message
Possible cause
Possible solution
.
High beam left
The left high beam lamp is
malfunctioning.

Replace the bulb as soon as possible.
High beam right
The right high beam lamp is
malfunctioning.

Replace the bulb as soon as possible.
License plate lamp,
left
The left license plate lamp is
malfunctioning.

Replace the bulb as soon as possible.
License plate lamp,
right
The right license plate lamp is
malfunctioning.

Replace the bulb as soon as possible.
Light sensor
Drive to workshop
The lamp sensor is malfunctioning.
The headlamps switch on automatically.

In the control system, set lamp
operation to manual (
page 142).

Switch on the headlamps using the
exterior lamp switch (
page 109).

Visit an authorized Mercedes-Benz
Center as soon as possible.
Low beam left
The left low beam lamp is malfunctioning.
Halogen headlamp:
Replace the bulb as soon as possible.
Bi-Xenon* headlamp:

Visit an authorized Mercedes-Benz
Center as soon as possible.

399 Technical terms
ABS
(A
ntilock B
rake S
ystem)
Prevents the wheels from locking up
during braking so that the vehicle can
continue to be steered.
Alignment bolt
Metal pin with thread. The centering
pin is an aid used when changing a tire
to align the wheel with the wheel hub.
BabySmart
TM1
air bag deactivation
system
This system detects if a special system
compatible child restraint seat is
installed on the front passenger seat.
The system will automatically
deactivate the passenger front air bag
when such a seat is properly installed
(the56indicator lamp located
in the center console comes on). See
an authorized Mercedes-Benz Center
for availability. BabySmart
TM compatible child seats
Special restraint system for children.
The sensor system for the passenger
seat prevents deployment of the
passenger front air bag if a
BabySmartTM compatible child seat is
installed.
BAS
(B
rake A
ssist S
ystem)
System for potentially reducing braking
distances in emergency braking
situations. The system is activated
when it senses an emergency based on
how fast the brake is applied.
Bi-Xenon headlamps*
Headlamps which use an electric arc as
the light source and produce a more
intense light than filament headlamps.
Bi-Xenon headlamps produce low
beam and high beam.CAC
(C
ustomer A
ssistance C
enter)
Mercedes-Benz customer service
center, which can help you with any
questions about your vehicle and
provide assistance in the event of a
breakdown.
CAN system
(C
ontroller A
rea N
etwork)
Data bus network serving to control
vehicle functions such as door locking
or windshield wiping depending on
vehicle settings and/or ambient
conditions.
Cockpit
All instruments, switches, buttons and
indicator/warning lamps in the
passenger compartment needed for
vehicle operation and monitoring.
1BabySmart
TM is a trademark of Siemens
Automotive Corp.

419 Index
Key, SmartKey
Battery check lamp 89
Checking the batteries 91
Factory setting 89
Global locking 89
Global unlocking 89
Loss of 91
Messages in display 322
Positions in starter switch 33
Remote control 88
Restoring to factory setting 90
Selective setting 89
Starting the engine,
automatic transmission* 47
Starting the engine,
manual transmission 46
Turning off the engine 56
Unlocking the trunk lid 91
Unlocking with 32
Kickdown 163, 401
Kilometers/miles in speedometer 135
Km/h or mph in speedometer 135L
Labels, identification 376
Lamp bulbs, exterior 344
Lamp sensor
Message in display 324
Lamps, exterior
Front 345
Light sensor 324
Messages in display 323–326
Rear 345
Lamps, indicator and warning
ABS 25, 302
Battery (SmartKey) 89
Brakes 25, 303
Engine diagnostics 304, 307
Engine malfunction 25, 304–305
ESP 25, 306
Front fog lamps 109
Front passenger
front air bag off 27, 63, 70, 308
Fuel reserve 25, 307
High beam headlamps 25Instrument cluster 302–307
Low beam headlamps 25
Maintenance service indicator 292
Rear fog lamp 109
Seat belt telltale 25, 307
SRS 25, 59, 307
Turn signals 25
Language
Multifunction display 136
Setting 136
LATCH-type child seat anchors 73
Folding back 74
Layout of poly-V-belt drive 377
Leather upholstery
Cleaning 299
Lever for voice control system* 23
License plate lamps
Messages in display 324
Replacing bulbs 345
Light alloy wheels
Cleaning 298
Technical data 381, 382

420 IndexLight sensor 324
Lighter see Cigarette lighter
Lighting 109
Automatic headlamp mode 110
Combination switch 113
Daytime running lamp mode 111
Door entry lamps 116
Exterior lamp switch 109
Front fog lamps 112
High beams 113
Instrument cluster illumination 117
Instruments 117
Interior 115
Locator lighting 112
Low beam 109
Manual headlamp mode 110
Night security illumination 112
Parking lamps 109
Rear fog lamp 113
Settings (control system) 141
Standing lamps 109
Trunk lamp 116Limiting the gear range 159
Limp Home Mode 167
Loading 234
Cargo tie-down rings* 240
Instructions 239
Roof rack* 234
Split rear bench seat* 237
Locator lighting 112
Setting 143
Lock button 401
Locking 54, 88
Automatic while driving 96
Centrally from inside 96
Fuel filler flap 275
Global, SmartKey 89
Glove box 241
Vehicle in an emergency 338
Loss of keys 91
Loss of Service and Warranty
Information Booklet 375
Low beam headlamps
Indicator lamp 25
Messages in display 324–325
Replacing bulbs 345, 347
Switching on 49Lowering
Vehicle 359
Lubricants
Technical data 387
M
Main dimensions 385
Main fuse box
In passenger compartment 370
Mainodometer 121
Maintenance 12, 292
Vehicles with E85 fuel 393
Maintenance service
Calling up the maintenance
service indicator 293
Major service (Service B) 292
Minor service (Service A) 292
Overdue 293
Types 293
When due 292
Maintenance service indicator 292
Calling up 293, 294
Clearing 293, 294
Maintenance System
(U.S. vehicles) 292, 401