reset MERCEDES-BENZ C300 4MATIC 2008 W204 Owner's Manual

Contents
At the gas station .............................. 322
Refueling ...................................... 322
Check regularly and
before a long trip.......................... 324
Engine compartment ......................... 325
Hood ............................................ 325
Engine oil ..................................... 327
Transmission fluid level ................ 328
Coolant level ................................ 329
Windshield washer system and
headlamp cleaning system* ......... 330
Tires and wheels ................................ 331
Important guidelines .................... 331
Tire care and maintenance........... 332
Direction of rotation ..................... 334
Loading the vehicle ...................... 334
Recommended tire
inflation pressure ......................... 339
Checking tire inflation pressure ... 341
Tire labeling.................................. 348
Load identification ....................... 352
DOT,
Tire Identification Number (TIN) ... 352
Maximum tire load ....................... 353
Maximum tire inflation pressure .. 354Uniform Tire Quality Grading
Standards (U.S. vehicles) .............. 354
Tire ply material ............................ 356
Tire and loading terminology......... 356
Rotating tires ................................ 359
Winter driving ..................................... 360
Winter tires ................................... 360
Snow chains.................................. 361
Maintenance....................................... 362
Maintenance
service indicator message ............ 362
Calling up the maintenance
service indicator display ............... 363
Resetting the maintenance
service indicator ........................... 363
Vehicle care........................................ 364
Cleaning and care of vehicle ......... 364
Practical hints.................................. 373
What to do if …? ................................. 374
Lamps in instrument cluster ......... 374
Air bag off indicator lamp ............. 385
Vehicle status messages in
the multifunction display .............. 387
Where will I find ...? ............................ 420
First aid kit.................................... 420
Vehicle jack, vehicle tool kit,
luggage bowl, Minispare wheel ..... 420
Unlocking/locking in an emergency .. 424
Unlocking the vehicle ................... 424
Locking the vehicle ....................... 425
Fuel filler flap ................................ 426
Manually unlocking the
transmission gear selector lever ... 426
Resetting activated head restraints.... 427
Replacing SmartKey batteries ............ 428
Replacing bulbs .................................. 430
Bulbs............................................. 431
Replacing bulbs for front lamps .... 432
Replacing bulbs for rear lamps ..... 436
Replacing wiper blades ...................... 438
Removing wiper blades ................. 439
Installing wiper blades .................. 439

37 Safety and Security
Occupant safety

Always sit as upright as possible, prop-
erly use the seat belts and use an appro-
priately sized infant restraint, toddler
restraint, or booster seat recommended
for the size and weight of the child.
Failure to follow these instructions can
result in severe injuries to you or other
occupants.
If you sell your vehicle, it is important that
you make the buyer aware of this safety
information. Be sure to give the buyer this
Operator’s Manual.
Warning!G
Accident research shows that the safest
place for children in an automobile is in the
rear seat.
There is a possibility for a side impact air
bag related injury if occupants, especially
children, are not properly seated or re-
strained when next to a front side impact air
bag and/or rear side impact air bag* which
needs to deploy rapidly in a side impact in
order to do its job.
To help avoid the possibility of injury, please
follow these guidelines:
(1) Always sit as upright as possible,
properly use the seat belts, and for all
children 12 years old and under, use an
appropriately sized infant restraint, tod-
dler restraint, or booster seat recom-
mended for the size and weight of the
child.
(2) Always wear seat belts properly.iAir bags are designed to deploy only in cer-
tain frontal impacts (front air bags), and in side
impacts (front side impact air bags, rear side im-
pact* air bags, and window curtain air bags)
which exceed preset thresholds, and in certain
rollovers (window curtain air bags). Only during
these events will they provide their supplemental
protection.
The driver and passengers should always wear
their seat belts. Otherwise it is not possible for
air bags to provide their supplemental protec-
tion.
In case of other types of impacts and impacts be-
low air bag deployment thresholds, air bags will
not deploy. The driver and passenger will then be
protected to the extent possible by a properly
fastened seat belt. A properly fastened seat belt
is also needed to provide the best possible pro-
tection in a rollover.
We caution you not to rely on the presence of the
air bags in order to avoid wearing your seat belt.
It is important to your safety and that of your pas-
sengers that you replace deployed air bags and
repair any malfunctioning air bags to make sure
the vehicle will continue to provide supplemental
crash protection for occupants.

39 Safety and Security
Occupant safety
When you sell your vehicle we strongly
urge you to give notice to the subsequent
owner that it is equipped with an SRS by
alerting them to the applicable section in
the Operator’s Manual.
Front air bags
1Driver air bag
2Front passenger front air bag
The front air bags are designed to provide
increased protection for the driver and
front passenger against the risk of injuries
to the head and thorax.
Driver and front passenger front air bag are
deployed:
in the event of certain frontal impacts

if impact exceeds a preset deployment
threshold

if the system determines that airbag
deployment can offer additional pro-
tection to that provided by the seat belt

depending on whether the seat belt is
in use

independently of the front side impact
air bags, rear side impact air bags*
and/or the window curtain air bags.

For your protection and the protection
of others, when scrapping the air bag
unit or emergency tensioning device,
our safety instructions must be fol-
lowed. These instructions are available
from your authorized Mercedes-Benz
Center.

Given the considerable deployment
speed, required inflation volume, and
the textile structure of the air bags,
there is the possibility of abrasions or
other, potentially more serious injuries
resulting from air bag deployment.
Warning!G
Only use seat covers which have been
tested and approved by Mercedes-Benz for
your vehicle model. Using other seat covers
may interfere with or prevent the
deployment of the front side impact air bags
or the rear side impact air bags. Contact an
authorized Mercedes-Benz Center for avail-
ability.
iThe front air bags in this vehicle have been
designed to inflate in two stages. This allows the
air bag to have different rates of inflation that are
based on the rate of relevant vehicle decelera-
tion as assessed by the air bag control unit.
On the front passenger-side, the front air bag de-
ployment is additionally influenced by the pas-
senger’s weight category as identified by the
Occupant Classification System (OCS)
(
page 41).
The lighter the front passenger-side occupant,
the higher the vehicle deceleration rate required
for the second stage inflation of the air bag.

40 Safety and Security
Occupant safety
The front air bags will not deploy in im-
pacts which do not exceed the system’s
deployment thresholds. You will then be
protected by the fastened seat belts.
The front airbags are not deployed in the
event of a rollover unless the vehicle's rate
of longitudinal deceleration or acceleration
exceeds the preset deployment threshold
for the front air bags.
The front passenger front air bag2
(
page 39) will only be deployed if:

the system, based on OCS weight sen-
sor readings, senses that the front
passenger seat is occupied

the 5/indicator lamp in the
center console is not lit (
page 45)

the impact exceeds a preset deploy-
ment thresholdFront side impact air bags and rear side
impact air bags*
1Front side impact air bag
2Rear side impact air bag*
When deployed, the front side impact air
bags1 and/or the rear side impact air
bags*2 are designed to provide in-
creased protection for the thorax (but not
the head, neck and arms) of the occupants
on the side of the vehicle on which the im-
pact occurs.The front side impact air bags1 and the
rear side impact air bags*2 are
deployed:

on the impacted side of the vehicle

in impacts exceeding a preset deploy-
ment threshold

independently of the front air bags
The front passenger front side impact air
bag1 will not deploy if the OCS senses
that the front passenger seat is empty and
the front passenger seat belt is not fas-
tened (latch plate is not inserted into the
buckle). With an empty front passenger
seat and the seat belt fastened (latch plate
properly inserted into buckle) the front
passenger side impact air bag1 will
deploy regardless of the empty seat.
The front side impact air bags1 and the
rear side impact air bags*2 are not de-
ployed in impacts which do not exceed the
system’s deployment threshold.

41 Safety and Security
Occupant safety
Window curtain air bags
1Window curtain air bag
When deployed, the window curtain air
bags1 are designed to provide increased
protection for the head (but not the chest
or arms) of the occupants on the side of
the vehicle on which the impact occurs.
The window curtain air bags fill up the area
indicated by the arrows.The window curtain air bags are deployed:

on the impacted side of the vehicle

in impacts exceeding a preset deploy-
ment threshold

independently of the front air bags

regardless of whether the front-pas-
senger seat is occupied

in certain vehicle rollovers
The side window curtain air bags are not
deployed in impacts which do not exceed
the system’s deployment threshold.
Occupant Classification System
The Occupant Classification System (OCS)
automatically turns the front passenger
front air bag on or off based on the classi-
fied occupant weight category determined
by weight sensor readings from the front
passenger seat.
Occupants must sit properly belted in a
position that is as upright as possible with
their back against the seat backrest and
feet on the floor to be correctly classified.
If the occupant’s weight is transferred to
another object in the vehicle (e.g. by lean-
ing on armrests), the OCS may not be able
to properly approximate the occupant’s
weight category.
iThe system does not deactivate the front
passenger side impact air bag, the window cur-
tain air bag and the emergency tensioning de-
vice.

43 Safety and Security
Occupant safety
More information about air bag display
messages (
page 393).
When the OCS senses that the front passen-
ger seat occupant is classified as an adult or
someone larger than a small individual, the
5/indicator lamp will illuminate for
approximately 6 seconds when the engine is
started and then go out, indicating that the
front passenger front air bag is activated.
If the 5/indicator lamp is
illuminated, the front passenger front air
bag is deactivated and will not be deployed.
If the 5/indicator lamp is not
illuminated, the front passenger front air
bag is activated and will be deployed:

in the event of certain frontal impacts

if impact exceeds a preset deployment
threshold

independently of the front side impact
air bags and/or rear side impact air
bags*.
If the front passenger front air bag is
deployed, the rate of inflation will be
influenced by:

the rate of relevant vehicle deceleration
as assessed by the air bag control unit

front passenger’s weight category as
identified by the Occupant Classification
System (OCS).
Warning!G
According to accident statistics, children
are safer when properly restrained in the
rear seating positions than in the front seat-
ing position. Thus, we strongly recommend
that children be placed in the rear seats
whenever possible. Regardless of seating
position, children 12 years old and under
must be seated and properly secured in an
appropriate infant or child restraint recom-
mended for the size and weight of the child.
The infant or child restraint must be properly
secured with the vehicle’s seat belt, the seat
belt and top tether strap, or lower anchors
and top tether strap, fully in accordance
with the child seat manufacturer’s
instructions.
Children can be killed or seriously injured by
an inflating air bag. Note the following im-
portant information when circumstances re-
quire you to place a child in the front
passenger seat:

Your vehicle is equipped with air bag
technology designed to turn off the front
passenger front air bag in your vehicle
when the system senses the weight of a
typical 12-month-old child or less along
with the weight of a standard appropri-
ate child restraint on the front passen-
ger seat.

A child in a rear-facing child restraint on
the front passenger seat will be
seriously injured or even killed if the
front passenger front air bag inflates in
a collision which could occur under
some circumstances, even with the air
bag technology installed in your vehicle.
The only means to completely eliminate
this risk is to never place a child in a
rear-facing child restraint in the front
seat. We therefore strongly recommend
that you always place a child in a rear-
facing child restraint in the back seat.


48 Safety and Security
Occupant safety
Enhanced seat belt reminder system
When the engine is started, the seat belt
telltale< will always illuminate for
6 seconds to remind you and your passen-
gers to fasten your seat belts.
If the driver’s seat belt is not fastened
when the engine is started, an additional
warning chime will also sound for a maxi-
mum of 6 seconds or until the driver’ s
seat belt is fastened.
If after these 6 seconds the driver’s or the
front passenger’s seat belt (with the front
passenger seat occupied) is not fastened
with front doors closed,

the seat belt telltale< remains illu-
minated for as long as either the driv-
er’s or front passenger’s seat belt is not
fastened.

and if the vehicle speed once exceeds
15 mph (25 km/h), the seat belt
telltale< starts flashing and a
warning chime sounds with increasing
impacts which exceed preset deploy-
ment thresholds and in certain rollovers
(window curtain air bags and ETD).

Never wear the shoulder belt under your
arm, against your neck or off your shoul-
der. In a frontal crash, your body would
move too far forward. That would
increase the chance of head and neck
injuries. The seat belt would also apply
too much force to the ribs or abdomen,
which could severely injure internal
organs such as your liver or spleen.

Never wear seat belts over rigid or
breakable objects in or on your clothing,
such as eyeglasses, pens, keys, etc., as
these might cause injuries.

Position the lap belt as low as possible
on your hips and not across the abdo-
men. If the seat belt is positioned across
your abdomen, it could cause serious
injuries in a crash.

Never use a seat belt for more than one
person at time. Do not fasten a seat belt
around a person and another person or
other objects.

Seat belts should not be worn twisted.
In a crash, you wouldn’t have the full
width of the seat belt to distribute
impact forces. The twisted seat belt
against your body could cause injuries.

Pregnant women should also always use
a lap-shoulder belt. The lap belt portion
should be positioned as low as possible
on the hips to avoid any possible
pressure on the abdomen.

Never place your feet on the instrument
panel, dashboard or on the seat. Always
keep both feet on the floor in front of the
seat.

When using a seat belt to secure infant
restraint, toddler restraint, or booster
seat, always follow the child seat manu-
facturer’s instructions.


50 Safety and Security
Occupant safety
Active head restraints
The active head restraints are intended to
offer the driver and front passenger in-
creased protection from whiplash type in-
juries. In the event of a rear-end collision,
the active head restraints on the driver’s
and front passenger’s seats are designed
to move forward in the direction of travel,
providing the head with increased support
earlier on in the collision sequence. The ac-
tive head restraints move forward whether
the seat is occupied or not.If the active head restraints have been trig-
gered in an accident, the active head re-
straints must be reset. Otherwise, the
active head restraints cannot offer any ad-
ditional protection in the event of another
rear-end collision.
For information on resetting the activated
active head restraints, see “Resetting acti-
vated head restraints” (
page 427).
You cannot remove the active head re-
straint on the driver’s and front passen-
ger’s seats.
For removal contact an authorized
Mercedes-Benz Center.For information on head restraint adjust-
ment, see “Adjusting rear head restraints”
(
page 89).Warning!G
Do not attach any objects (e.g. hangers) to
the head restraint posts. Otherwise, the ac-
tive head restraints may not function prop-
erly or offer the degree of protection they
were designed for in the event of an acci-
dent.Warning!G
Only use seat or head restraint covers which
have been tested and approved by
Mercedes-Benz for your vehicle model.
Using other seat or head restraint covers
may interfere with or prevent the activation
of the active head restraints. Contact an
authorized Mercedes-Benz Center for avail-
ability.
Warning!G
For your protection, drive only with properly
positioned head restraints.
Adjust head restraint so that it is as close to
the head as possible and the center of the
head restraint supports the back of the head
at eye level. This will reduce the potential for
injury to the head and neck in the event of
an accident or similar situation.

99 Controls in detail
Mirrors
Folding exterior rear view mirrors in
and out automatically
When the corresponding function in the
control system is activated (
page 175):

The exterior rear view mirrors automat-
ically fold in as soon as the vehicle is
locked from the outside.

The exterior rear view mirrors automat-
ically fold out as soon as the vehicle is
unlocked and the driver’s or front pas-
senger door are subsequently opened.Resetting the automatic exterior rear
view mirror fold in function
You need to reset the automatic exterior
rear view mirror fold in function whenever
the battery was disconnected or dis-
charged.
Switch on the ignition.
Briefly press button1.Interior rear view mirror, antiglare
position
1Lever
Tilt the mirror to the antiglare position
by moving lever 1 towards the wind-
shield.
The interior rear view mirror is dimmed.
iThe mirrors do not fold out automatically if
they were previously folded in manually with
button1.
iIf you are driving at more than approximately
9 mph (15 km/h), you will not be able to fold the
exterior mirrors in.
iYou need to manually fold in the mirrors
once, so that the automatic fold in function will
work, see “Setting fold-in function* for exterior
rear view mirrors” (
page 175).

112 Controls in detail
Lighting
Switching on high beams
Combination switch
1High beam
2High beam flasher
High beam: Turn the exterior lamp
switch to positionB (
page 108).
Push the combination switch in the di-
rection of arrow1.
The high beam indicatorA in the in-
strument cluster comes on
(
page 26).
High beam flasher: Pull the combina-
tion switch briefly in the direction of
arrow2.
Headlamp cleaning system*
The headlamps are automatically cleaned
with a high-pressure water jet when, at the
same time,

the engine is running

the headlamps are switched on

the windshield wipers have wiped the
windshield with washer fluid for the
first time.
The headlamps are cleaned every tenth
time the windshield is washed with washer
fluid.
When you switch off the headlamps or the
ignition, the automatic function is reset
and will start counting the next time from
the beginning.
For information on filling up the washer
reservoir, see “Windshield washer system
and headlamp cleaning system*”
(
page 330).Corner-illuminating front fog lamps*
(With Bi-Xenon* headlamps only)
The corner-illuminating front fog lamps
improve illumination of the area in the
direction into which you are turning.
The corner-illuminating front fog lamps will
operate with the engine running and with:

the exterior lamp switch in
positionB or* (
page 108)
or

the daytime running lamp mode acti-
vated (
page 110).
iThe corner-illuminating front fog lamps will
only come on in low ambient lighting conditions.
iIf you are driving faster than 25 mph
(40 km/h) or have the front fog lamps switched
on, the corner-illuminating front fog lamps
function is not available.