2008 MERCEDES-BENZ S550 4MATIC sensor

451 Controls in detail
Driving systems
Front sensors
Rear sensorsWarning indicators
Visual signals indicate to the driver the rel-
ative distance between the sensors and an
obstacle.
The warning indicator for the front area is
in the instrument cluster. The warning indi-
cator for the rear area is on the roof liner in
the rear.
1Left side of the vehicle
2Right side of the vehicle
3Indicator
Each warning indicator is divided into five
yellow and two red distance segments for
either side of the vehicle.
If yellow indicators 3 under the segments
are lit, Park Assist is ready to measure.The position of the gear selector lever de-
termines which warning indicators will be
activated.
As your vehicle approaches an object, one
or more distance segments will illuminate,
depending on the distance. When the sev-
enth distance segment illuminates, you
have reached the minimum distance.
iDue to the sensors’ broad detection range,
it is possible that Park Assist also detects the fol-
lowing obstacles and issues a warning:

obstacles in the ground, e.g. sewer canal
covers, rails, bumps in the road or gutters

obstacles moving upward quickly, e.g. rolling
garage doors
Centerapprox. 40 in (100 cm)
Cornersapprox. 24 in (60 cm)
Centerapprox. 50 in (125 cm)
Cornersapprox. 24 in (60 cm)
!While parking, pay particular attention to ob-
jects over or underneath the sensors, e.g. flower
boxes, an elevated crossbar or a trailer tow
hitch. Park Assist does not detect such nearby
objects. You could otherwise damage the vehicle
or the objects.
Gear selector
lever positionWarning indicator
DFront area activated
RFront and rear area
activated
NWith the electronic
parking brake engaged:
neither activated.
With the electronic
parking brake released:
front and rear area acti-
vated.
PNeither activated

452 Controls in detail
Driving systems

Front area:
As soon as the first red segment lights
up, you will hear an intermittent warn-
ing tone for approximately two sec-
onds. Once the second red segment
lights up, you will hear a continuous
warning tone. You have reached the
minimum distance.

Rear area:
As soon as the first red segment lights
up, you will hear an intermittent warn-
ing tone for approximately two sec-
onds. Once the second red segment
lights up, you will hear a continuous
warning tone. You have reached the
minimum distance.Collision warning
Park Assist can detect obstacles from a
considerable distance. If you drive in re-
verse towards an obstacle, you will hear a
warning tone. You must then brake in or-
der to avoid a collision. The warning tone
for a collision will not sound when the vehi-
cle is at a standstill very close to the obsta-
cle. In this case, you will hear a
corresponding tone for the warning indica-
tor in the rear area.Switching Park Assist system on/off
The Park Assist system can be switched off
manually.
The Park Assist button with the indicator
lamp is located on the control panel on the
right-hand side of the instrument cluster.
1Park Assist button
2Indicator lamp
iDuring strong rainfall, the warning indicators
and warning tones may be triggered, for exam-
ple, by water splashing into the area of the sen-
sors.
iDuring strong rainfall, the collision warning
may be triggered, for example, by water splash-
ing into the area of the sensors.
iWhen the indicator lamp is on, the Park
Assist system is switched off.

453 Controls in detail
Driving systems
Switching off Park Assist system:
Press button 1.
Indicator lamp 2 comes on.
Switching on Park Assist system:
Press button 1 again.
Indicator lamp 2 goes out.
Dynamic Rear View Monitor*
The Dynamic Rear View Monitor is an elec-
tronic and visual parking aid. It shows you
the area behind the vehicle on the
COMAND display.
In addition, the Dynamic Rear View Moni-
tor contains guide lines to help you with re-
verse parking (back-in parking) and
parallel parking.
The area behind the vehicle is displayed as
a reverse-mirror image similar to the view
in a rear-view mirror.The Dynamic Rear View Monitor is in the
handle strip of the trunk lid.
1Dynamic Rear View Monitor
iThe Park Assist system is automatically
switched on when the ignition (
page 344) and
radar sensors are switched on (
page 282).
iThe Dynamic Rear View Monitor is also
called “Park Assist” in COMAND display.

524 Controls in detail
Useful features
Infrared reflecting windshield
Your vehicle is equipped with infrared re-
flecting glass, which reduces the amount
of radiated heat entering the vehicle interi-
or through the windows.
The infrared reflecting glass also prevents
the transmission of signals through the
glass by in-vehicle electronic devices
(e.g. electronic toll collection devices).
To allow the use of these devices in the ve-
hicle, transparent areas 1 and 3 are
placed in the windshield.
You can see them from certain angles
when ambient light condition permit.
Vehicles without Night View Assist*
1Transparent area (located left and right
to the cover of the rain light sensor)
2Cover of the rain light sensor
3Transparent area
Vehicles with Night View Assist*
1Transparent area (located left to the
cover of the rain light sensor)
2Cover of the rain light sensor
3Transparent area

536 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 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 Maintenance Booklet.Emission control
Certain systems of the engine and the
emission control system serve to keep the
toxic components of the exhaust gases
within permissible limits required by law.
These systems will function properly only
when maintained strictly according to fac-
tory specifications. Any adjustments on
the engine should, therefore, be carried
out only by qualified Mercedes-Benz Cen-
ter authorized technicians.
Engine adjustments should not be altered
in any way. The specified service proce-
dures must be carried out regularly accord-
ing to Mercedes-Benz servicing
requirements. For details please refer to
the Maintenance Booklet.
!To prevent damage to the catalytic convert-
ers, only use premium unleaded gasoline in this
vehicle.
Any noticeable irregularities in engine operation
should be repaired promptly. Otherwise, exces-
sive unburned fuel may reach the catalytic con-
verter, causing it to overheat and potentially
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.

561 Operation
Tires and wheels
Install the valve cap.
Repeat this procedure for each tire.
Checking tire inflation pressure elec-
tronically with the Advanced Tire Pres-
sure Monitoring System (Advanced
TPMS)*, (standard on U.S. vehicles)The TPMS only functions on wheels that
are equipped with the proper electronic
sensors. It monitors the tire inflation pres-
sure, as selected by the driver, in all four
tires. A warning is issued to alert you to a
decrease in pressure in one or more of the
tires.
Tire inflation pressure inquiries are made
using the multifunction display. The
present inflation pressures are displayed
only after a few minutes of travel time.
Switch on the ignition (page 344).
Press( or& to select the menu
“Service”.
Press$ or% to select “Tire
pressure”.
Press#.
iIf you have overfilled the tire, release tire in-
flation pressure by pushing the metal stem of the
valve with e.g. a tip of a pen. Then recheck the
tire inflation pressure with the tire gauge.
iThe Advanced Tire Pressure Monitoring
System (Advanced TPMS) is equipped with a
combination low tire pressure/TPMS malfunc-
tion telltale in the instrument cluster
(
page 608). Depending on how the telltale illu-
minates, it indicates a low tire inflation pressure
condition or a malfunction in the TPMS system it-
self:

If the telltale illuminates continuously, one
or more of your tires is significantly under-in-
flated. There is no malfunction in the TPMS.

USA only:
If the telltale flashes for 60 seconds and
then stays illuminated, the TPMS system it-
self is not operating properly.
iUSA only:
This device complies with Part 15 of the FCC
Rules. Operation is subject to the following two
conditions:
(1) This device may not cause harmful interfer-
ence, and
(2) this device must accept any interference re-
ceived, including interference that may
cause undesired operation.
Any unauthorized modification to this device
could void the user’s authority to operate the
equipment.
iCanada only:
This device complies with RSS-210 of Industry
Canada. Operation is subject to the following
two conditions:
(1) This device may not cause interference, and
(2) this device must accept any interference re-
ceived, including interference that may
cause undesired operation of the device.
Any unauthorized modification to this device
could void the user’s authority to operate the
equipment.iPossible differences between the readings
of a tire inflation pressure gauge of an air hose,
e.g. gas station equipment, and the vehicle’s
control system can occur. Usually the readings
issued by the control system are more precise.
iThe menu overview can be found on
(
page 266).


562 Operation
Tires and wheels
iWhen the message “Tire pressures dis-
played after driving a few minutes” appears in
the display, the individual inflation pressure val-
ues are matched with the tires. The individual
values are displayed after a few minutes driving.
Warning!G
It is the driver’s responsibility to calibrate
the TPMS on the recommended cold infla-
tion pressure. Underinflated tires affect the
ability to steer or brake the vehicle. You
might lose control over the vehicle.
iWith a spare wheel without wheel sensor
mounted, the system may still indicate the tire
inflation pressure of the removed wheel for some
minutes. If this happens, keep in mind that the
indicated value where the spare wheel is mount-
ed does not reflect the actual spare tire inflation
pressure.
Warning!G
The TPMS does not indicate a warning for
wrongly selected inflation pressures. Always
adjust tire inflation pressure according to
the Tire and Loading Information placard on
the driver’s door B-pillar or, if available, the
supplemental tire pressure information on
the inside of the fuel filler flap.
The TPMS is not able to issue a warning due
to a sudden dramatic loss of pressure (e.g.
tire blowout caused by a foreign object). In
this case bring the vehicle to a halt by care-
fully applying the brakes and avoiding
abrupt steering maneuvers.
Warning!G
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
vehicle Tire and Loading Information placard
or the tire inflation pressure label. If your ve-
hicle has tires of a different size than the
size indicated on the vehicle Tire and Load-
ing Information placard or the tire inflation
pressure label, you should determine the
proper tire inflation pressure for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitor-
ing system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires is significantly underinflated. Accord-
ingly, when the low tire pressure telltale illu-
minates, you should stop and check your
tires as soon as possible, and inflate then to
the proper pressure. Driving on a significant-
ly underinflated tire causes the tire to over-
heat and can lead to tire failure.


564 Operation
Tires and wheels
Switch on the ignition (page 344).
Press( or& to select the menu
“Service”.
Press$ or% to select “Tire
pressure”.
Press#.
You will see

the current inflation pressures for
each tire
or

the message
“Tire pressures
displayed after driving
a few minutes”
appear in the multifunction display.
Press%.
The message
“Use current pressure
values as new
reference values
To confirm press "OK"”
appears in the multifunction display.
Press#.
The message
“Tire pressure monitor
restarted”
appears in the multifunction display.
After a few minutes driving, the current
tire inflation pressure values are ac-
cepted as reference values and then
monitored.
If you wish to cancel activation:
PressL.
or
Press$ to exit menu screen.
iReactivate the TPMS after adjusting the tire
inflation pressure to the inflation pressure rec-
ommended for the vehicle operating condition.
Tire inflation pressure should only be adjusted
on cold tires. Observe the recommended tire in-
flation pressure on the Tire and Loading Informa-
tion placard on the driver’s door B-pillar
(
page 553). Some vehicles may have supple-
mental tire inflation pressure information for
driving at high speeds (
page 559) or for vehi-
cle loads less than the maximum loaded vehicle
condition. If such information is provided, it can
be found on the inside of the fuel filler flap
(
page 538).
iAfter wheel rotation or sensor replacement,
the vehicle must be parked for 20 minutes be-
fore attempting to reactivate the TPMS.
iThe menu overview can be found on
(
page 266).iWhen the wheel positions are changed on
the vehicle, it is possible that the air pressure is
temporarily displayed for the wrong position.
This will be corrected after driving for several
minutes, and the air pressure will be shown for
the correct position.