overheating MERCEDES-BENZ S550 4MATIC 2008 W221 Owner's Manual

162 Control systems
COMAND navigation (introduction)
Clean DVD.
See the “Notes about handling
DVDs” section (
page 159).
Restart update.

Overheating due to excessive tempera-
tures in the vehicle interior
Wait until vehicle interior has
cooled down.
Restart update.

The storage medium (hard disk) inte-
grated in COMAND is defective.
Consult an authorized
Mercedes-Benz Center.Map software is not compatible with
the navigation system
You will see a message that the update is
not possible.
Confirming message: Press n.
COMAND ejects the DVD.
Take DVD out of slot.
Load a DVD which is compatible with
the vehicle’s navigation system. Map software is not compatible with
the current system software
You will see a message that the system
software and the map software are not
compatible.
Confirming message: Press n.
COMAND ejects the DVD.
Take DVD out of slot.
Have the system software updated at
an authorized Mercedes-Benz Center.
iThe map software cannot be updated until
the system software has been updated.

528 Operation
Driving instructions
Brakes
To help prevent brake disk corrosion after
driving on wet road surfaces (particularly
salted roads), it is advisable to brake the
vehicle with considerable force prior to
parking. The heat generated serves to dry
the brakes.
If your brake system is normally only sub-
jected to moderate loads, you should occa-
sionally test the effectiveness of the
brakes by applying above-normal braking
pressure at higher speeds. This will also
enhance the grip of the brake pads.Refer to the description of the Brake Assist
System (BAS or BAS Plus*) (
page 68).
Brake pad wear or a leak in the system may
be the reason for low brake fluid level in
the reservoir.
The brake fluid level in the reservoir may
be too low if the red brake warning lamp in
the instrument cluster comes on while the
engine is running and an acoustic warning
sounds (
page 601). Observe additional
messages in the multifunction display that
may appear (
page 612).
Have the brake system inspected
immediately. Contact an authorized
Mercedes-Benz Center.
Warning!G
After driving in heavy rain for some time
without applying the brakes or through wa-
ter deep enough to wet brake components,
the first braking action may be somewhat
reduced and increased pedal pressure may
be necessary to obtain expected braking
effect. Maintain a safe distance from
vehicles in front.
Resting your foot on the brake pedal will
cause excessive and premature wear of the
brake pads.
It can also result in the brakes overheating,
thereby significantly reducing their effec-
tiveness. It may not be possible to stop the
vehicle in sufficient time to avoid an
accident.
!Because the ESP® operates automatically,
the engine and ignition must be shut off
(SmartKey in starter switch position0 or1 or
KEYLESS-GO start/stop button* in position0
or1) when

the electronic parking brake is being tested
on a brake test dynamometer

the vehicle is being towed with the
front/rear axle raised
Active braking action through the ESP
® may oth-
erwise seriously damage the brake system.
Warning!G
Make sure not to endanger any other road
users when carrying out these braking ma-
neuvers.

529 Operation
Driving instructions
All checks and service work on the brake
system should be carried out by qualified
technicians only. Contact an authorized
Mercedes-Benz Center.
Only install brake pads and brake fluid
recommended by Mercedes-Benz.After hard braking, it is advisable to drive
on for some time, rather than immediately
park, so that the air stream can cool down
the brakes faster.
High-performance brake system
(S 63 AMG and S 65 AMG only)
The high-performance brake system is de-
signed to operate under the extremely high
operating demands required to accommo-
date the performance capabilities of the
vehicle. The brakes may produce a squeak-
ing-type noise depending on the

vehicle speed

brake force applied

ambient conditions, e.g. temperature
and humidity
As with any brake system, the wear of indi-
vidual brake system components such as
brake pads or disks strongly depends on
your driving style and the conditions under which you operate the vehicle. Thus, a driv-
ing style calling for high demand braking
will cause your vehicle’s brakes to wear
more quickly.
Warning!G
If other than recommended brake pads are
installed, or other than recommended brake
fluid is used, the braking properties of the
vehicle can be degraded to an extent that
safe braking is substantially impaired. This
could result in an accident.
!When driving down long and steep grades,
relieve the load on the brakes by shifting into a
lower gear to use the engine’s braking power.
This helps prevent overheating of the brakes and
reduces brake pad wear.
When using the engine’s braking power, a drive
wheel may not spin for an extended period of
time, e.g. on slippery road surfaces.
This may cause serious damage to the drivetrain
which is not covered by the Mercedes-Benz Lim-
ited Warranty.
Warning!G
New vehicle brake pads and discs, and
replacement brake pads and discs may take
several hundred miles of driving until they
provide optimum braking efficiency. Until
that time, you may need to use increased
brake pedal pressure while braking. Please
be aware of this and adjust your driving and
braking accordingly during this break-in
period.
Excessive high demand braking will cause
correspondingly high brake wear. Please be
attentive to the brake warning lamp in the
instrument cluster and brake condition mes-
sages in the multifunction display. Especial-
ly for high performance driving, it is
important to maintain and have the brake
system checked regularly.

641 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Currently unavailable
See Oper. ManualESP® and PRE-SAFE® are temporarily un-
available. It is possible that the self-diag-
nostics have not yet completed.
In addition, the yellow ESP
® warning
lampv comes on.
The brake system functions normally.
BAS Plus* and PRE-SAFE
® Brake* are also
not available.
Synchronize the ESP®:
Drive a short distance with gentle turns at a
speed above 12 mph (20 km/h).
The message disappears when ESP
® is again
available.
Currently unavailable
See Oper. ManualESP® and PRE-SAFE® are switched off due
to undervoltage. It is possible that the bat-
tery is not charged.
The brake system functions normally.
BAS Plus* and PRE-SAFE
® Brake* are also
not available.
Continue driving with added caution.
Have the system checked at an authorized
Mercedes-Benz Center as soon as possible.
Failure to follow these instructions increases the
risk of an accident.
Currently unavailable
See Oper. ManualIf the yellow ESP® warning lampv flash-
es while driving and this message appears,
the electronic traction system has switched
off to prevent overheating of the drive
wheel brakes.
BAS Plus* and PRE-SAFE
® Brake* are also
not available.
As soon as the brakes have cooled off, the elec-
tronic traction system switches on again.
The message in the multifunction display disap-
pears and the ESP
® warning lampv goes
out.