2007 MERCEDES-BENZ C230 ECU

81 Safety and Security
Panic alarm*
Panic alarm*
1Âbutton
Activating
Press and hold button for at least
1 second.
An audible alarm and flashing exterior
lamps will operate briefly.
Deactivating
Press button again.
or
Insert SmartKey in starter switch.iCanada only:
Only vehicles equipped with an anti-theft alarm
system* have SmartKeys with integrated panic
button1.
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.

82 Safety and Security
Driving safety systems
In this section you will find information on
the following driving safety systems:

ABS (Antilock Brake System)

BAS (Brake Assist System)

ESP® (Electronic Stability Program)

4MATIC (Four Wheel Electronic
Traction System)
ABS
The Antilock Brake System (ABS) regulates
the brake pressure so that the wheels do
not lock during braking. This allows you to
maintain the ability to steer your vehicle.
The ABS is functional above a speed of
approximately 5 mph (8 km/h) indepen-
dent of road surface conditions.
On slippery road surfaces, the ABS will
respond even to light brake pressure.
The- indicator lamp in the instrument
cluster (
page 24) comes on when you
switch on the ignition. It goes out when the
engine is running.
Warning!G
The following factors increase the risk of
accidents:

Excessive speed, especially in turns

Wet and slippery road surfaces

Following another vehicle too closely
The ABS, BAS, ESP
®, and 4MATIC (if so
equipped) cannot reduce this risk.
Always adjust your driving style to the
prevailing road and weather conditions.
iIn winter operation, the maximum
effectiveness of the ABS, ESP®, and 4MATIC (if
so equipped) is only achieved with winter tires
(
page 308), or snow chains as required.
Warning!G
Do not pump the brake pedal. Use firm,
steady brake pedal pressure instead. Pump-
ing the brake pedal defeats the purpose of
the ABS and significantly reduces braking
effectiveness.

83 Safety and Security
Driving safety systems
Braking
At the instant one of the wheels is about to
lock up, a slight pulsation can be felt in the
brake pedal, indicating that the ABS is in
the regulating mode.
Keep firm and steady pressure on the
brake pedal while experiencing the
pulsation.
Continuous steady brake pedal pressure
yields the advantages provided by the ABS,
namely braking power and ability to steer
the vehicle.
The pulsating brake pedal can be an
indication of hazardous road conditions
and functions as a reminder to take extra
care while driving.Emergency brake maneuver
Keep continuous full pressure on the
brake pedal.
For more information, see the “Practical
hints” section (
page 322).
Warning!G
When the ABS is malfunctioning, the BAS
and the ESP® are also switched off. The ba-
sic driving and braking functions are still
available
When the ABS is malfunctioning, the wheels
may lock during hard braking, reducing
steering capability and extending the brak-
ing distance.
Warning!G
The ABS cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase braking or steering efficiency
beyond that afforded by the condition of the
vehicle brakes and tires or the traction avail-
able on the road surface. The ABS cannot
prevent accidents, including those resulting
from excessive speed in turns, following an-
other vehicle too closely, or hydroplaning.
Only a safe, attentive, and skillful driver can
prevent accidents. The capabilities of an
ABS equipped vehicle must never be exploit-
ed in a reckless or dangerous manner which
could jeopardize the user’s safety or the
safety of others.

84 Safety and Security
Driving safety systems
BAS
The Brake Assist System (BAS) operates in
emergency situations. If you apply the
brakes very quickly, the BAS automatically
provides full brake boost, thereby poten-
tially reducing the braking distance.
Apply continuous full braking pressure
until the emergency braking situation is
over.
The ABS will prevent the wheels from
locking.
When you release the brake pedal, the
brakes function again as normal. The BAS
is then deactivated.
Warning!G
If the BAS is malfunctioning, the brake sys-
tem is still functioning normally, but without
the additional brake boost available that
BAS would normally provide in an emergen-
cy braking maneuver. Therefore, the braking
distance may increase.
Warning!G
The BAS cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase braking efficiency beyond that
afforded by the condition of the vehicle
brakes and tires or the traction. The BAS
cannot prevent accidents, including those
resulting from excessive speed in turns,
following another vehicle too closely, or
hydroplaning. Only a safe, attentive, and
skillful driver can prevent accidents. The
capabilities of a BAS equipped vehicle must
never be exploited in a reckless or danger-
ous manner which could jeopardize the
user’s safety or the safety of others.

85 Safety and Security
Driving safety systems
ESP®
The Electronic Stability Program (ESP®) is
operational as soon as the engine is run-
ning and monitors the vehicle’s traction
(force of adhesive friction between the
tires and the road surface) and handling.
The ESP
® recognizes when a wheel is
spinning or if the vehicle starts to skid. By
applying the brakes to the appropriate
wheel and by limiting the engine output,
the ESP
® works to stabilize the vehicle.
The ESP® is especially useful while driving
off and on wet or slippery road surfaces.
The ESP
® also stabilizes the vehicle during
braking and steering maneuvers.
The ESP
® warning lampv in the
instrument cluster flashes when the ESP®
is engaged.
The ESP
® warning lampv in the
instrument cluster comes on when you
switch on the ignition. It goes out when the
engine is running.
Warning!G
Never switch off the ESP® when you see the
ESP® warning lampv flashing in the
instrument cluster. In this case, proceed as
follows:

While driving off, apply as little throttle
as possible.

While driving, ease up on the accelera-
tor.

Adapt your speed and driving style to
the prevailing road conditions.
Failure to observe these guidelines could
cause the vehicle to skid.
The ESP
® cannot prevent accidents result-
ing from excessive speed.
Warning!G
The ESP® cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase the traction afforded by the exist-
ing road and tire conditions. The ESP
®
cannot prevent accidents, including those
resulting from excessive speed in turns or
hydroplaning. Only a safe, attentive, and
skillful driver can prevent accidents. The
capabilities of an ESP
® equipped vehicle
must never be exploited in a reckless or dan-
gerous manner which could jeopardize the
user’s safety or the safety of others.

86 Safety and Security
Driving safety systems
For more information, see the “Practical
hints” section (
page 327) and
(
page 335).Electronic traction system
The electronic traction system is a
component of ESP
®.
The electronic traction system improves
the vehicle’s ability to utilize available
traction, especially under slippery road
conditions by applying the brakes to a
spinning wheel.
When you switch off the ESP
®, the
electronic traction system is still enabled.Switching off the ESP
®
To improve the vehicle’s traction, turn off
the ESP® in driving situations where it
would be advantageous to have the drive
wheels spin and thus cut into surfaces for
better grip such as:

when driving with snow chains

in deep snow

in sand or gravel
!Vehicles without 4MATIC:
Because the ESP® operates automatically, the
engine must be turned off (SmartKey in starter
switch position0 or1) when

the parking brake is being tested on a brake
test dynamometer

the vehicle is being towed with the front axle
raised
Active braking action through the ESP
® may
otherwise seriously damage the brake system.
For information on vehicles with 4MATIC, see
“Four wheel electronic traction system (4MATIC)
with the ESP
® ” (page 88).
iThe ESP® will only function properly if you
use wheels of the recommended tire size
(
page 403).
Warning!G
If you are driving too fast, the electronic
traction system cannot reduce the risk of an
accident.
The electronic traction system cannot pre-
vent the natural laws of physics from acting
on the vehicle.
Warning!G
The ESP® should not be switched off during
normal driving other than in the circum-
stances described below. Disabling of the
system will reduce vehicle stability in stan-
dard driving maneuvers.
Do not switch off the ESP
® when a
Minispare wheel is mounted.
!Switch on the ESP® immediately if the
aforementioned circumstances do not apply
anymore.

87 Safety and Security
Driving safety systems
When you switch off the ESP®

the ESP® does not stabilize the vehicle

the engine output is not limited, which
allows the drive wheels to spin and
thus cut into surfaces for better grip

the traction control will still apply the
brakes to a spinning wheel

the ESP® continues to operate when
you are braking

you cannot activate the cruise control

the cruise control switches off if
currently activatedThe ESP
® switch is located on the center
console.
1ESP
® switch
With the engine running, press ESP®
switch1 until the ESP® warning
lampv in the instrument cluster
comes on.
The ESP
® is switched off.
Switching on the ESP®
Press ESP® switch1 until the ESP®
warning lampv in the instrument
cluster goes out.
You are now again in normal driving
mode with ESP
® switched on.
iWhen the ESP® is switched off and one or
more drive wheels are spinning, the ESP® warn-
ing lampv in the instrument cluster flashes.
However, the ESP
® will then not stabilize the ve-
hicle.
Warning!G
When the ESP® warning lampv is
illuminated continuously, the ESP® is
switched off or is not operational due to a
malfunction. Vehicle stability in standard
driving maneuvers reduces.
Adapt your speed and driving to the prevail-
ing road conditions and to the non-operating
status of the ESP
®.
!Avoid spinning of a drive wheel for an
extended period with the ESP® switched off. This
may cause serious damage to the drivetrain
which is not covered by the Mercedes-Benz
Limited Warranty.

88 Safety and Security
Driving safety systems
Four wheel electronic traction system
(4MATIC) with the ESP®
Models with all-wheel-drive only.
The 4MATIC improves vehicle’s ability to
use available traction, e.g. during winter
operation in mountains under snowy
conditions, by applying power to all four
wheels.
Warning!G
If you see the ESP® warning lampv
flashing in the instrument cluster, proceed
as follows:

While driving off, apply as little throttle
as possible

While driving, ease up on the accelera-
tor

Adapt your speed and driving style to
the prevailing road conditions
Failure to observe these guidelines could
cause the vehicle to skid.
The ESP
® cannot prevent accidents result-
ing from excessive speed.
!Do not tow with one axle raised.
Otherwise the transfer case can be damaged,
which is not covered by the Mercedes-Benz
Limited Warranty.
!Performance testing must only be conduct-
ed on a two-axle dynamometer.
Otherwise the transfer case can be damaged,
which is not covered by the Mercedes-Benz
Limited Warranty.
!Because the ESP® operates automatically,
the engine must be shut off (SmartKey in starter
switch position0 or1) when the parking brake is
being tested on a brake test dynamometer.
Active braking action through the ESP
® may
otherwise seriously damage the front or rear axle
brake system.
Operational tests with the engine running can
only be conducted on a two-axle dynamometer.
iAt highly demanding operating conditions,
the electronic traction system may temporarily
switch off to prevent overheating of the drive
wheel brakes. The message
unavailable
See Operator’s Manual
will then appear in
the multifunction display while the ESP® warning
lampv is flashing. The ESP® is still function-
ing normally.