Page 89 of 441

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.
Page 263 of 441

262 Operation
Driving instructions
Power assistanceBrakes
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
subject to moderate loads, you should
occasionally 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.
Warning!G
With the engine not running, there is no
power assistance for the brake and steering
systems. In this case, it is important to keep
in mind that a considerably higher degree of
effort is necessary to brake and steer the
vehicle.
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 ef-
fect. 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 acci-
dent.
!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 oth-
erwise seriously damage the brake system.
For information on vehicles with 4MATIC, see
“Four wheel electronic traction system (4MATIC)
with the ESP
® ” (page 88).
Page 264 of 441

263 Operation
Driving instructions
Refer to the description of the Brake Assist
System (BAS) (
page 84).
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 brake warning lamp in the
instrument cluster comes on and an
acoustic warning sounds although the
parking brake is released (
page 324).
Observe additional messages in the multi-
function display that may appear
(
page 344).
Have the brake system inspected
immediately. Contact an authorized
Mercedes-Benz Center.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 will cool down
the brakes faster.
Driving off
Apply the brakes to test them briefly after
driving off. Perform this procedure only
when the road is clear of other traffic.
Warm up the engine smoothly. Do not
place full load on the engine until the
operating temperature has been reached.
Warning!G
Make sure not to endanger any other road
users when carrying out these braking ma-
neuvers.
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 starting off on a slippery surface, do
not allow a drive wheel to spin for an extended
period with the ESP
® switched off. Doing so may
cause serious damage to the drivetrain which is
not covered by the Mercedes-Benz Limited
Warranty.
!Simultaneously depressing the accelerator
pedal and applying the brake reduces engine
performance and causes premature brake and
drivetrain wear.