Page 93 of 498

92 Safety and SecurityDriving safety systemsNote on driving with the
electro-hydraulic brake system
Following extended periods of only
minor loads to your brake system, you
should occasionally apply the brakes
when traveling at high speeds. This
improves the grip of the brake pads.
After driving on wet or snow-covered
roads, you should apply your brakes
firmly before parking your vehicle. This
produces heat which serves to dry the
brake disks and help prevent corro-
sion.
On long and steep grades, shift to a
lower gear (gear range1, 2, or 3) to
prevent the brakes from overheating
and to reduce brake wear.
After hard braking, it is advisable to
drive on for some time so that the air
stream will cool down the brakes fast-
er.
Only Mercedes-Benz approved compo-
nents (e.g. brake pads) should be
installed on your vehicle. Brake pads
not approved by Mercedes-Benz may
impair the safety of your vehicle.
Warning!
G
Be very careful not to endanger other road
users when you apply the brakes.
Page 281 of 498

280 OperationDriving instructionsPower assistance
Brakes
Warning!
G
The brake system requires electrical energy
for operation.
A malfunction in the vehicle’s power supply
or electrical system may impair brake
system operation and switch it into its emer-
gency operation mode. In such a case, the
red brake warning lamp (
page 354) and
warning messages in the instrument cluster
(
page 363) come on while driving. To
brake, the driver must then apply signifi-
cantly greater brake pedal pressure and
depress the pedal much further to obtain
the expected braking effect. If necessary,
apply full pressure to the brake pedal.
Brakes may only be applied to the front
wheels. Stopping distance is increased!
If there is a malfunction in the
electro-hydraulic brake system, we recom-
mend that the vehicle be transported with
all wheels off the ground using flatbed or ap-
propriate wheel lift/dolly equipment. A tow
bar must be used if circumstances do not
permit the use of the recommended towing
methods and the vehicle requires towing
with all four wheels on the ground. Towing
the vehicle with all four wheels on the
ground is only permissible for distances up
to 30 miles (50 km) and at a speed not to
exceed 30 mph (50 km/h). For more infor-
mation, refer to “Towing the vehicle”
(page 437). For more information, see
“Electro-hydraulic brake system”
(page 89).
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.
Page 282 of 498

281 Operation
Driving instructions
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) (
page 86).If the parking brake is released and the
brake warning lamp in the instrument clus-
ter stays on, there is a malfunction in the
electro-hydraulic brake system
(
page 89) or the brake fluid level in the
reservoir is too low.
Brake pad wear or a leak in the system may
be the reason for low brake fluid in the res-
ervoir.
Have the brake system inspected by quali-
fied technicians 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.
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.
Be certain to read and observe the warning
notices on brake pad replacement
(page 374).!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 pre-
vent overheating of the brakes and
reduces brake pad wear.
Page 358 of 498

357 Practical hints
What to do if …
Problem
Possible cause/consequence
Suggested solution
D
The red coolant warning lamp
comes on when the engine is
running.
There is insufficient coolant in the reservoir.
If this warning lamp comes on frequently,
there is a leak in the cooling system.
If the coolant level is correct, the electric
radiator fan may be broken.
Immediately add coolant to prevent
engine from overheating
(page 297).
Have the cooling system checked.
If the coolant temperature is below
266°F (130°C), you can continue
driving to the nearest authorized
Mercedes-Benz Center.
Avoid high engine loads (e.g. driving
uphill) and stop-and-go driving.
D
The red coolant warning lamp
comes on while driving and you
hear a warning sound.
The coolant temperature has exceeded
266°F (130°C).
Stop as soon as possible and allow
the engine and coolant to cool down.
l
The red distance warning lamp
comes on while driving.
You are too close to the vehicle in front of you
to maintain selected speed.
Apply the brakes immediately to in-
crease the following distance.
Warning!
G
Driving when your engine is badly overheat-
ed can cause some fluids which may have
leaked into the engine compartment to
catch fire. You could be seriously burned.
Steam from an overheated engine can cause
serious burns and can occur just by opening
the engine hood. Stay away from the engine
if you see or hear steam coming from it.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until the
engine has cooled down.