2004 MERCEDES-BENZ E320 overheating

81 Safety and Security
Driving safety systems
The SBC brake servo assistance switches
off automatically

approximately two minutes after you
turned the SmartKey in the starter
switch to position0 or removed the
SmartKey


approximately two minutes after you
pressed the KEYLESS-GO* start/stop
button to turn off the engine or power
supply and opened the driver’s door
(with driver’s door open, the starter
switch is set to position 0, same as
SmartKey removed from starter
switch)


approximately 20 seconds after you
locked the vehicle from outside
Note on driving with the SBC


Following extended periods of only mi-
nor loads to your brake system, you
should occasionally apply the brakes
when traveling at high speeds. This im-
proves 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 in-
stalled on your vehicle. Brake pads not
approved by Mercedes-Benz may im-
pair the safety of your vehicle.
Warning!
G
Have brake pad replacement and other work
on the SBC brake system carried out by
qualified technicians only. Contact your
Mercedes-Benz Center for further informa-
tion. The SBC brake system must be deacti-
vated prior to working on the system. High
pressure is intermittently built up in the sys-
tem as part of its automatic self-test. In ad-
dition, the system is automatically activated
when the vehicle is unlocked by SmartKey,
when the driver or passenger door is
opened, when the starter switch is turned to
position
1, when the brake pedal is de-
pressed or when the parking brake is re-
leased. Failure to deactivate the system
prior to maintenance will cause brake pis-
tons to extend and brake fluid to leak, which
may result in injuries (contusions and acid
burns). Extended brake pistons may also
cause injury.
Warning!
G
Be very careful not to endanger other road
users when you apply the brakes.

268 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 sys-
tem operation and switch it into its emer-
gency operation mode. In such a case, the
red brake warning lamp (
page 312) and
warning messages in the instrument cluster
(
page 318) come on while driving. To
brake, the driver must then apply signifi-
cantly greater brake pedal pressure and de-
press 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. Stop-
ping distance is increased! If there is a mal-
function in the SBC brake system, we
recommend that the vehicle be transported
with all wheels off the ground using flatbed
or appropriate 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 381). For more information see
SBC brake system (
page 79).
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 ve-
hicle.
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.

269 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-
j e c t e d t o m o d e r a t e l o a d s , y o u s h o u l d o c c a -
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. If the parking brake is released and the
brake warning lamp in the instrument clus-
ter stays on, there is a malfunction in the
SBC brake system (
page 79) 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 your
authorized Mercedes-Benz Center.
All checks and service work on the brake
system should be carried out by qualified
technicians only. Contact your authorized
Mercedes-Benz Center.
Only install brake pads and brake fluid rec-
ommended by Mercedes-Benz.
After hard braking, it is advisable to drive
on for some time, rather than immediately
parking, so that the air stream will cool
down the brakes faster.
!Be very careful not to endanger other
road users when you apply the brakes.
Refer to the description of the Brake
Assist System (BAS) (
page 76).
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 326).!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 re-
duces brake pad wear.

314 Practical hintsWhat to do if …Problem
Possible cause
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 ra-
diator fan may be broken.

Immediately add coolant to prevent
engine from overheating
(page 285).

Have the cooling system checked.

If the coolant temperature is below
257 °F (125 °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
257 °F (125 °C).

Stop as soon as possible and allow
the engine and coolant to cool down.
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.