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380 Practical hints
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2 Brake WearThe brake pads have reached their
wear limit.Have the brake pads replaced as soon as pos-
sible.
Warning!G
Have brake pad replacement and other work
on the electro-hydraulic brake system
carried out by qualified technicians only.
Contact an authorized Mercedes-Benz
Center for further information.
The electro-hydraulic brake system must be
deactivated prior to working on the system.
High pressure is intermittently built up in the
system as part of its automatic self-test.
In addition, the system is automatically
activated when the vehicle is unlocked by
remote control, when the driver or passen-
ger door is opened, when the SmartKey in
the starter switch is turned to position1 or
the KEYLESS-GO* start/stop button is
pressed once, when the brake pedal
is depressed or when the parking brake is
released. 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.!Brake pad thickness must be visually
checked by a qualified technician at the intervals
specified in the Maintenance Booklet.
Page 382 of 489
381 Practical hints
What to do if …
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USA only:
;
Canada only:
3
Check
Brake Fluid LevelThere is insufficient brake fluid in
the reservoir.Risk of accident!
Stop the vehicle in a safe location or as soon
as it is safe to do so.
Do not drive any further.
Contact an authorized Mercedes-Benz
Center.
Do not add brake fluid! This will not solve the
problem.
Warning!G
Driving with the message Check Brake
Fluid Level
displayed can result in an
accident. Have your brake system checked
immediately. Do not add brake fluid before
checking the brake system. Overfilling the
brake fluid reservoir can result in spilling
brake fluid on hot engine parts and the
brake fluid catching fire. You could be
seriously burned.
!If you find that the brake fluid in the brake
fluid reservoir has fallen to the minimum mark or
below, have the brake system checked for brake
pad thickness and leaks.
Page 383 of 489
382 Practical hints
What to do if …
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USA only:
;
Canada only:
3
Brake
Service
RequiredThere are malfunctions, but the
electro-hydraulic brake system is
operating normally.Contact an authorized Mercedes-Benz Center
as soon as possible.
Brakes Overheated
Drive on, but with
even greater care
.
The brake system is overheated due
to an excessive load on the brakes.Relieve the load on the brake system:
Drive more smoothly and think ahead to
avoid unnecessary braking.
When driving down steep grades, shift into
a lower gear to use the engine’s braking
power (
page 179).
Cautiously continue driving so that the air
stream will cool down the brakes.
USA only:
;
Canada only:
!
Release
Parking BrakeYou are driving with the parking
brake set.Release the parking brake (page 63).
Page 384 of 489
383 Practical hints
What to do if …
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•Coolant
Stop car,
switch engine off.
The coolant is too hot.
Among other possible causes, the
poly-V-belt could be broken.Stop the vehicle in a safe location or as soon
as it is safe to do so.
Turn off the engine.
Check the poly-V-belt.
If it is broken:
Do not continue to drive. Otherwise, the
engine will overheat due to an inoperative
water pump which may result in damage to
the engine. Contact an authorized
Mercedes-Benz Center.
If it is intact:
Wait for the message to disappear before
restarting the engine.
Doing otherwise could result in serious engine
damage that is not covered by the
Mercedes-Benz Limited Warranty.
(Continued on next page)
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384 Practical hints
What to do if …
During severe operating conditions, e.g.
stop-and-go traffic, the coolant tempera-
ture may rise close to 248°F (120°C).
Left displayRight displayPossible cause/consequencePossible solution
Observe the coolant temperature gauge in the
instrument cluster (
page 27).
If the temperature rises again:
Contact an authorized Mercedes-Benz
Center immediately.
Warning!G
Driving when your engine is overheated 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.
!The engine should not be operated with the
coolant temperature above 248°F (120°C). Do-
ing so may cause serious engine damage which
is not covered by the Mercedes-Benz Limited
Warranty.
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385 Practical hints
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BTop Up
Coolant
See Oper. ManualThe coolant level is too low.Add coolant (page 288).
Comply with all warnings while doing so.
If you have to add coolant frequently, have the
cooling system checked by an authorized
Mercedes-Benz Center.
•The cooling fan for the coolant is
malfunctioning.Observe the coolant temperature gauge in the
instrument cluster (
page 27).
If the coolant temperature is below 120°C,
you may continue driving to the nearest
specialist workshop.
Avoid placing heavy loads on the engine
(e.g. by driving uphill) as well as stop-and-go
traffic.
Have the fan replaced as soon as possible.
Warning!G
Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts. You could be seriously burned.
!Do not ignore the low engine coolant level
warning. Extended driving with this message and
symbol displayed may cause serious engine
damage not covered by the
Mercedes-Benz Limited Warranty. Do not drive
without sufficient amount of coolant in the cool-
ing system. The engine will overheat, causing
major engine damage.
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386 Practical hints
What to do if …
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2You are attempting to drive with
one or more doors open.Close the doors.
Vehicles with KEYLESS-GO*:
You are pressing the lock button on
the door handle and at least one
door is open.
±Service
RequiredCertain electronic systems are
unable to relay information to the
control system. The following
systems may have failed:
Coolant temperature gauge
Tachometer
Have the electronic systems checked by an
authorized Mercedes-Benz Center
(
page 346).
_ Entry Position
Do Not DriveThe steering wheel has not yet
moved into its stored driving posi-
tion.Wait until the steering wheel has moved to its
driving position.
The message disappears.
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387 Practical hints
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When the message Add 1 qt engine oil
at next refueling
(Canada: 1 liter)
appears while the engine is running and at
operating temperature, the engine oil level
has dropped to approximately the
minimum level.
When this occurs, the warning is at first
intermittent and then remains on if the oil
level drops further.Visually check for oil leaks. If there are no
obvious oil leaks, drive to the nearest
service station to refill the engine oil
should be topped to the required level.
For information on approved engine oils,
refer to the Factory Approved Service
Products pamphlet (USA only) or contact
an authorized Mercedes-Benz Center.
Left displayRight displayPossible cause/consequencePossible solution
NUSA only:
Add 1 qt
engine oil
at next
refueling.
Canada only:
Add 1 liter
engine oil
at next
refueling.
Vehicles with engine oil measuring
system only:
The engine oil level is too low.Add engine oil (page 286) and check the
engine oil level (
page 284).
!Engine oil level warnings should not be ig-
nored. Extended driving with the symbol
displayed could result in serious engine damage
that is not covered by the Mercedes-Benz
Limited Warranty.