MERCEDES-BENZ SLR 2007 R199 Owner's Manual

330 Practical hints
What to do if ...
Left displayRight displayPossible cause/
consequencePossible solution
;(USA only)
3(Canada only)
Check
brake fluid levelRisk of accident!
There is insufficient brake fluid
in the reservoir.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 can 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.

331 Practical hints
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consequencePossible solution
;(USA only)
3(Canada only)
Reduced
brake effect
Visit
workshopThe electro-hydraulic
brake system is in emer-
gency operation mode.
Considerably greater
brake pedal force is
required and the pedal
travel is longer. The stop-
ping distance is in-
creased. If necessary,
apply full pressure to the
brake pedal.Stop the vehicle in a safe location or as soon as it is
safe to do so.
Apply the parking brake (page 55).
Do not drive any further.
Prevent the vehicle from rolling away by blocking the
wheels with wheel chocks or other sizable objects.
Contact an authorized Mercedes-Benz Center.
or
Call for Roadside Assistance.
Increased
stopping distance
Visit
workshop
Warning!G
Driving while these messages are displayed
can result in an accident. Have your brake
system checked immediately.
If the electro-hydraulic brake system enters
its emergency operation mode, the driver
must apply significantly greater brake pedal
pressure and depress the pedal much fur-
ther than normal to obtain braking effect.
If necessary, apply full pressure to the brake
pedal. Brakes are only 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, see “Towing the vehicle”
(
page 370).

332 Practical hints
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consequencePossible solution
;(USA only)
3(Canada only)
Reduced
brake effect
Start engineThe battery has insufficient
voltage and cannot supply
sufficient power to the
electro-hydraulic brake system.
Considerably greater brake
pedal force is required and the
pedal travel is longer. The
stopping distance is increased.Start the engine.
As soon as the engine is running, the message
disappears.
Increased
stopping distance
Start engine
Warning!G
Inhalation of exhaust gas is hazardous to
your health. All exhaust gas contains carbon
monoxide (CO), and inhaling it can cause
unconsciousness and possible death.
Do not run the engine in confined areas
(such as a garage) which are not properly
ventilated.

333 Practical hints
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consequencePossible solution
;(USA only)
3(Canada only)
Brakes overheated
Drive on, but with
even greater careThe 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.
Use the engine’s braking power more frequent-
ly. Shift into a lower gear (
page 174).
Cautiously continue driving so that the air
stream will cool down the brakes.
The message disappears after driving carefully
for a few minutes.
Warning!G
Overheating of the brake system will short-
en the service life of the brake disks. The
brake disks could fail. Have the brake disks
checked at an authorized Mercedes-Benz
Center.

334 Practical hints
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consequencePossible solution
;(USA only)
3(Canada only)
Service brake
Visit
workshopThere are malfunctions, but the
electro-hydraulic brake system
is operating normally.Contact an authorized Mercedes-Benz Center
immediately.
Release
parking brakeYou are driving with the parking
brake set.Release the parking brake (page 49).
2 Brake wearThe brake pads have reached
their wear limit.Have the brake pads replaced as soon as pos-
sible.
!Brake pad thickness must be visually
checked by a qualified technician at the intervals
specified in the Maintenance Booklet.
Excessive load on the brake system causes in-
creased wear of brake pads and brake disks. If
the brake pads have to be replaced multiple
times within one maintenance service interval,
the brake disks must be checked. Observe the
information given in the Maintenance Booklet
and contact an authorized Mercedes-Benz
Center.Warning!G
Have brake pad replacement and other work
on the electro-hydraulic brake system car-
ried out by qualified technicians only. Con-
tact your Mercedes-Benz Center for further
information. The electro-hydraulic brake
system must be deactivated prior to working
on the system. High pressure is intermit-
tently 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 passenger door is opened, when
the SmartKey in the starter switch is turned
to position1, when the brake pedal is
depressed or when the parking brake is
released.
Failure to deactivate the system prior to
maintenance will cause brake pistons to
extend and brake fluid to leak, which may
result in injuries (contusions and acid
burns), see “Electro-hydraulic brake sys-
tem” (
page 86).

335 Practical hints
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consequencePossible solution
BTop up
coolant
See Oper. ManualThe coolant level is too low.Add coolant (page 255).
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
immediately.
•The cooling fan for the coolant
is malfunctioning.Observe the coolant temperature gauge in the instru-
ment cluster (
page 29).
If the coolant temperature is under 248°F (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 the 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 cooling system. The engine will overheat
causing major engine damage.

336 Practical hints
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consequencePossible solution
•Coolant
Stop car –

Turn 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 over-
heat 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)

337 Practical hints
What to do if ...
During severe operating conditions and
stop-and-go city traffic, the coolant tem-
perature may rise close to 248°F (120°C).
Left displayRight displayPossible cause/
consequencePossible solution
Observe the coolant temperature gauge in the
instrument cluster (
page 29).
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 which can occur just by open-
ing the hood. Stay away from the engine if
you see or hear steam coming from it.
Stop the vehicle in a safe location away from
other traffic. 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).
Doing so may cause serious engine damage
which is not covered by the Mercedes-Benz
Limited Warranty.

338 Practical hints
What to do if ...
Left displayRight displayPossible cause/
consequencePossible solution
•Differential
overheatedThe differential oil is too hot.Stop your vehicle immediately in a safe location.
Do not drive any further.
Apply the parking brake (page 55).
Wait until the instrument cluster display has cleared.
Otherwise you could damage the rear differential.
!The differential warning should not be
ignored. Extended driving with the symbol
displayed could result in serious rear differential
damage that is not covered by the
Mercedes-Benz Limited Warranty.

339 Practical hints
What to do if ...
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consequencePossible solution
±Visit
workshopCertain electronic systems are
unable to relay information to
the control system. The follow-
ing systems may have failed:

Coolant temperature gauge

Tachometer
Have the electronic systems checked by an authorized
Mercedes-Benz Center immediately.
Fuel system
malfunction
Visit
workshopThe fuel cooling system is
malfunctioning.Contact an authorized Mercedes-Benz Center
immediately.
:Engine oil pressure
Visit
workshopThere is no oil in the engine.
There is a danger of engine
damage.Stop your vehicle immediately in a safe location.
Switch off the engine.
Do not drive any further.
Contact an authorized Mercedes-Benz Center
immediately.
!The engine oil level warning should not be
ignored. Extended driving with the symbol
displayed could result in serious engine damage
that is not covered by the Mercedes-Benz
Limited Warranty.