2008 MERCEDES-BENZ SL65AMG Owner's Manual

376 Practical hints
What to do if …
Symbol messages
Left displayRight displayPossible cause/consequencePossible solution
# The battery is no longer charging.
Possible causes:

alternator malfunctioning

broken poly-V-belt
Do not forget that the brake system
requires electrical energy and may
be operating with restricted capa-
bility. Considerably greater brake
pedal force is required and the stop-
ping distance is increased.
Stop the vehicle immediately in a safe loca-
tion and 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 in order:
Contact an authorized Mercedes-Benz
Center immediately. Adjust driving to be
consistent with reduced braking respon-
siveness.
There is a malfunction in the elec-
tronic system.Have the system checked at an authorized
Mercedes-Benz Center as soon as possible.

377 Practical hints
What to do if …
Left displayRight displayPossible cause/consequencePossible solution
# Battery/
Alternator
Stop CarThe battery is malfunctioning.
The electro-hydraulic brake system
requires electrical energy and
therefore has only limited opera-
tion. Considerably greater brake
pedal force is required and the stop-
ping distance is increased.Stop the vehicle in a safe location.
Adjust driving to be consistent with reduced
braking responsiveness.
Contact an authorized Mercedes-Benz
Center.
USA only:
;
Canada only:
3
Reduced
Brake Effect
Start EngineThe battery has insufficient voltage
and cannot supply sufficient power
to the electro-hydraulic brake sys-
tem.Start the engine.
The message disappears when sufficient
voltage is available.
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 lead to death. Do not
run the engine in confined areas (such as a
garage) which are not properly ventilated.

378 Practical hints
What to do if …
Left displayRight displayPossible cause/consequencePossible solution
TReduced
Brake Effect
Depress brake
pedal fully.The electro-hydraulic brake system
is in emergency operation mode.
Considerably greater brake pedal
force is required and the brake
pedal travel is longer. The stopping
distance is increased.
The maximum speed is limited to
55 mph (90 km/h).Stop the vehicle in a safe location or as soon
as it is safe to do so.
Apply the parking brake (page 63).
Do not drive any further.
Prevent the vehicle from rolling away by
blocking the wheels with wheel chocks or
other sizeable objects.
Contact an authorized Mercedes-Benz Center
or call for Roadside Assistance (
page 253).
Warning!G
Driving while this message is 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
further 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 434).

379 Practical hints
What to do if …
Left displayRight displayPossible cause/consequencePossible solution
USA only:
;
Canada only:
3
Reduced
Brake Effect
Service
RequiredThe electro-hydraulic brake system
is in emergency operation mode.
Considerably greater brake pedal
force is required and the brake
pedal travel is longer. The stopping
distance is increased.Stop the vehicle in a safe location or as soon
as it is safe to do so.
Apply the parking brake (page 63).
Do not drive any further.
Prevent the vehicle from rolling away by
blocking the wheels with wheel chocks or
other sizeable objects.
Contact an authorized Mercedes-Benz Center
or call for Roadside Assistance (
page 253).
Warning!G
Driving while this message is 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
further 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 434).

380 Practical hints
What to do if …
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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.

381 Practical hints
What to do if …
Left displayRight displayPossible cause/consequencePossible solution
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.

382 Practical hints
What to do if …
Left displayRight displayPossible cause/consequencePossible solution
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).

383 Practical hints
What to do if …
Left displayRight displayPossible cause/consequencePossible solution
•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)