Page 324 of 425

323 Practical hints
What to do if ...
Left displayRight displayPossible cause/consequencePossible solution
PGear selector
lever to PYou wish to start the engine and the
selector lever is not in park
positionP.Move the selector lever to park positionP.
Shift to Nto startMove the selector lever to neutral
positionN.
SLRACL malfunction
Visit
workshopThe locking system is
malfunctioning.
The transmission cooling system
is malfunctioning.
Have the system checked at an authorized
Mercedes-Benz Center immediately.
SRSRestraint
system malfunction
Visit
workshopThere is a malfunction in the supple-
mental restraint systems. The
air bags or emergency tensioning de-
vices (ETDs) could deploy unexpect-
edly or fail to activate in an accident.Drive with added caution and have the
system checked at an authorized
Mercedes-Benz Center immediately.
Warning!G
In the event that a malfunction of the SRS is
indicated as outlined above, the SRS may
not be operational. For your safety, we
strongly recommend that you contact an
authorized Mercedes-Benz Center
immediately to have the system checked;
otherwise the SRS may not be deployed
when needed in an accident, which could re-
sult in serious or fatal injury, or it might de-
ploy unexpectedly and unnecessarily which
could result in an accident and/or injury to
you or to others.
Page 329 of 425

328 Practical hints
What to do if ...
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 capability.
Considerably greater brake
pedal force is required and the
pedal travel is longer. The stop-
ping distance is increased. If
necessary, apply full pressure
to the brake pedal.
Stop the vehicle immediately in a safe location 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 imme-
diately. Adjust driving to be consistent with reduced
braking responsiveness.
Read and observe additional messages in the
multifunction display.
The starter battery has been
charged with a battery charger
or jump started.Contact an authorized Mercedes-Benz Center.
There is a malfunction in the
electronic system.Have the system checked at an authorized
Mercedes-Benz Center immediately.
Page 331 of 425
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.
Page 334 of 425
333 Practical hints
What to do if ...
Left displayRight displayPossible cause/
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.
Page 336 of 425

335 Practical hints
What to do if ...
Left displayRight displayPossible cause/
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.
Page 337 of 425
336 Practical hints
What to do if ...
Left displayRight displayPossible cause/
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)
Page 340 of 425
339 Practical hints
What to do if ...
Left displayRight displayPossible cause/
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.
Page 397 of 425

396 Technical data
Fuels, coolants, lubricants, etc.
Anticorrosion/antifreeze
Your vehicle contains a number of alumi-
num parts. The use of aluminum compo-
nents in motor vehicle engines
necessitates that anticorrosion/antifreeze
coolant used in such engines be specifical-
ly formulated to protect the aluminum parts. Failure to use such anticorro-
sion/antifreeze coolant will result in a
significantly shortened service life.
Therefore, the following product is strongly
recommended for use in your vehicle:
MB 325.0 Anticorrosion/Antifreeze agent.Before the start of the winter season (or
once a year in hot southern regions), you
should have the anticorrosion/antifreeze
concentration checked. The coolant is also
regularly checked each time you bring your
vehicle to an authorized Mercedes-Benz
Center for service.
Anticorrosion/antifreeze quantity
Approximately freeze protection
-35°F (-37°C)-49°F (-45°C)
Main cooling system5.2 US qt (5.0 l)5.8 US qt (5.5 l)
Low temperature cooling system
Mercedes-Benz SLR McLaren2.6 US qt (2.5 l)2.9 US qt (2.75 l)
Mercedes-Benz SLR McLaren 722 Edition3.2 US qt (3.0 l)3.5 US qt (3.3 l)