Mercedes-Benz SLR McLaren. Operator's Manual.

Operation
Driving instructions
Power 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 system
operation and switch it into its emergency
operation mode. In such a case, the
red brake warning lamp ( page 300) and
warning messages ( page 307) in the instrument
cluster come on while driving. To
brake, the driver must then apply significantly
greater brake pedal pressure and depress
the pedal much further to obtain the
expected 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 electrohydraulic brake system,
we recommend that the vehicle be transported
with all wheels off the ground using
flatbed or appropriate wheel lift/dolly equipment.
232
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 information,
see “Towing the vehicle”
( page 360).
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 vehicle.
Warning! G
After driving in heavy rain for some time
without applying the brakes or through water
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 effect.
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 effectiveness.
It may not be possible to stop the
vehicle in sufficient time to avoid an accident.