V50 w646.book - ESD - Volvo

06 Starting and driving
Brake system
06
Brake servo
If the car is rolling or is being towed with the
engine turned off, the brake pedal must be
pressed about five times harder than when
the engine is running. If the brake pedal is
pressed when the engine is started, you will
feel the pedal drop. This is normal and due to
the brake servo becoming active. This may
be more noticeable if the car has emergency
brake assistance (EBA).
WARNING
The brake servo only works when the engine
is running.
NOTE
If braking with the engine switched off,
press the brake pedal sharply once, not repeatedly.
Brake circuits
This symbol lights if a brake circuit
is not working.
If a fault should occur in one of the
circuits, it is still possible to brake
the car. The brake pedal will travel further
and may feel softer than normal. Harder
pressure on the pedal is needed to produce
the normal braking effect.
Dampness can affect braking characteristics
Brake components become wet when the
car is driven in heavy rain, through pools of
water or when the car is washed. This may
alter brake pad friction characteristics so that
there is a delay before braking effect is noticed.
Press the brake pedal lightly from time to
time if driving for long stretches in rain or
slushy snow, as well as after setting off in
very damp or cold weather. This warms up
the braking surfaces and dries off any water.
It is also recommended to do this before
parking the car for a long period in such
weather conditions.
If the brakes are used heavily
When driving in the Alps or other roads with
similar characteristics, the car’s brakes are
heavily loaded even if the brake pedal is not
being depressed especially hard.
Because speed is often low, the brakes are
not cooled as effectively as when driving on
flat roads at higher speed.
So as not to overload the brakes, shift down
when driving downhill instead of using the
foot brake. Use the same gear driving downhill
as you would use driving uphill. This uses
engine braking more efficiently and requires
the foot brake for only brief periods.
Bear in mind that driving with a trailer puts an
additional load on the car’s brakes.
Anti-lock braking system (ABS)
The anti-lock braking system (ABS)
prevents the wheels from locking
up under braking.
This means the ability to steer is
maintained and it is easier to swerve to avoid
a hazard, for example.
After the engine has been started, the ABS
will perform a brief self-test at a speed of
about 20 km/h. This can be felt and heard as
pulses in the brake pedal.
To get the most out of the ABS:
1. Depress brake pedal with full force. Pulses
will be felt.
2. Steer the car in the direction of travel.
Do not release the pressure on the
pedal.
Practice braking with the ABS system in a
traffic-free area and in different weather conditions.
The ABS symbol illuminates for two seconds
if there was a fault in the ABS system when
the engine was last running.
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