Jaguar JJM 21 02 20/15 Automobile User Manual


 
4-38 On the road
Anti-lock braking
system (ABS)
This system helps to prevent the road
wheels from locking and skidding during
emergency braking, assisting the driver to
maintain full steering and directional
stability.
The factor controlling ultimate stopping
distance and cornering ability is tyre/road
adhesion.
!
WARNING:
1. It remains the driver’s
responsibility to drive safely
according to prevailing
conditions.
2. The fact that a vehicle is fitted with
ABS must never allow the driver to
be tempted into taking risks
which could affect his/her safety or
that of other road users.
3. The addition of ABS cannot
overcome the consequences of
trying to stop in too short a
distance, cornering at too high a
speed, or the risk of aquaplaning.
4. The driver should always take
road conditions into account.
A slippery road surface always
requires more braking distance
for a given speed, even with ABS.
A possible increase in stopping
distance compared to locked
wheels may occur during ABS
operation on slushy snow, gravel,
sand, or some heavily corrugated
or ridged warning sections of road
surfaces.
ABS optimises tyre/road adhesion under
maximum braking conditions though it
cannot provide increased cornering
ability. There is no need for special
braking techniques, such as ‘pumping’
the brakes, to achieve optimum braking
distances and control on poor or slippery
road surfaces. Tyres must be in good
condition to achieve maximum adhesion.
During normal braking the ABS will not
be activated. However, if the braking
force applied begins to exceed tyre/road
adhesion the ABS will automatically
activate, preventing the road wheels from
locking.
In these circumstances a pulsating effect
will be felt from the brake pedal
indicating that the system is functioning.
The pulsating effect is due to small
fluctuations in pressure supplied to the
brakes by the system to maintain full
tyre/road adhesion.
Under severe braking on some road
surfaces tyre noise may be apparent even
though the wheels will at no time become
locked.