Jaguar XK JJM 18 02 30 701 - Manual (Page 145)

Brakes
162
L
Brakes
PRINCIPLE OF OPERATION
Anti-lock braking system (ABS)
!
WARNING:
• It remains the driver’s responsibility
to drive safely according to
prevailing conditions.
• The fact that a vehicle is fitted with
ABS must never allow the driver to
be tempted into taking risks which
could affect his or her safety or that
of other road users.
• 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.
• 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.
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 tire and
road adhesion.
ABS optimises tire to road adhesion
under maximum braking conditions
though it cannot provide increased
cornering ability.
During normal braking the ABS will not be
activated. However, if the braking force
applied begins to exceed tire to 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 tire
and road adhesion.
Under severe braking on some road
surfaces tire noise may be apparent even
though the wheels will at no time become
locked.
ABS monitoring
Caution: Consult a Jaguar Dealer
immediately if the warning light comes
on while driving, a system failure is
indicated.
The ABS control module monitors the
ABS electrical system from ignition switch
ON to ignition system OFF. Any
malfunction will be indicated by the
anti-lock warning light coming on and a
message ABS FAULT will be displayed
by the message centre.
Should a fault develop in the ABS system,
the brake system will still operate
conventionally and with the same
standard of performance as vehicles not
equipped with ABS.