FORD 2003 F-550 v.1 - Manual (Page 103)

emergencystops bykeeping the rear brakes from locking. The front
wheels, however, maystill lock since theyare not controlled bythe
RABS. Noise from the ABS pump motor and brake pedal pulsation may
be observed during ABS braking; this is normal.
RABS warning lamp
The
ABS
warning lamp in the instrument cluster momentarilyilluminates
when the ignition is turned to the ON position. If the light does not
illuminate momentarilyat start up, remains on or continues to flash, the
ABS needs to be serviced.
With the ABS light on, the anti-lock
brake system is disabled and normal
braking is still effective unless the
brake warning light also remains
illuminated with parking brake released. (If your brake warning lamp
illuminates, have your vehicle serviced immediately.)
Using RABS
In an emergency, applying full pressure may cause the front wheels to
lock. If the front brakes lock, the vehicle cannot be steered. You
should applythe brakes with steadilyincreasing force, as if “squeezing”
the brakes. If you feel the front wheels begin to lock, momentarily
release the pedal and repeat the “squeeze” technique.
Four-wheel anti-lock brake system (ABS) (if equipped)
Your vehicle maybe equipped with an Anti-lock Braking System (ABS).
This system helps you maintain steering control during emergency stops
bykeeping the brakes from locking. Noise from the ABS pump motor
and brake pedal pulsation maybe observed during ABS braking; any
pulsation or mechanical noise you may feel or hear is normal.
ABS warning lamp
ABS
The ABS lamp in the instrument cluster momentarilyilluminates when
the ignition is turned to ON. If the light does not illuminate during start
up, remains on or flashes, the ABS maybe disabled and the ABS may
need to be serviced.
Even when the ABS is disabled,
normal braking is still effective. (If
your BRAKE warning lamp
illuminates with the parking brake
released, have your brake system serviced immediately.)
Driving
103