Chrysler 2004 Pacifica - Manual (Page 210)

When the vehicle is driven over 7 mph (11 km/h), you
may also hear a slight clicking sound as well as some
related motor noises. These noises are the system per-
forming its self check cycle to ensure that the ABS system
is working properly. This self check occurs each time the
vehicle is started and accelerated past 7 mph (11 km/h).
ABS is activated during braking under certain road or
stopping conditions. ABS-inducing conditions can in-
clude ice, snow, gravel, bumps, railroad tracks, loose
debris, or panic stops.
You also may experience the following when the brake
system goes into Anti-lock:
• The ABS motor running (it may continue to run for a
short time after the stop),
• the clicking sound of solenoid valves,
• brake pedal pulsations,
• and a slight drop or fall away of the brake pedal at the
end of the stop.
These are all normal characteristics of ABS.
WARNING!
The Anti-Lock Brake System contains sophisticated
electronic equipment that may be susceptible to
interference caused by improperly installed or high
output radio transmitting equipment. This interfer-
ence can cause possible loss of anti-lock braking
capability. Installation of such equipment should be
performed by qualified professionals.
All vehicle wheels and tires must be the same size and
type and tires must be properly inflated to produce
accurate signals for the computer.
210 STARTING AND OPERATING