FORD 2003 Expedition v.1 - Manual (Page 11)

If the light remains on, have your vehicle serviced at the first available
opportunity.
Light is blinking:
Engine misfire is occurring which could damage your catalytic converter.
You should drive in a moderate fashion (avoid heavy acceleration and
deceleration) and have your vehicle serviced at the first available
opportunity.
Under engine misfire conditions, excessive exhaust temperatures
could damage the catalytic converter, the fuel system, interior
floor coverings or other vehicle components, possibly causing a fire.
Brake system warning
To confirm the brake system
warning light is functional, it will
momentarily illuminate when the
ignition is turned to the ON position
(alternatively for some vehicles when the ignition is moved from the ON
position to START position, the light will momentarily illuminate prior to
reaching the START position). It also illuminates if the parking brake is
engaged. If the brake system warning light does not illuminate as
described, seek service immediately. Illumination after the parking brake
is released indicates low brake fluid level or a brake system malfunction
and the brake system should be serviced immediately by a qualified
technician.
Refer to Brakes in the Driving chapter for more information.
Anti-lock brake system (ABS)
To confirm the anti-lock brake
system (ABS) warning light is
functional it will momentarily
illuminate when the ignition is
turned to the ON position
(alternatively for some vehicles when the ignition is moved from the ON
position to the START position, the light will momentarily illuminate just
prior to reaching the START position). If the light remains on, continues
to flash or fails to illuminate, have the ABS serviced immediately. If the
ABS light remains on, it means the anti-lock brake system has
malfunctioned and is disabled, however, the normal brake system will
still function unless the brake warning light also remains illuminated and
parking brake is off. Refer to Brakes in the Driving chapter for more
information.
ABS
Instrument Cluster
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