Ford 2003 Excursion Owner's Manual page 11

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.
Check fuel cap (if equipped)
Illuminates when the fuel cap is not
installed correctly. Check the fuel
cap for proper installation. When
the fuel filler cap is properly
re-installed, the light(s) will turn off
after a period of normal driving.
Continuing to operate the vehicle with the check fuel cap light on, or a
mis-installed fuel cap can activate the Service Engine Soon/Check
Engine warning light.
It may take a long period of time for the system to detect an
improperly installed fuel filler cap.
For more information, refer to Fuel filler cap in the Maintenance and
specifications chapter.
Check gage
Illuminates when the engine coolant
temperature is high, the engine oil
pressure is low or the fuel gauge is
at or near empty. Refer to Engine
coolant temperature gauge, Engine oil pressure gauge or Fuel gauge
in this chapter for more information.
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
Instrument Cluster
CHECK
GAGE
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