warning lights FORD SUPER DUTY 2004 1.G Diesel Supplement Manual

Air filter restriction gauge (if equipped)
The restriction gauge, located on
the upper housing of the air cleaner
assembly, monitors the condition of
the air filter element in two ways:
•First, the colored indictor inside
the gauge highlights the
percentage that the air filter
element is clogged with dust or
contaminants. Refer to
Maintenance and specifications
chapter.
•Second, the gauge contains an electrical switch which illuminates a
warning light on the instrument cluster when the air filter element is
100% clogged. Refer to theEngine air filterwarning light in this
section of the supplement.
Check the air filter restriction gauge whenever the hood is raised to
perform general engine maintenance at least every 12,000 km (7,500
miles). If the vehicle is operated in extremely dusty conditions, check
the gauge at least every 800 km (500 miles), or two weeks, whichever
comes first.
Instrumentation
8