Cessna 172R Pilot Operating Handbook page 198

SECTION 7
CESSNA
AIRPLANE & SYSTEMS DESCRIPTION
MODEL 172R
Glareshield lighting is accomplished using a fluorescent light
recessed into the glareshield. This light is controlled by rotating the
GLARESHIELD LT dimmer, located below the nav indicators.
Rotating the dimmer clockwise increases light intensity, and rotating
the dimmer counterclockwise decrease light intensity.
Pedestal lighting consists of a single, hooded light located above
the fuel selector.This light is controlled by rotating the PEDESTAL
LT dimmer, located below the nav indicators. Rotating the dimmer
clockwise increases light intensity,
and rotating the dimmer
counterclockwise decreases light intensity.
Panel lighting is accomplished using individual lights mounted in
each instrument and gauge. These lights are wired in parallel and
are controlled by the PANEL LT dimmer, located below the nay
indicators. Rotating the dimmer clockwise increases light intensity,
and rotating the dimmer counterclockwise decreases light intensity.
Pilot control wheel lighting is accomplished by use of a rheostat
and light assembly, located underneath the pilot control wheel yoke.
The light provides downward illumination from the bottom of the
yoke to the pilot's lap area. To operate the light, first turn on the
NAV light switch, then adjust the map light intensity with the knurled
rheostat knob. Rotating
the dimmer clockwise increases
light
intensity, and rotating the dimmer counterclockwise decreases light
intensity.
Regardless of the light system in question, the most probable
cause of a light failure is a burned out bulb. However, in the event
any of the lighting systems fail to illuminate when turned on, check
the appropriate circuit breaker. If the circuit breaker has opened,
and there is no obvious indication of a short circuit (smoke or odor),
turn off the light switch of the affected light, reset the breaker, and
turn the switch on again. If the breaker opens again, do not reset it.
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Dec 2/96