Cessna 172 - Circuit Breakers and Fuses; Lighting Equipment

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alternator. The red warning light will then turn on, indicating to the
pilot that the alternator is not operating and the aircraft battery is supply-
ing all electrical power.
· The over-voltage sensor may be reset by turning the master switch
off and back on again. If the warning light does not illuminate, normal
alternator charging has resumed; however, if the light does illuminate
again, a malfunction
has occurred, and the flight should be terminated
as soon as practical.
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The over-voltage warning light may be tested by momentarily turning
off the A LT portion of the master switch and leaving the BAT portion
turned on.
CIRCUIT BREAKERS AND FUSES.
The majority of electrical · circuits in the aircraft are protected by
"push-to-reset" circuit breakers mounted on the instrument panel. Ex-
ceptions to this are the optional 'clock and flight hour · recorder circuits, .
and the
battery cont actor closing (external power) circuit which have fuses
mounted adjacent to
the battery. Also, the cigar lighter is protected by a
manually r'
eset type circuit breaker mounted directly on the back of the
lighter behin~ the instrument panel. ·
When
more than one radio is installed, the radio transmitter relay
(which
is a part of the radio installation) is protected by the navigation
lights circuit breaker labeled NAV LT. It is important to remember
that any malfunction in the navigation lights system which causes the cir- ,
cuit breaker to open will de-activate both the navigation lights and the
transmitter relay. In this event, the navigation light switch should be
turned off to is .olate the circuit; then reset the circuit breaker to re-
activate the transmitter relay and permit its usage. Do not turn on the
navigation lights switch until the malfunction
has been corrected.
LIGHTl . NG EQUIPMENT.
EXTERIOR LIGHTING.
Conventional navigation lights are located on the wing tips and top of
the rudder. Optional lighting includes a single landing light or dual
landing/taxi lights in the cowl nose cap, a flashing beacon on the top of
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