Piper PA-32R-301T SARATOGA S, Maintenance Manual

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FLIGHT COMPARTMENT
INSTRUMENT AND PANEL LIGHTS
Instrument and panel lights are broken up into five groups; Upper Panel Lights, Lower Panel Lights,
Console Lights, Coupler Lights and Compass Light. Instrument lights are controlled by a 5 amp circuit
breaker through a transistorized dimmer. Dimmer control is located in middle of instrument panel just
above pedestal. There is one control knob connected to a variable resistor that controls intensity of
instrument lights. There is a second control knob connected to a variable resistor which controls light
intensity for all avionic equipment. It may be necessary to gain access to Dimmer Control Assembly; if so
follow instructions given below.
REMOVAL OF DIMMER CONTROL ASSEMBLY
1. Access to Dimmer Control Assembly is from beneath instrument panel.
2. Disconnect electrical connection from assembly.
3. Remove two screws securing assembly to instrument panel.
4. Remove assembly from airplane.
INSTALLATION OF DIMMER CONTROL ASSEMBLY
1. Position assembly in instrument panel with control knobs inserted into appropriate slots.
2. Secure assembly to instrument panel with two screws previously removed.
3. Connect electrical connection to assembly.
4. Check operation of Dimmer Control Assembly.
ANNUNCIATOR PANEL
The annunciator panel is a small cluster of lights which warn of malfunctions in various circuits or systems.
A malfunction is identified by illumination of an individual warning light. There are three warning lights
on PA-32R-301 SP models, four warning lights on PA-32R-301T SP models, and six to eight warning
lights (depending on installed options) on PA-32R-301 II HP models. Power is supplied from bus bar
through a 5 amp fuse located behind circuit breaker panel.
VAC warning light is controlled by a vacuum sensor switch located at bulkhead and is attached to vacuum
regulator. Sensor switch will activate when differential pressure is below 3.5 in. hg.
OIL warning light is controlled by an oil pressure sensor switch incorporated in oil line to oil pressure
gauge and is located at bulkhead. Sensor switch will activate when oil pressure is below 35 psi.
ALT warning light is illuminated by current flowing from bus bar to alternator circuit. This condition
exists when alternator is not operating properly and output is zero. During normal operation, alternator
warning circuit is also supplied with power from top diode terminal. This current flows through a 5 amp
fuse, located above diode heat sink, to resistor and diode creating a no-flow condition which does not
allow warning light to light.
OVERBST warning light used on PA-32R-301T is activated whenever engine manifold pressure reaches
35.5 to 35.8 inches of mercury. Manifold pressure sensor is incorporated in manifold pressure gauge.
FLAP annunciator (PA-32R-301 II HP only) lights whenever a new flap position is selected and remains
on while the flaps are in transient
PIPER AIRCRAFT
PA-32R-301/301T
MAINTENANCE MANUAL
33-10-00
Page 33-5
Reissued: July 1, 1993
3E6