Piper Warrior III - Page 286

PIPER AIRCRAFT, INC.
PA-28-161, WARRIOR III
MAINTENANCE MANUAL
2D20
24-30-00
PAGE 4
Nov 30/06
CHART 1 (Sheet 1 of 5)
TROUBLESHOOTING ALTERNATOR SYSTEM
Trouble Cause Remedy
Zero output indicated Open field circuit With the master switch
on ammeter regardless turned on, check for battery
of rpm (see alternator voltage from the airplane’s
test, 24-30-00). main bus through the entire
field circuit to the alternator
field terminal. Measure the
voltage from the ground (-)
to the following points (+) in
sequence: bus bar, field
circuit breaker (5A), field
terminals of master switch,
voltage regulator, and
alternator field terminal.
Interruption of voltage
through any of these points
isolates the faulty
component or wire which
must be replaced.
(See wiring schematic,
Chapter 91.)
Open output circuit With the master switch
turned ON, check for
battery voltage from the
airplane’s main bus through
the entire output circuit to
the alternator battery post.
Measure voltage from
ground (-) to the following
points (+) in sequence:
bus bar, output current
limiter, ammeter, and
alternator battery post.
Interruption of voltage
through any of these points
isolates the faulty
component or wire which
must be replaced.
(See wiring schematic,
Chapter 91.)
Open circuit in alternator
output will usually burn out
ALT annunciator and the 50
ohm resistor. Check 5.0
amp in-line fuse.