Piper Navajo PA-31 Service Manual page 677

Bypass valve sticking.
Inoperative servo
actuator.
Low pneumatic pres-
sure.
PIPER NAVAJO SERVICE MANUAL
TABLE X-III.
TROUBLESHOOTING CHART (PRESSURE SYSTEM) (cont.)
Trouble
Cause
Remedy
All switching operates
properly, but AutoPilot
is inoperative.
No pressure at servo
actuators.
Check for clogged or
disconnected lines.
Blow out lines.
Check valve - replace
if required.
Replace servo.
Adjust pressure
reg-
ulator.
INSTRUMENTS
Reissued: 10/12/79
3E15