Raytheon Beech Baron E55 - Page 567

aeechcraft
BARON
55
AND
58
SHOP MANUAL
AUTOPILOT
TROUBLESHOOTING
GUIDE
TContinued)
indication
Probabie
Cause
Remarks
4.
Servo
control
valve
will
not
a.
Improper
vacuum
(pressure)
a.
Adjust
as
outlined
in
this section.
center,
adjustment.
b.
Stickey
valve.
b.
Replace
valve.
5.
Output
voltage
is
inadequate,
a. Pitch/altitude
amplifier
sensor
or
a.
Refer
to
Figure
11-45. Run
a
harness
shorted
or
improperly
continuity
check and check
for
wired,
shorts.
6.
Pressure
switch will
not
make
a.
Defective
pressure
switch
or
not
a.
Replace
pressure
switch.
contact
when
pressure
is
on,
set at
proper pressure.
7.
Output
voltage
one
way
only
on
a.
Servo
control valve shorted
to
a.
Replace
valve.
pitch
and
altitude
channels,
ground.
8.
System
will
not
maintain
trimmed
a.
Servo
control
valve
not
a.
Disconnect
electrical
power.
configuration
even
though
centered
pneumatically
centered.
Center
valve
pneumatically by
use
electricaly,
of differential
gage
to
0.4
in.
Hg.
b. Leak
in
servos
or
improperly
b.
Check
for
leaks
and
rig.
rigged.
c.
Leak
in
pitch/altitude
sensor,
c.
Replace
sensor.
9.
System
will
not
respond
to
a.
Primary
vacuum
(pressure)
not
a.
Adjust
as
outlined
in
this
section.
airspeed
changes.
set
properly.
b. Pitot
pressure
inadequate,
b.
Check
pitot plumbing.
c.
Decay
rate
improperly
adjusted.
Adjust
as
required.
10.
System
will
not
respond
to
a.
Defective
pitch/altitude
amplifier,
a.
Replace
pitch/altitude
amplifier.
up-command
adjustment.
b.
NO
EVT
potentiometer
output.
b.
Replace
turn coordinator.
11.
System
will
not
respond
to
a. Pitch/altitude
amplifier
limiter
a.
Adjust
as
required.
altitude-gain
adjustments,
improperly
set.
12.
Airplane
has
long
term
a.
Decay
rate
improperly
adjusted
a.
Adjust
as
required.
oscillation about
pitch
axis with
altitude hold
OFF.
b.
Pitch/altitude
gain
improperly
b.
Adjust
as
required.
adjusted.
c.
Friction
in elevator
servo or
c.
Check
for friction
and
correct.
system.
13.
Airplane
has
short term
a.
Decay
rate
too
tight.
a.
Adjust
as
required.
oscillation
about
pitch
axis.
b.
Pitch
gain
too
high.
b.
Adjust
as
required.
c.
Primary
vacuum
(pressure)
too
c.
Readjust
as
outlined
in
this
high,
section.
14.
Airplane
oscillates
with
altitude
a.
Altitude
gain
too
high.
a.
Adjust
as
required.
hold ON.
b.
Decay
rate
improperly
adjusted.
b.
Adjust
as
required.
15.
Airplane
does
not
return to
a.
Altitude
hold
solenoid
a.
Replace
solenoid,
altitude when
displaced,
inoperative.
b.
Leak
in
altitude
system.
b.
Check for leaks.
515
11-87