Raytheon Beech Baron E55 - Page 553

BARON
55
AND
58
SHOP MANUAL
CHART
6
TROUBLESHOOTING
THE
PROPELLER DEICER
SYSTEM
(Continued)
Indication
Probable Cause Remarks
4.
Ammeter
shows
low
current
a.
Airplane
voltage
low.
a.
Check
voltage
into
switch.
over
entire
cycle.
b. Ammeter
faulty.
b.
Refer
to
step
Id.
c.
High
resistance
up
to
timer.
c.
Check
for
partial
broken
wire,
loose
or
corroded connection
in
wiring
from
airplane supply
to
timer
input.
5.
Ammeter
shows
excess
current
a.
Ammeter
faulty,
a.
Refer
to
step
Id.
over
entire
cycle.
b.
Ground
between
ammeter
and
b.Disconnect harness at
timer and
timer. check from
pin
B
(of
harness)
to
ground
with
an
ammeter.
If
ground
is
indicated,
locate and
correct
6.
Ammeter
shows
normal
current
a.
Ground
between brush block
a.
Disconnect
leads
at
brush block and
part
of
cycle,
excess
current
rest
and timer,
check from
power
leads
to
ground
with
of
cycle.
ohmmeter.
If
ground
is
indicated,
locate
and
correct.
b.
Ground
between brush
block
b. If
no
short exists
at
brush
slip
ring
and
deicers
(excluding
ground
contact,
check for
ground
from
slip
ring
brush
circuit).
lead
to
bare
prop
while
Rexing slip ring
and deicer leads.
If
a
ground
is
indicated,
locate and
correct.
c.
Short between
two
adjacent
c.
Check
for shorts
or
low
resistance
circuits.
between
circuits;
if
any,
locate
and
correct.
d.
Timer
faulty.
d. Test
timer
as
indicated
in
paragraph
on
timer
check.
7.
Ammeter does
not
"flick" each
a.
Timer
ground
open,
a.
Disconnect
harness at timer
and
30
seconds
(90
seconds
on
check with ohmmeter
from
pin
G
(of
McCauley
installations)
harness)
to
ground.
If
no
circuit,
refer
to
wiring diagram
in
Section
14
to
fix
open
circuit.
b.
Timer
contacts
are
welded b.
Test
timer
as
in
paragraph
on
timer
(caused
by
short circuit in check. If timer does
not
cycle
with
system),
voltage
at
pin
B,
replace
timer but
be
sure
short
causing
original
failure has
been located
and
corrected.
3.
Ammeter
"flicks" between
30
a.
Loose connection between
a.
If
trouble
occurs
over
entire
cycle,
seconds
phase
periods
(90
airplane
power
supply
and timer
trace
wiring
from
power
source
to
timer
seconds
on
McCauley
input, input
to
locate and
tighten
loose
installations).
connections.
E15
11-73