Raytheon Beech Baron E55 - Page 552

BARON
55
AND
58
SHOP
MANUAL
CHART
6
TROUBLESHOOTING
THE
PROPELLER
DEICER SYSTEM
Indication
Probable
Cause
Remarks
1.
Ammeter
shows
zero
current.
a.
Switch
circuit
breaker
tripped.
a.
Locate and
correct
the short before
(All
four
phases
of
the
two-minute
restoring
circuit breaker
by
turning
cycle.) ton
McCauley
installation
switch
OFF,
then
ON.
both
phases
of
a
3-minute
cycle)
b.
Switch
Faulty.
b.
If
no
voltage
at
switch
output
with
voltage
at
switch
input, replace
the
switch.
If
voltage
is
ok
at
switch
output,
go
to
step
d.
c.
No
power
from
airplane.
c.
If
no
voltage
into
switch,
locate and
correct
open
circuit.
d. Ammeter
faulty.
(If
some or
all d, lest
for
voltage
up
to
and
out
of
deicers heat
with
ammeter at
ammeter.
If
low
or
zero
output
but
zero,
replace
ammeter.)
proper
input, replace
ammeter.
If
no
voltage
to
ammeter,
locate and
fix
open
between
switch and
ammeter.
e.
Open
circuit
ammeter
and
e.
Disconnect
harness
at
timer
and
timer.
check
voltage
pin
B
(of harness)
to
ground.
If
none
locate
and
correct
open
circuit.
2.
Ammeter
shows
normalcurrent
a.
Open
in
wiring
between
timer
a.
Refer
to
paragraph
on
heat
test
to
part
of
cycle,
zero
current rest
of
and firewall
connector,
find
deicers
not
heating
and
test
for
cycle.
voltage
on
that
pin
of
firewall
connector.
If
zero over
2
minutes
(3
minutes
on
McCauley),
Locate
and
fix
open
in
wiring
from
timer
to
firewall.
b.
Open
between firewall and b.
If
voltage
ok
to
firewall
plug,
try
deicer
lead
strap.
voltage
at
junction
of deicer
lead
and
slip
ring
lead.
If
no
voltage,
find and
correct
open
in
wiring
to
brush
block,
open
within brush
block,
or
brush
with
no
contact
to
slip
ring.
c.
No
ground
circuit.
c.
If
voltage
at
deicer
leads,
locate
and
fix
open
from
deicer
to
ground.
3.
Ammeter
shows
normal
current
a.
Inner and
outer
deicers
heating
a.
Locate
and
repair
incorrect
part
of
cycle,
low
current
rest
of
same
phase
(B.
F.
Goodrich
connections.
cycle,
only).
b.
Open
in
deicer
or
slip
ring.
b.
Disconnect
deicer
straps
to
check
heater
resistance.
If resistance
is within
specified
limits,
locate
and
fix
open
in
slip ring
leads.
If
not,
replace
deicer
with
open
circuit.
c.
High
resistance
in
circuit
with
c.
If
no
brush-to-slip-ring
contact
low
current.
(including
ground
brush),
trace
wiring
to
deicer
and
to
timer
to
fix
partial
or
broken
wire,
loose
or
corroded
connections.
11-72
E15