Mooney M20K - Page 138

SERVICE
AND
MAINTENANCE
MANUAL
~1120K
MOONEY
AIRCRAFT
CORPORATION
TROUBLE
SHOOTING
CHART-PROPELLER
DE-ICE
(conY.)
TROUBLE
PROBABLE
CAUSE
REMEDY
Ammeter
shows
0
current
Tn’pped
circuit
breaker.
Locate
and
correct
short
before
all
phases
of
the
timer
cycle.
resetting
circuit
breaker.
Circuit
breaker
or
switch
faulty.
If
no
voltage
at
circuit
breaker
output
with
voltage
at
input
and
circuit
breaker
does
not
reset,
replace
circuit
breaker.
If
voltage
is
OK at
output,
check
switch
in
same
manner.
If
voltage
is
OK
at
switch
output,
90
to
"Ammeter
Faulty".
Ammeter
Faulty
Test
ammeter
per
Section
30-62-00.
Open
ammeter
to
timer.
Disconnect
harness
at
timer
and
check
for
appropn’ate
voltage
at
hamess
Pin
B
(12V);
Terminal
C
(24V)
to
ground.
If
none,
locate
and
correct
open.
Open
timer
to
brush
assembly.
Disconnect
wire
harness
at
brush
assembly
and
check
voltage
to
ground
from
pins
or
leads.
(See
de-icing
system
wiring
schematic
for
power
and
ground
lead
and
pin
identification.)
If
low
or
no
voltage,
locate
and
coreet
open
or
high
resistance
in
wire
harness.
Check
continuity
from
appropriate
pin
or
lead
to
ground;
if
high
resistance
is
indicated,
check
ground
wire
for
breakage
and
ground
connections
for
correctness
and
tightness.
Comet
as
required.
Open
in
De-leer,
DPlcer
wire
Disconnect
De-leer
leads
and
check
hamess
or
slip
ring
assembly
resistance
per
B.F.
Goodrich,
leads.
Report
No.
59-728
If
not
OK,
replace
faulty
De-leer
boot.
If
OK,
check
for(and
repair)
open
in
de-ice
boot
wiring
harness
leads.
See
Section
5-4.5,
8.8.
Goodrich
Report
6&04-7218.
Ohmmeter
needle
must
not
flicker
when
leads
are
stretched
or
flexed.
Replace
as
required.
Open
on
both
ground
brushes.
Remove
brush
block
assembly
and
check
both
ground
brushes
for
continuity
between
the
brush
and
pigtail
lead.
If
an
open
is
found,
repair
brush
block
assembly.
If
OK,
reinstall
and
check
for
proper
face
alignment
and
brush
projection
per
8.8.
Goodrich,
Report
No.
59-728.
30-61-02
OLDWILLWAYNE