TM 11-6130-381-14
6-10. Repair of Control Circuit Card Assembly
( 2 ) Upon removal of defective part, use a
chemical stripper to clear an area for the
Remove the control circuit card assembly from the
replacement part.
battery charger per the instructions of paragraph
( 3 ) Flush and clean the reworked area with
Chlorothene V.G. (Federal Specification O-T-620,
coated control circuit card assembly due to surface
Type 1). Dry the area thoroughly.
cracks or broken wires (as indicated by visual in-
CAUTION
s p e c t i o n ) and replacement of defective parts (as
Diodes CR6001 through CR6004, CR6007
i n d i c a t e d by the troubleshooting procedures of
through CR6011, CR6014, CR6015,
CR6017, CR6018, CR6020 through CR6023,
location diagram.
a n d CR6026 through CR6030 are to be
CAUTION
protected with cushioning material prior to
All chemicals prescribed in the following
application of conformal coating.
instructions must be used in an open well
(4) Apply adhesive/sealant RTV 118 to any of
ventilated area. Do not use in presence of
the aforementioned diodes if replacement is
o p e n flame or sparks. Avoid prolonged
required.
c o n t a c t with skin; wash with soap and
(5) Upon installation of new part, apply the
water if contact occurs.
conformal coating over the new part and reworked
NOTE
area, blending it into the existing coating using a
Prior to performing steps a or b b e l o w ,
camel's hair brush.
t h r o u g h l y stir or shake the container of
( 6 ) Allow the assembly to air dry at room
conformal coating. Upon completion of the
temperature until it is no longer tacky. This should
coating procedure, purge the conformal
take approximately 1 hour. The coating will cure
coating container of air to permit storage
hard overnight, and obtain full properties in 5 to 7
a n d later use of the remaining coating
days.
material.
c. Inspection C r i t e r i a for Reworked Board.
a . Removal of Coating from Flat Areas and
Inspect cured board to ensure none of the following
Recoating
conditions exists.
(1) Using a camel's hair brush, dab a chemical
stripper (SNAP, DMF or equivalent) over
( 1 ) Surface cracks or breaks and cracks ex-
tending to the component or inserts.
defective area.
(2) Allow approximately 3 minutes for coating
(2) Improper blending of reapplied coating.
t o loosen. Rub the area, applying additional
(3) Improper curing or drying, as indicated by
stripping material as required with a camel's hair
surface tackiness.
brush, until the coating has become gummy and
(4) Lack of adhesion, as indicated by lifting
loose .
and blisters.
d. Testing. T e s t t h e c o n t r o l c i r c u i t c a r d
( 3 ) Pick away t h e l o o s e n d c o a t i n g w i t h
suitable nonabsorbent probes.
a s s e m b l y in accordance with the procedure in
(4) Clean and flush the area with Chlorothene
V.G. (Federal Specification 0-T-620, Type I).
e. Installation. Install the control circuit card
(5) Dry the area thoroughly.
a s s e m b l y in accordance with the procedure in
( 6 ) Using a camel's hair brush, recoat the
reworked area, blending it into the existing coating
6-11. Testing of Control Circuit Card Assembly
w i t h conformal coating Conathane CE 1164 per
T e s t the control circuit card assembly in ac-
MIL-J-46058.
c o r d a n c e with the procedure of paragraph 6-17
( 7 ) Allow the assembly to air dry at room
through 6-19 except use Charger, Battery
temperature until it is no longer tacky. This should
PP-4127( )/U (NSN 6130-00-782-6983) as the test
take approximately 1 hour. The coating will cure
fixture.
hard overnight, and obtain full properties in 5 to 7
6-12. Repair of Wiring Assembly
days.
b. Removal of Defective Components and
Figure FO-4 depicts point-to-point wiring in-
Recoating
f o r m a t i o n between front panel mounted com-
(1) Apply a suitable heat source [340F (17
p o n e n t s and chassis mounted components of the
C) to 36F (182C) soldering iron or equivalent] to
battery charger subassembly. The chart ac-
fillets of defective coated component. Burn away a
companying the wiring diagram denotes each wire
sufficient amount of conformal coating to allow
comprising the harness by an identifying number,
p a r t to be easily pried from the board. Use a
f r o m and to information. wire color and size.
chemical stripper (SNAP DMF or equivalent to
Comply w i t h the following instructions when
remove coatings from solder connections.
repairing the harness:
6-8
