TM 3-6665-302-34
(5) Remove switch (23) from bottom of
3-72. Branched Wiring Harness
panel (37).
a. Removal.
b. Installation.
(1) Disassemble M42 alarm unit (para 3-
(1) Position switch (23) with shaft and tab
62).
in mounting holes in panel (37).
(2) Separate battery retainer assembly (29,
(2) Install and tighten boot (12) on shaft
of switch (23).
(3) Remove circuit card assembly (para 3-
(3) Turn switch shaft to the fully clockwise
67a).
position.
(4) Unsolder wiring harness leads loud-
(4) Position knob (11) on switch shaft with
speaker (25), terminals E3 and E4 on terminal
knob pointer at HORN ON position on panel
board (21), switch (23), indicator light (4),
(37).
and battery retainer assembly (29).
(5) Tighten setscrews (10).
(5) Remove screws (14), washers (34),
lockwashers (33), and nuts (32).
(6) Connect and solder tagged wires to
selector switch terminals (View C). Coat sol-
(6) Remove branched wiring harness (35).
dered connections with sealant from coating kit
b. Installation.
(item 6, table 1-1).
(1) Dress leads of branched wiring harness
(7) Assemble M42 alarm unit (para 363).
(35 ) near their respective terminals.
3-71. Battery Retainer Assembly
(2) Secure connector (36) to mounting
bracket on panel (37) with screw (14), washer
(34), lockwasher (33), and nut (32).
a. Removal.
(3) Using the schematic diagram (fig. 2-3)
(1) Disassemble M42 alarm unit (para 3-
connect and solder branched wiring harness (35)
62).
to components mounted on panel (37).
(2) Remove four batteries (TM 3-6665-
(4) Check continuity of wire connections.
22512).
Coat soldered connections with sealant from
(3) Remove four screws (1).
coating kit (item 6, table 11).
(4) Separate battery retaining assembly
(5) Install circuit card assembly (para 3-
(29) from panel (37) to expose soldered connec-
67b).
tions.
(6) Assemble M42 alarm unit (para 3-63).
NOTE
Terminal reference designations XTB1-
1 and XTB42 are molded on the exter-
3-73. Identification Plate
ior of the battery retainer assembly.
a. Pry identification plate (13) from panel
(5) Unsolder black wire from XTB1-1
(37).
terminal and red wire from XTB4-2 terminal.
b. Clean surface of panel (37) with a damp,
Remove battery retainer assembly (29).
clean cloth.
b. Installation.
c. Stamp replacement identification plate with
(1) Connect and solder red wire to XTB4-2
lot number and serial number.
terminal and black wire to XTB11 terminal
on battery retainer assembly (29).
water for approximately 1 minute.
(2) Secure battery retainer assembly (29)
to panel (37) with screws (1).
e. Remove protective backing from replacement
identification plate.
(3) Install four batteries (TM 3-6665-
2512).
f. Press identification plate (13) firmly on
(4) Assemble M42 alarm unit (para 3-63).
panel (37).
