4-9.1 Cleaning and Inspection
Wipe clean exterior of alarm relay module with clean rag. Remove front plate and vacuum clean or clean inside
with electrician's brush. Avoid using unauthorized solvents for cleaning inside of alarm relay module. Solvents
leave a greasy film on components that may reduce electrical conductivity.
Visually inspect for indications of bums, corrosion, loose connections, damaged parts, or chipped paint. Clean
corrosion from contacts and terminals, tighten loose connections, and replace damaged parts. Remove
corrosion with silver polish, fine sandpaper, or burnishing tool. Do not use emery paper or emery cloth or steel
wool. Vacuum to remove residue. Touch up paint according to TB 43-0144. Do not paint threads or labels.
If alarm relay module is inoperative, move main power switch to ON (Figure 1-3) and close (ON) circuit breaker
4P14 or 24 Vdc power panel. Check input voltage from keyboard and 24 Vdc power panel. If input voltage
reading from keyboard is not between 25 and 28 Vdc go to step b to check keyboard and cable. If input voltage
from 24 Vdc power panel is not between 25 and 28 Vdc, go to step c to check power source. If both readings are
between 25 and 28 Vdc, go to step d to check alarm relay module.
Check keyboard voltage to alarm relay module. If voltage reading is not between 25 and 28 Vdc, check
keyboard as given in paragraph 4-7. If voltage reading is between 25 and 28 Vdc, check cable 13P13J
connections and continuity Tighten cable connection or repair or replace bad cable between keyboard and alarm
Check 24 Vdc power panel circuit breaker 4P 14 output. If output reading Is not between 25 and 28 Vdc, power
source is at fault Check power source. If output voltage is between 25 and 28 Vdc, check cable 4P14
connections and continuity. Tighten cable connection or repair or replace bad cable between alarm relay module
and 24 Vdc power panel
Check alarm relay module voltage to horn, strobe light and buzzer. If output voltage reading is not 25 to 28 Vdc,
replace fuse as given In paragraph 4-9.3. If after repair, alarm relay module still does not operate, replace
module as given In paragraph 4-9.4. If output voltage is 25 to 28 Vdc, check horn, as given In paragraph 4-11,
strobe light as given in paragraph 4-12, or buzzer as given in paragraph 4-13.
4-9.3 Repair. Repair Involves replacement of fuses.
Remove alarm relay module front plate by loosening four screws.
Remove and replace 1 OA fuse(s) located on center of left and right sides of circuit board c. Replace front plate.
Tag and disconnect cables (13P13J, 4P14, 4P14A, 4P14B, and 4P14C) from alarm relay module.
Remove mounting hardware and remove module.
Install module and secure with mounting hardware.
4-10 Bilge alarm module
Make sure main power switch (Figure 1-3) Is in OFF position and circuit breaker 1P14 on 24
Vdc power panel is open (OFF) when performing maintenance. Redtag switch with:
"WARNING DO NOT ACTIVATE. REPAIRS BEING MADE."