TM 9-4120-411-14
CHAPTER 5
DIRECT SUPPORT MAINTENANCE INSTRUCTIONS
5.1
CIRCUIT BOARD TESTING AND REPLACEMENT.
THIS TASK COVERS:
a. Testing
b. Removal
c. Installation
INITIAL SETUP:
Tools
Materials/Parts
General Mechanics Tool Kit
Marker Tags (qty 31)
Lock Washers (qty 7)
Lock Washers (qty 16)
WARNING
Rotating parts and lethal voltage levels are used in operating the FDECU. Be sure
power source is disconnected. Injury or death can occur if connected to power
source.
(1) Shutdown the FDECU per paragraph 2.4 and disconnect it from power source.
(2) Loosen eight captive screws (1) an d carefully pull the electrical assembly (2) out.
(3) Support control box panel (3) and remove 16 screws (4), lock washers (5), and flat washers (6). Carefully pull
control box panel away as far as wire leads will allow. Discard lock washers.
(4) Tag two connectors (7) then release locking clip and disconnect from circuit board (8).
(5) Tag and disconnect 29 wire leads (9) from circuit board (8).
NOTE
The center circuit board mounting screw uses two plastic washers to insulate it
from a circuit track on the board.
(6) Remove six screws (10), lock washers (11), and flat washers (12). Discard lock washers.
(7) Remove screw (13), lock washer (14), flat washer (15), plastic flat washer (16), circuit board (8), and plastic flat
washer (17). Discard lock washer.
5-1