TM 55-1520-240-T 16-196     Change 24 16-5.3  AN/ALE-47 COUNTERMEASURES DISPENSER SYSTEM OPERATIONAL CHECK (Continued) 16-5.3 TASK RESULT NOTE Ensure all DCDU INHIBIT LEDs remain illuminated when performing steps 19 – 22. 28.  Press DCDU ENT/BIT switch (25) momentarily to When IBIT is complete, MAINT MODE??? prompt will select maintenance mode. appear. 29. While MAINT MODE??? is displayed, press DCDU The following displays appear:   ENT/BIT switch (25) momentarily to display the DCDU OFP # XXXX   MDF # XXXX   and sequencer firmware identification numbers. CCU FIRM ID #### SEQ 1A ID #### SEQ 2A ID #### SEQ 1A   SAFE SEQ 2A   SAFE 30. When HIST DATA??? appears, press DCDU ENT/BIT   System fault messages are displayed.  Refer to table at switch (23) momentarily. end of this task for explanation of fault messages.  After   fault messages are displayed, CLR FLT LST is displayed. NOTE The number (inventory) displayed on the DCDU will vary based on the number of CDTs being used   to perform the AN/ALE-47operational check. Examples: 1 CDT installed:      10   10   _ _   10 will be displayed 2 CDTs installed:    20   20   _ _   20 will be displayed 3 CDTs installed:    30   30   _ _   30 will be displayed 4 CDTs installed:    40   40   _ _   40 will be displayed 31.  Press DCDU ENT/BIT switch (25) momentarily after O1: 20   O2: 20   CH: _ _   FL: 20 is displayed on DCDU. CLR FAULT LIST? prompt appears to clear the MFL. NOTE The CDT has a battery saver feature which will turn the CDT off after approximately 15 minutes of inactivity. If this occurs, set CDT MODE switch (18) to OFF, then back to FIRE TEST; press RESET TEST button. 32.  Adjust DCDU LED indicator (5) brightness from dim DCDU LED indicator goes from bright to dim as lighting to bright; set as desired using ALE-47 dim switch (2) control switch is rotated. located on miscellaneous control panel (3). TASK RESULT 33.  Press DCDU INHIBIT O1, O2, CH, FL, RWR, JMR,   LED for each switch goes out as switch is   and MWS switches (24). depressed. 34.  Ensure sequencer switches (43 and 44) are set as   follows:  No. 1 sequencer (32): 1/A; No. 2 sequencer (26): 2/A. 35.  Remove safety pin (30) from AN/ALE-47 safety switch (31). 36.  Set LDG GR SW BYPASS switch (28) on LDG GR LDG GR SW BYPASS light (29) on LDG GR BYPASS BYPASS STATUS panel (27) to BYPASS (up). STATUS panel illuminates. If LDG GR SW BYPASS light (29) on LDG GR BYPASS   STATUS panel does not illuminate, troubleshoot per   Task 16-5.13. 37.  Set DCDU MODE switch (7) to MAN and MANUAL O1: 20   O2: 20   CH: _ _   FL: 20  is displayed on DCDU. switch (6) to 1. If DCDU does not display full simulated payload module quantities, check DCDU for BIT failure messages.  If no BIT failure messages are displayed, verify that CDTs are   installed correctly and powered up. NOTE Loose, damaged or dirty contacts for the fire pins and ground spring of the dispenser assemblies can cause misfires of the expendables. 38.  Press and release FLARE DISP button (22) on pilot’s Expendable count on DCDU counts down by XX; CDTs cyclic stick grip (23) one time. count up by XX.  (NOTE:  XX represents the expendable   count as determined by the MDF loaded in the CMDS and the number of CDTs installed). If DCDU does not indicate correct  dispense count, isolate   faulty LRU; if CDT does not indicate correct count, go to Task 16-5.10. 39.  Dispense all remaining simulated payloads by O1: 0   O2: 0   CH:_ _   FL: 0  is displayed on DCDU;   repeatedly pressing FLARE DISP button (22). 30 is displayed on CDTs. If CDT does not show all expendables fired, isolate the faulty LRU; remove and replace LRU per TM 55-1520-240- 23-10. GO TO NEXT PAGE