TM 1-1510-224-10 NOTE On  test  set,  TS  PWR  ON  annunciator (clear) illuminates and remains illuminated throughout the test sequence  until  aircraft  power  to  test set    (via    test    set    power    cable)    is disconnected or shut off. 4. Perform the following operations on the M- 91 test set: a. Press   to   test   all   four   annunciators on  test  set.    Each  annunciator  will illuminate. NOTE Replace   any   annunciator   that   does not illuminate when pressed.  If none of the indicating annunciators illuminate,   return   test   set   to   AVUM (aviation unit maintenance). b. Rotate   TEST    SEQUENCE    switch clockwise   to   TS   RESET   position. No visual indication will occur. c. Rotate   TEST    SEQUENCE    switch clockwise to SV SELF TEST position. STRAY VOLTAGE annunciator (red) will illuminate. d. Rotate   TEST    SEQUENCE    switch clockwise     to     next     position, TS RESET. STRAY VOLTAGE annunciator (red) will extinguish. e. Rotate   TEST    SEQUENCE    switch clockwise  to  next  position,    STRAY VOLT. STRAY VOLTAGE annunciator (red) should not illuminate. f. Rotate   TEST    SEQUENCE    switch clockwise    to    next    position,    SYS NOT   RESET.      SYS   NOT   RESET annunciator (amber) should not illuminate. If annunciator illuminates, press and release MANUAL   SYSTEM   RESET   switch and  SYS  NOT  RESET  annunciator should then extinguish. NOTE When  the  MANUAL  SYSTEM  RESET switch  is  pressed  and  released,  and 28  volts  DC  power  is  being  applied, the     sequencer     switch     inside     the dispenser   assembly   resets,   making an audible sound as it rotates.  If the sequencer switch has been previously  reset  or  if  the  switch  is  in position   12   or   24,   there   will   be   no such sound. g. Rotate   TEST    SEQUENCE    switch clockwise    to    next    position,    DISP COMPL. h. Press   pilot's   CHAFF    DISPENSER switch once.  Press copilot's  CHAFF DISPENSER switch once.  On MFD, for each depression, CHAFF counter   should   count   down   by   an increment of one. i. On   MFD,   depress   L3   line   selector switch until PRGM appears. j. Depress pilot's  CHAFF DISP  switch once.    On  MFD,  number  shown  on CHAFF  counter  should  decrease  by one. k. On  MFD,  depress  line  select  switch L4 to set CHAFF to PRGM. l. Depress     copilot's CHAFF DISP switch    once.        On    MFD,    CHAFF counter  will  read  29  minus   SALVO COUNT multiplied by BURST COUNT as displayed on  ASE  setup page. m. Repeatedly depress a  CHAFF DISP switch  until   CHAFF   counter   reads 00  and  LL    CHAFF   EXPENDED   is displayed on MFD.  The  DISPENSE COMPLETE   lamp   (green)   on   test set shall be illuminated. NOTE The DISPENSER COMP lamp may fail to illuminate during the previous step due  to  improper  connection  between the   base   plate   and   breechplate.      If this   happens,   remove   and   reinstall base plate to ensure proper connection and repeat CHAFF DISPENSE tests.  If this still does not result  in  proper  operation,  verify  the C-F    selector    switch    is    in    the    C position. 5. Perform the following operations on the M- 91 test set: a. Rotate   TEST    SEQUENCE    switch counterclockwise to SYS NOT RESET  position.    SYS NOT RESET annunciator (amber) will illuminate. b. Press and release MANUAL SYSTEM RESET switch.   SYS NOT RESET     annunciator     (amber)     will extinguish and DISPENSE COMPLETE    lamp:          will     remain illuminated. c. Reset   the   CHAFF   counter   to   30. ALL  CHAFF  EXPENDED  shall  not be    displayed    on    MFD.        Do    not depress 4-8