TM 55-1510-220-10 with  "N"  or  "S"  to  indicate  north  or south   hemisphere.      Example:   North 4749 km = N 4749.  Observe northing kilometers appear in left data display as keys are pressed. 6. INSERT/ADVANCE               pushbutton Press.    Observe  extra  precision  display related to present position northing and easting, to nearest meter, appears in left and right data displays, respectively. 7. INSERT/ADVANCE pushbutton Press.    Observe  extra  precision  display related  to  present    position    northing and  easting,  to  nearest  meter,  appears in left and right data displays, respectively. 8. Load  extra  precision  easting  value  by pressing keys in sequence, starting with "E".    Example:  297  m  East  =  E  297. Observe  easting  meters  appear  in  right data display as keys are pressed. 9. INSERT/ADVANCE               pushbutton Press.      Observe   INSERT/ADVANCE pushbutton annunciator remains illuminated. 10. Load  extra  precision  northing  value  by pressing keys in sequence, starting with "N"  or  "S".    Example:  901  m  North  = N    901.        Observe    Northing    meters appear  in  left  data  display  as  keys  are pressed.    The  value  is  always  added  to normal  value  regardless  of  which  key (N/S)    is    pressed    to    initiate    entry. Normal entry establishes the hemisphere. NOTE The  "W"  key  may  be  used  to  initiate easting entries; however, the computer  will  always  interpret  such entries as an "E" input. NOTE The extra precision values are always added to normal values. NOTE Any data inserted when HOLD pushbutton annunciator is not illuminated will be rejected by computer. 11. INSERT/ADVANCE               pushbutton Press.      Observe   INSERT/ADVANCE and   HOLD   pushbutton   annunciators' remain   illuminated.      North   position error     and     east     position     error     in kilometers will appear in left and right data displays, respectively. 12. If   WARN      annunciator   illuminates, proceed  to  step  13.    otherwise  proceed to     step     8     in     procedure:     "Normal Geographic      Present      Position  Check and Update." 13. Data   selector   DSRTK/STS.      Observe action  code  "02"  and  malfunction  code "49".        This    indicates    radial    error between     loaded     position     and     INS position exceeds 62 kilometers. Operator   must evaluate possibility that INS    is    in    error    or    reference    point position  is  incorrect.    It  is  possible  to force INS to accept updated position by setting  data  selector  to  UTM  POS  and proceeding    to    step    9    of    procedure: "Normal   Geographic   Present   Position Check and Update." 14. If   updating   is   to   be   rejected   Press HOLD   pushbutton.      Observe   HOLD and    INSERT/ADVANCE    pushbutton annunciators extinguish. INS returns to normal operation. Change 2       3-69