TM  1-1520-240-10            3-3-23 (6) Check destinations in MRGS or LAT/LONG coordinates as desired. (7) Check associated destination variations as desired. Remove all incorrect variations by setting DIS- PLAY switch to WP/TGT, setting the destination number to appropriate destination, and depressing the KYBD key and  ENT  key  in  that  order.  Variations  of  at  least  two destinations must be entered for automatic variation up- date computation to be performed. For accurate naviga- tion it is advised to enter variation after each destination unless the variations are the same. (8) Select DGNS operating mode (para e. be- low). NOTE The  set  will  automatically  select  combined mode (default or primary operating mode) as this allows the system to select the best pos- sible navigation method available. (9) Set the FLY-TO DEST to the desired des- tination location. c.  Procedure for Downloading Data From Dataload- er Cartridge. (1) Set the CDU mode switch to OFF. (2) Insert the preprogrammed data loader car- tridge. (3) Set the CDU mode switch to MGRS (LAT/ LONG may be used). Enter desired GPS code (M or Y) mode of operation. (4) Set  the  DISPLAY  switch  to  WIND-UTC/ DATA. (5) To display the select menu depress the ENT key twice. 1>SEA CURRENT 2>SURFACE WIND 3>GPS STATUS 4>DATA LOAD end (6) To select the DATA LOADER page depress the 4 key. DATA LOADER ENTER DATA:N end (7) To begin the download depress the KYBD and enter Y (yes). (8) Observe the CDU display. The CDU shall display  DOWNLOAD  WAYPTS  and  WAIT  ACK.  If  a transmission error occurs the CDU display shall change to ERROR-RETRYING. (9) When the transmission is complete the CDU shall display DOWNLOAD WAYPTS COMPLETE. If this display is not obtained within one minute of beginning the download check the data programming and connection. (10)   Set the CDU mode switch to OFF, remove the data loader cartridge if desired, and then set the CDU mode switch to desired setting. d.  Self-Test (1) Set the MODE switch to LAMP TEST. Enter GPS mode “M” or “Y”. Verify the following: (a) All LCD on four-line display are illumi- nated. (b) The MAL lamp is illuminated. (2) Rotate the center lighting control. Verify the following: (a) All edge lighting is illuminated. (b) All keyboard keys are illuminated. (3) Set MODE switch to TEST. (a) While  test  is  performing,  depress  the DIM pushbutton several times, then the BRT pushbutton several times. The LCD display should glow dimmer then brighter. Adjust LCD display for comfortable viewing. (b) After Doppler and/or GPS self test have completed (approximately 15 seconds for Doppler, up to 2 minutes for GPS), one of the following displays will be observed in the left and right displays: NOTE In the event the TEST mode display is not GO ALL the system should be recycled through OFF to verify the failure is to a momentary one.