TM 1-1510-223-10 Table 3-13. Lightning Sensor System Failure Codes LX FAIL CODE HARDWARE/FIRMWARE (mn) FAILURE 00 No LX system failure (not displayed) 01 Power supply out-of-tolerance 02 Invalid configuration 03 Reserved 04 Data Processor RAM failure 05 Data Processor Checksum failure 06 Data Processor shared RAM failure 07 Reserved 08 Reserved 09 I/O Processor RAM failure 0A I/O Processor Checksum failure 0B I/O Processor shared RAM failure 0C H_N out-of-range 0D H_W out-of-range 0E Reserved 0F H_NLF out-of-range 10 H_WLF out-of-range 11 E_LF out-of-range 12 No data from antenna BT03847 (9) IDENT - MIC - OUT.  Selects source of air-craft identification signal. (a) IDENT.  Activates transmission of identification pulse (IP). (b) MIC.     Enables     either     control wheel   POSIDENT   switch   to   activate   transmission   of ident signal from transponder. (c) OUT.  Disallows outgoing signal. (10)    MODE 4 reply annunciator light. Illuminates to indicate a reply has been made to a valid Mode 4 interrogation. (11)    MODE 4 AUDIO OUT switch.   Selects monitor mode for mode 4 operation. (a) AUDIO.  Enables sound and sight monitoring of mode 4 operation. (b) LIGHT. Enables monitoring REPLY indicator for mode 4 operation. (c) OUT.  Deactivates monitor mode. (12)    MODE    3/A    code    selectors.       Select desired reply codes for mode 3/A operation. (13)    MODE     2     code     selectors.         Select desired  reply  codes  for  mode  2  operation.    The  cover over   mode   select   switches   must   be   slid   forward   to display the selected mode 2 code. (14)    MODE     1     code     selectors.         Select desired reply codes for mode 1 operation. (15)    MODE 4 TEST-ON-OUT switch. Selects test mode of Mode 4 operation. (a) TEST.     Activates   built-in-test   of mode 4 operation. (b) ON.  Activates mode 4 operation. (c) OUT. Disables mode 4 operation. (16)    MODE  4  code  control.   Selects  preset mode 4 code. 3-86