On Monday Jenne made the AWG_LINES guardian nominal state IDLE because the guardian was put into ERROR when the INJECTING state was requested and could not function correctly.
The error was something to do with awg being unable to connect to excitation channels.  None of the excitation channels were able to be connected to.  Jenne's AWG_LINES error log attached.

I tested this guardian again tonight since we needed the lines for an ITMX ring heater temperature increase (from 0.5 to 0.8 on the filter input).  
AWG_LINES seems to work as expected again, so I switched the nominal AWG_LINES state back to INJECTING and changed ISC_LOCK such that NOMINAL_LOW_NOISE puts AWG_LINES into INJECTING.