TM 55-1510-220-10 Table 2-7.  Caution/Advisory Annunciator Panel Legend (sheet 2 of 2) CAUTION/ADVISORY ANNUNCIATOR NOMENCLATURE COLOR CAUSE FOR ILLUMINATION A/C COLD OPN Green Air conditioner is operating in cold mode, or ambient temperatures require switching to cold mode if air conditioner operation is to be continued. No. 1 DVANE EXT Green No. 1 ice vane extended FUEL CROSS-FEED Green Crossfeed valve open AIR COND N1 LOW Green No. 2 engine RPM too low for air conditioning load No. 2 VANE EXT Green No. 2 ice vane extended No. 1 IGN ON Green No. 1 engine ignition/start switch on No. 1 engine autoignition switch armed and engine torque below 20 percent L BL AIR OFF Green Left environmental bleed air valve closed EXTERNAL POWER Green External power connector plugged in R BL AIR OFF Green Right environmental bleed air valve closed No. 2 IGN ON Green No. 2 engine ignition/start switch on No. 2 engine autoignition switch armed and engine torque below 20 percent No. 1 AUTOFEATHER Green No.  1  engine  autofeather  armed  with  power  levers  advanced  above90% N₁ No. 2 AUTOFEATHER Green No.  2  engine  autofeather  armed  with  power  levers  advanced  above90% N₁ BRAKE DEICE ON Green Brake deice system activated lights   are   tested   by   activating   the   ANNUNCIATOR   TEST switch, located on the right subpanel near the caution/advisory panel.      The   system   is   protected   by   two   5-ampere   circuit breakers placarded ANN PWR and ANN IND on the overhead circuit  breaker  panel  (fig.    2-27).    The  annunciator  system lights are dimmed when the MASTER PANEL LIGHTS switch is  ON  and  the  pilot's  flight  instrument  lights  are  illuminated. The lights are automatically reset to maximum brightness if: (1) The  main  aircraft  power  (both  DC  generators) are OFF. (2) The    INST    INDIRECT    LIGHTS    switch    is rotated clockwise. (3) The MASTER PANEL LIGHTS switch is off. (4) The  MASTER  PANEL  LIGHTS  switch  is  ON and the PILOT INST LIGHTS switch if OFF. (5) Master warning annunciator (red). A MASTER  WARNING  annunciator  is  provided  for  both  the pilot   and   the   copilot   and   is   located   on   each   side   of   the glareshield   (fig.   2-30).      Any   time   a   warning   annunciator illuminates,  the  MASTER  WARNING  light  will  illuminate, and   will   stay   illuminated   until      the   MASTER   WARNING annunciator  is  pressed  to  reset  the  circuit.    If  a  new  condition occurs,  the  annunciator  will  be  reactivated,  and  the  applicable annunciator panel annunciator will illuminate. (6) Master    caution    annunciator    (yellow).        A MASTER CAUTION LIGHT is provided for both the pilot and copilot     located     adjacent     to     the     MASTER     WARNING annunciator.  Whenever a Change 2   2-78