TM 1-1510-218-10 2-121 Table 2-12.  C-12 Caution/Advisory Annunciator Panels  (Continued) NOMENCLATURE COLOR CAUSE FOR ILLUMINATION AIRCRAFT EFFECTIVITY #1 NAC LOW Yellow #1  engine  has  20  minutes   C  or  30  minutes    D  T1  fuel remaining at sea level, normal cruise power consumption rate. All CABIN DOOR Yellow Cabin/cargo door open or not secure. All REV NOT READY Yellow Propeller   levers   are   not   in   the   high   RPM   (low   pitch position) with the landing gear extended. All #2 NAC LOW Yellow #2  engine  has  20  minutes   C  or  30  minutes    D  T1  fuel remaining at sea level, normal cruise power consumption rate. All #2 EXTGH DISCH Yellow #2 engine fire extinguisher discharged. All #1 VANE FAIL Yellow #1   engine   ice   vane   malfunction.      Ice   vane   has   not attained proper position. All DUCT OVERTEMP Yellow Excessive  bleed  air  temperature  in  environmental  heat ducts. All IFF Yellow Transponder fails to reply to a valid mode 4 interrogation. All BATTERY CHARGE Yellow Excessive charge rate on battery. All PROP SYNC ON Yellow Synchrophaser turned on with landing gear extended. C  D #2 VANE FAIL Yellow #2   engine   ice   vane   malfunction.      Ice   vane   has   not attained proper position. All HYD FLUID LOW Yellow Hydraulic fluid level in reservoir is low. D2  T1 PASS OXY ON Green Passenger oxygen system is on. D #1 VANE EXT Green #1 ice vane extended. All #1 IGN ON Green #1   engine   ignition/start   switch   on   or   #1   engine   auto ignition switch armed and engine torque below 20%. All L BL AIR OFF Green Left environmental bleed air valve closed. All R BL AIR OFF Green Right environmental bleed air valve closed. All #2 IGN ON Green #2   engine   ignition/start   switch   on   or   #2   engine   auto ignition switch armed and engine torque below 20%. All #2 VANE EXT Green #2 ice vane extended. All #1 AUTO- FEATHER Green #1 engine autofeather armed with power levels advanced above 90% N₁. C  D AIR COND N₁ LOW Green #2 engine RPM too low for air conditioning load. All EXTERNAL POWER Green External power connector plugged in. All FUEL CROSS- FEED Green Cross-feed valve open. All BRAKE DEICE ON Green Brake deice system activated. All #2 AUTO- FEATHER Green #2 engine autofeather armed with power levers advanced above 90% N₁. C D