TM 55-1520-240-T CHAPTER 12 UTILITY SYSTEM TROUBLESHOOTING CHAPTER OVERVIEW Chapter  12  contains  procedures  for  Utility  System  troubleshooting.  Each  system  and  failure  symptom  is  listed  below.  Included  in  this chapter  are  locations  and  views  of  all  electrical  connectors,  receptacles,  relays,  and  ground  connections  for  the  Utility  System Refer to TM 55-1520-240-23 for required maintenance procedures. SYSTEM PARA WINDSHIELD  ANTI-ICING 12-1 FIRE DETECTION 12-2 FAILURE SYMPTOM SYSTEM PARA FIRE  EXTINGUISHING 12-3 WINDSHIELD WIPERS 12-4 LIST WINDSHIELD ANTI-ICING SYMPTOM TASK SYMPTOM TASK CTR WSHLD ANTI-ICE CONT CIRCUIT BREAKER WILL  NOT  STAY  CLOSED CTR WSHLD ANTI-ICE HEAT CIRCUIT BREAKER WILL  NOT  STAY  CLOSED CENTER WINDSHIELD CONTINUES TO HEAT WHEN CTR WINDSHIELD SWITCH IS AT OFF CENTER WINDSHIELD DOES NOT GET WARM FIRE DET CIRCUIT BREAKER WILL NOT STAY CLOSED NO.  1  ENGINE  AND  NO.  2  ENGINE  FIRE  HANDLE  FIRE PULL/FUEL SHUTOFF CAPTIONS DO NOT LIGHT DURING  TEST SYMPTOM TASK COPLT WSHLD CONT CIRCUIT BREAKER WILL NOT 12-1.3 STAY  CLOSED COPILOT’S  WINDSHIELD  CONTINUES  TO  HEAT 12-1.3 WHEN  CPLT  WINDSHIELD  ANTI-ICE  SWITCH  IS  AT OFF 12-1.3 COPILOT’S  WINDSHIELD  DOES  NOT  GET  WARM 12-1.3 COPLT WSHLD HEAT CIRCUIT BREAKER WILL NOT STAY  CLOSED FIRE DETECTION NO. 1 ENGINE FIRE HANDLE FIRE PULL/FUEL SHUT- 12-2.4 OFF CAPTION DOES NOT LIGHT DURING TEST NO. 1 ENGINE FIRE HANDLE FIRE PULL/FUEL SHUT- OFF CAPTION LIT 12-2.4 12-1.3 12-1.3 12-1.3 12-1.3 12-2.4 12-2.4 PILOT WSHLD ANTI-ICE CONT CIRCUIT BREAKER WILL NOT STAY CLOSED 12-1.3 PILOT WSHLD ANTI-ICE HEAT CIRCUIT BREAKER WILL NOT STAY CLOSED 12-1.3 PILOT’S  WINDSHIELD  CONTINUES  TO  HEAT  WHEN PLT  WINDSHIELD  SWITCH  IS  AT  OFF 12-1.3 PILOT’S  WINDSHIELD  DOES  NOT  GET  WARM 12-1.3 NO. 2 ENGINE FIRE HANDLE FIRE PULL/FUEL SHUT- OFF CAPTION DOES NOT LIGHT DURING TEST 12-2.4 NO.  2  ENGINE  FIRE  HANDLE  FIRE  PULL/FUEL  SHUT- OFF CAPTION LIT 12-2.4 Change 3 12-2.1