TM 55-1520-240-T CHAPTER 8 INSTRUMENT SYSTEM TROUBLESHOOTING CHAPTER OVERVIEW Chapter  8  contains  procedures  for  Instrument  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 Instrument System. Refer to TM 55-1520-240-23 for required maintenance procedures. SYSTEM PARA PITOT STATIC SYSTEM 8-1 GAS PRODUCER TACHOMETER SYSTEM 8-2 ENGINE OIL PRESSURE INDICATING SYSTEM 8-3 ENGINE OIL TEMPERATURE INDICATING SYSTEM 8-4 PTIT SYSTEM 8-5 TORQUE INDICATING SYSTEM 8-6 HYDRAULIC PRESSURE INDICATING SYSTEM 8-7 HYDRAULIC OIL TEMPERATURE INDICATING SYS- TEM 8-8 SYSTEM PARA TRANSMISSION OIL PRESSURE INDICATING AND WARNING SYSTEM 8-9 TRANSMISSION OIL TEMPERATURE INDICATING AND WARNING SYSTEM 8-10 FUEL QUANTITY INDICATING SYSTEM 8-11 CRUISE GUIDE INDICATING SYSTEM 8-12 TURN AND SLIP INDICATORS 8-13 MAINTENANCE PANEL POWER DISTRIBUTION 8-14 ROTOR TACHOMETER 8-15 ENGINE FUEL FLOW INDICATING SYSTEM 8-16 FAILURE SYMPTOM LIST PITOT STATIC SYSTEM SYMPTOM TASK AIMS ALT CIRCUIT BREAKER WILL NOT STAY CLOSED 8-1.4 NO HEAT FELT ON LEFT OR RIGHT PITOT TUBE, PITOT SWITCH AT ON 8-1.4 NO HEAT FELT ON LOWER RIGHT OR LOWER LEFT SIDESLIP PORTS 8-1.4 NO. 1 GAS PRODUCER TACHOMETER READS 0 PER- CENT RPM WHEN NO. 1 ENGINE IS MOTORED 8-2.3 NO. 2 GAS PRODUCER TACHOMETER READS 0 PER- CENT RPM WHEN NO. 2 ENGINE IS MOTORED 8-2.3 SYMPTOM TASK NO HEAT FELT ON UPPER RIGHT OR UPPER LEFT SIDESLIP PORTS 8-1.4 NO. 1 OR NO. 2 PITOT SYSTEM LEAKS 8-1.4 NO. 1 OR NO. 2 SIDESLIP SYSTEM LEAKS 8-1.4 PILOT OR COPILOT ALTIMETER VIBRATOR DOES NOT OPERATE 8-1.4 GAS PRODUCER TACHOMETER SYSTEM NO. 1 ENGINE GAS PRODUCER TACHOMETER READING FLUCTUATES OR IS ERRATIC 8-2.3 NO. 2 ENGINE GAS PRODUCER TACHOMETER READING FLUCTUATES OR IS ERRATIC 8-2.3 SYMPTOM TASK PITOT HEAT CIRCUIT BREAKER WILL NOT STAY CLOSED 8-1.4 PITOT STATIC SYSTEM LEAKS 8-1.4 YAW PORT HEAT CIRCUIT BREAKER WILL NOT STAY CLOSED 8-1.4 GO TO NEXT PAGE Change 7  8-2.1