ARMY TM 9-6115-672-14 AIR FORCE TO 35C2-3-444-32 MARINE CORPS TM 09244A/09245A-14 4-31 Yes   CIM DISPLAY SCREEN FREQ GAGE FLUCTUATES CIM display screen FREQ gage fluctuates. Check FAULT INDICATOR on CIM display screen.  Is a fault displayed? (4, Figure 2-9) Go to troubleshooting section corresponding to fault displayed.  See Symptom Index, page 4-10. Is Engine speed fluctuating? No Is HEARTBEAT LED on I/O interface module blinking? Check speed control unit LED indicators.   Are the SPEED SENSOR, ACTUATOR, and DC POWER LEDs fluctuating? No Yes Yes Continued on next page No Check Speed control unit.  Is DC POWER LED lit and steady, and ACTUATOR and SPEED SENSOR LEDs fluctuating? Yes Yes Replace speed control unit. No Continued on next page Replace I/O interface module  (see para. 4.8.25). Replace CIM.  (see para. 4.8.16). No Notify next higher level of maintenance. Not OK