TM 10-3930-675-10 0020 00-25 ERROR CODES - CONTINUED 0020 00 Table 4. Error Codes - Continued. ERROR CODE DISPLAY LAYOUT DRIVER ACTION ERROR CODE EXPLANATION VEHICLE LIMITATIONS 651 Finish Mission Notify maintenance. Information/Maintenance Logical  error  at  engine  speed input - transmission ECU mea- sures    engine    speed    over    a threshold and the next moment the measured speed is zero Cables defective. Sensor defective. Wrong size sensor gap. Gearshift quality is reduced due to another control mode. (Operating mode: substitute clutch control) 652 Press RESET Finish mission. Notify maintenance. Warning - Degraded Operation Short circuit to battery voltage or open circuit at turbine speed input - transmission ECU mea- sures   a   voltage   higher   than 7.0V at speed input pin Cables defective. Sensor defective. Wrong size sensor gap. Gearshift quality is reduced due to another control mode. (Operating mode: substitute clutch control) If there is also a failure at output speed, transmission ECU shifts to neutral. Limp home. 653 Press RESET Finish mission. Notify maintenance. Warning - Degraded Operation Short  circuit  to  ground  at  tur- bine speed input - transmission ECU  measures  a  voltage  less than 0.45V at speed input pin Cables defective. Sensor defective. Gearshift quality is reduced due to another control mode. (Operating mode: substitute clutch control) If there is also a failure at output speed, transmission ECU shifts to neutral. Limp home. 654 Press RESET Finish mission. Notify maintenance. Warning - Degraded Operation Logical  error  at  turbine  speed input - transmission ECU mea- sures   turbine   speed   over   a threshold    and    at    the    next moment the measured speed is zero Cables defective. Sensor defective. Wrong size sensor gap. Gearshift quality is reduced due to another control mode. (Operating mode: substitute clutch control) If there is also a failure at output speed, transmission ECU shifts to neutral. Limp home.