TM 10-3930-675-10 0020 00-23 ERROR CODES - CONTINUED 0020 00 Table 4. Error Codes - Continued. ERROR CODE DISPLAY LAYOUT DRIVER ACTION ERROR CODE EXPLANATION VEHICLE LIMITATIONS 450 Stop Vehicle Press RESET. Finish mission. Notify maintenance. Warning - Degraded Operation Ambient temperature too high Temperature sensor defective. ECU 792 defective. None. 451 Stop Vehicle Press RESET. Finish mission. Notify maintenance. Warning - Degraded Operation Supply voltage too high Alternator defective. Stop vehicle by switching to neutral. 452 Stop Vehicle Press RESET. Finish mission. Notify maintenance. Warning - Degraded Operation Supply voltage too low Power supply off. Alternator defective. Stop vehicle by switching to neutral. 618 Stop Vehicle Press RESET. If error shows again, notify maintenance. Finish mission. Warning - Degraded Operation Logical error at direction select signal     -     transmission     ECU detected a wrong signal combi- nation for the direction Cables defective. Shift lever defective. Stop vehicle by switching to neutral. 622 Press RESET If error shows again, notify maintenance. Finish mission. Information/Maintenance Logical  error  at  axle  connec- tion - feedback axle connection measured by transmission ECU  and  output  signal  action connection do not match Cables defective. Switch defective. Mechanical error. When shifting from 2WD to 4WD or vice versa, engage forward drive and immediately return to neutral. Turn the ignition switch off for at least 30 seconds, then turn switch back on. 637 Finish Mission Notify maintenance. Information/Maintenance Short circuit to battery voltage or open circuit at transmission sump temperature sensor input - voltage too high Cables defective. Sensor defective. Connector pin broken. None