A system for determining an error in a sensed position of a machine includes a position sensing system, a dead reckoning system, and a controller. The controller is configured to determine a difference between a sensed position and a calculated position determined by dead reckoning. The difference is compared to an error threshold defining a maximum acceptable distance between the sensed position of the machine and the calculated position of the machine and an error signal generated if the difference exceeds the error threshold. A pair of offset dead reckoning processes may be used.