A method is provided for augmenting GPS data using an in-vehicle vision-based module. A vehicle position is determined utilizing position-related data obtained from a position module. A position error is estimated on a periodic basis. A determination is made whether the position error estimate exceeds a first predetermined error threshold. Tracking data is generated for the vehicle over a course of travel utilizing captured images from the in-vehicle vision based module. The tracking data is integrated with the position-related data to estimate the vehicle position in response to the position error estimate exceeding the first predetermined error threshold. A determination is made whether the position error estimate decreases below a second predetermined error threshold. The vehicle position is re-determined using only the position-related data when the position error estimate decreases below the second predetermined error threshold.