an apparatus for controlling an automatic transmission of a vehicle in the absence of a driving mode signal indicating a driving mode of the vehicle , includes monitoring means for monitoring output from a driving mode sensor ; determining means for determining whether a driving mode signal has been received from the driving mode sensor based on the monitoring ; sensing means for sensing a direction in which the vehicle is traveling ; transmission control means placing the automatic transmission in first gear when the determining means determines that a driving mode signal has not been received , and for controlling the automatic transmission such that the vehicle continues to travel in the detected direction .