CONTROL DEVICE FOR AUTOMATIC TRANSMISSION

PROBLEM TO BE SOLVED: To secure a range where an engine brake works without a sense of incongruity by judging a travel state at the time of judging a plurality of ranges, and giving priority to judgment of a low speed side range in the case of the travel state satisfying a present condition. SOLUTION: In the case of judging the output state of a shift position switch 19 to indicate a third range and an L-range, it means that one range is outputted by a failure, and in case of detecting two range signals for the first time, it is judged negatively. Whether or not a present set speed stage is the third gear speed is then judged. In the affirmative case, whether or not the vehicle speed is the set speed or higher is judged. In the case of the vehicle speed being the set speed or higher, the third range is set, and the third gear speed is maintained so as to prevent shock caused by engine braking force generated in association with down-shift. In the case of the vehicle speed being less than the set speed, the L-range is set, and a flag is set to 1. The low speed side range is given priority shock since is small even with the generation of down- shift if the vehicle speed is low.