| 摘要 |
A shift control method for an automatic transmission while a vehicle runs up a slope while towing a trailer includes the steps of determining if present shift lever position indicates a driving range 2, calculating weight-slope resistance if the shift lever position indicates the driving range 2, determining if the weight-slope resistance is greater than a threshold weight-slope resistance, measuring time duration during which the weight-slope resistance is maintained over the threshold value if the weight-slope resistance is greater than the threshold weight-slope resistance, determining if the time duration is longer than a threshold time, converting a present normal shift pattern into a trailer-towing shift pattern if the time duration is longer than a threshold time, and returning the trailer-towing shift pattern to the normal shift pattern if the weight-slope resistance becomes equal to or less than the threshold weight-slope resistance and this condition is maintained over a second threshold time. |
