Automatic transmission control system and control method

An automatic transmission control system, comprising:

• a shift control device that controls shifting of an automatic transmission installed on a vehicle, in one of an automatic shift mode in which shifting of the automatic transmission is carried out based on a shift diagram, and a manual shift mode in which shifting of the automatic transmission is manually carried out;
• a shift command detecting device that detects at least one shift command of an upshift command for shifting up the automatic transmission and a downshift command for shifting down the automatic transmission, said shift command being manually entered;
• and
• a command time measuring device that measures a shift command time for which the shift command is detected by the shift command detecting device, wherein
• when the shift control device controls shifting of the automatic transmission in the automatic shift mode, the shift control device switches from the automatic shift mode to a shift inhibition mode in which shifting of the automatic transmission is inhibited, without switching to the manual shift mode, when the shift command time measured by the command time measuring device exceeds a specified time, and
• when the shift command time is equal to or less than the specified time, the shift control device switches from the automatic shift mode to the manual shift mode.