Shift range control apparatus

A shift range control system for controlling a shift range switching system that switches shift ranges by controlling driving of a motor, the shift range control system comprising:

• a processor;
• a non-transitory computer-readable storage medium;
• and
• a set of computer-executable instructions stored on the non-transitory computer-readable storage medium that, when read and executed by the processor, cause the processor to implement:
• acquiring a motor rotation angle signal that is based on a rotation position of the motor from a motor rotation angle sensor that detects a rotation of the motor, and calculates a motor angle based on the motor rotation angle signal;
• acquiring an output shaft signal that is based on a rotation position of an output shaft from an output shaft sensor that detects the rotation position of the output shaft to which the rotation of the motor is transmitted;
• setting a target rotation angle based on a target shift range and the output shaft signal;
• controlling driving of the motor such that the motor angle becomes the target rotation angle;
• and
• setting the target rotation angle to a target limit value, in response to the target rotation angle that is set based on the output shaft signal being a value at which rotation occurs that is further toward a back side in a rotation direction than the target limit value that is set based on shift ranges before and after switching.

A shift range control method for controlling a shift range switching system that switches shift ranges by controlling driving of a motor, the shift range control method comprising:

• acquiring a motor rotation angle signal that is based on a rotation position of the motor from a motor rotation angle sensor that detects a rotation of the motor, and calculates a motor angle based on the motor rotation angle signal;
• acquiring an output shaft signal that is based on a rotation position of an output shaft from an output shaft sensor that detects the rotation position of the output shaft to which the rotation of the motor is transmitted;
• setting a target rotation angle based on a target shift range and the output shaft signal;
• controlling driving of the motor such that the motor angle becomes the target rotation angle;
• and
• setting the target rotation angle to a target limit value, in response to the target rotation angle that is set based on the output shaft signal being a value at which rotation occurs that is further toward a back side in a rotation direction than the target limit value that is set based on shift ranges before and after switching.