Transmission ratio controller and method for determining transmission ratio abnormality

A transmission ratio controller including circuitry, the circuitry comprising:

• a transmission ratio calculator configured to calculate a request transmission ratio to a transmission mechanism in accordance with a state of an internal combustion engine;
• a transmission ratio instructor configured to transmit a control signal to an actuation mechanism based on the request transmission ratio, the actuation mechanism being configured to actuate the transmission mechanism;
• and
• an abnormality determiner configured to determine whether a transmission ratio of the transmission mechanism is abnormal, wherein
• at least two of the request transmission ratio, an instruction transmission ratio that is a transmission ratio corresponding to the control signal, or an actual transmission ratio that is a transmission ratio achieved by the transmission mechanism are transmission ratios subject to comparison, and
• the abnormality determiner is configured to determine that when a difference obtained by comparing the transmission ratios subject to comparison is greater than or equal to a predetermined specified value, the transmission ratio of the transmission mechanism is abnormal.