STEERING CONTROL DEVICE, VEHICLE POWER SOURCE SYSTEM, AND VEHICLE

The present invention relates to a steering control device (50) including a controller configured to control driving of a motor (41) that generates a torque. The torque is a torque applied to a steering mechanism (12, 14) of a vehicle using electric power from at least any one of an in-vehicle main power source (71) and an auxiliary power source (70A) that backs up the main power source (71). The controller is configured to wait (S302) for the auxiliary power source (70A) to be charged to an extent that the main power source (71) is able to be backed up and to permit (S103) the vehicle to travel when the controller is activated with an activation operation for the vehicle as a trigger and transitions to a state where control of the motor is executable. The invention further relates to a corresponding power source system and vehicle.