A rod-lock mechanism is provided in an automatic transmission for a vehicle. The rod-lock mechanism has an engaging pin which will be engaged with a rod when the rod is in its initial position, so as to hold the rod in its initial position. The rod-lock mechanism further has an electric actuator for driving the engaging pin when electric power is supplied, so that the engaging pin is brought out of engagement from the rod. A forced parking current supply unit controls electric power supply to the electric actuator. When the electric power is supplied to the electric actuator, the rod is moved in a direction of a parking position to bring a vehicle into a parking condition.