I just figured what PO773 code is. It is the Torque converter lock up solenoid. The solenoid has 2 bolts that can be undone from the top of the car. The solenoid is located behind park neutral safety switch. The plug has a pink with black strip. This is A140E transmission. The problem with the vehicle was the Check engine was on and the RPM would not drop 300 RPM on the freeway at cruising speed. I only post this answer because the only thing I could find in the web was the lock up solenoid was on the valve body. Toyota calls this solenoid #3.